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エロ Chapter 6

エロ The Big C and a Little UV

Sunlight is a killer! This is the clear message from the medical profession at present. The warm, sensual feeling that you get from lying in the sun is probably immoral, and you ought to be at home taking antibiotics. Yet we persist in taking holidays in the sun, and nipping out of doors at lunchtime. Can it be that we know something the doctors don't? It definitely can, and some of the evidence to prove us right has been around for half a century. Put aside for a moment the question of skin cancer - which is dealt with in the next chapter - and think about cancers in general, which kill far more people every year.

Twenty-five years ago Dr John Ott investigated the background to a report that children at a school in Illinois had five times the national rate of leukemia.[1] He found that the schoolhouse was a plain, modern building with very large windows in every room, and all the pupils who developed leukemia had been in two particular classrooms. In these two rooms the teachers always kept the large curtains completely drawn across the windows to reduce glare and distraction, and to keep the children's attention on schoolwork. The indoor lighting was therefore on all the time, and this was 'warm white' fluorescent. The whole class spent its working day in light of twilight intensity, with no blue or UV light at all except at playtime - and in Illinois they have some hard winters, during which the children might not go out to play at all.

Several years later the two teachers in question left the school, and their replacements kept the classroom curtains open all the time. The lights were also replaced with cool white fluorescent ones, and of course needed to be used less. From then on there was not a single case of leukemia in the school for as long as Dr Ott followed it up. No other explanation has been put forward for this remarkable mini-epidemic of leukemia; although in isolation it proves nothing, it started Dr Ott thinking about the possibility of a link between sunlight and cancer.

In fact this had been commented on half a century ago. In 1936, a report in The Lancet by Peller, a US Navy doctor, suggested an inverse relationship between skin cancer and all other cancers. He observed that Navy personnel had eight times the skin cancer rate of the rest of the population, but only forty per cent of the total death rate from cancer.[2] He proposed that the obvious explanation for this was the greater amount of sunlight to which men serving in the Navy were exposed. Nowadays, many naval personnel probably spend their whole working lives at computer consoles, but in 1936 they naturally led an outdoor life and were in the sun a great deal.

Peller made the startling suggestion that by using high intensities of light, either sunlight or ultraviolet from a carbon arc lamp, we should actively induce skin cancers in patients, in order to protect them from other cancers. As cancers go, those skin cancers that have been clearly shown to be related to sunlight have obvious advantages; the most important of these is that they are visible at a much earlier stage, and can therefore be dealt with. The success rate of surgery has always been good, and if you had to choose which cancer to get, skin cancer would be an excellent choice.

In fact, skin cancers cause only nine per cent of the deaths from cancer every year, and organ or internal cancers ninety one per cent. What's more, the survival rate from skin cancer is very good - about ninety five per cent of sufferers live for five years or more after diagnosis, whereas only thirty six per cent of cancer victims in general live that long. The exception, of course, is the relatively rare skin cancer called malignant melanoma, which is discussed in the next chapter.

エロ The global view

The really strong sunlight effect starts to show through when you examine the relationship between sunlight exposure and cancer incidence on a global scale - the epidemiology. This has been looked at in some detail on several occasions. The simplest and clearest study is that performed by Hoffman for the Prudential Life Assurance Company in 1924.[3] He analyzed the frequency of cancers of all types in a total of 130 cities around the world (looking at almost 300,000 cancer deaths) and matched this against their latitude. The results are clearly shown in the graph above. The further the city from the equator, the greater the number of cancers. The ratio of highest frequency to lowest is around 2.5:1, which looks as though it may turn out to be a magic figure of some sort.

This study concentrated on people living in cities, so that factors such as lifestyle and levels of development should not interfere. But in 1940, when Dr Frank Apperley looked at the total mortality from cancers across the United States in both rural and urban areas, the picture he found was just the same, and very clear. He measured two factors that are likely to match closely with the average exposure of individuals to sunlight: the percentage of the population involved in agriculture (and so out of doors most of the time), and the amount of solar radiation recorded by the local Met station. He plotted these measures against the number of cancers.

This was then refined further by looking only at people over forty five (the age group in which the large majority of cancers occur), and only at the white population, who have an incidence of cancer several times higher than that of black people. Neither of these restrictions altered the results at all; the effect was the same for both methods of analysis. As you can see from the graph, the more time people are outdoors, and the more sunlight in the area where they live, the fewer cancers they develop. Interestingly, the highest ratio comes out once again to a little over 2:1.

So what mechanisms could explain this link between light deficiency and cancer? Well, several of them. The problem with researching this kind of thing is that there is no single clear-cut process involved to make it nice and easy for the scientist. Sunlight is so fundamental to our lives, and affects us in so many ways, that it may be impossible to demonstrate a single link. But we can pull several strands out of the knot, each of them a connection.

エロ The guts of the matter

In a large North American study, higher vitamin D levels appeared to give significant protection against cancer of the colon. The analysis made was of the amount of vitamin D in the diet, not of blood levels. The researchers found that the group with the lowest vitamin D intake were about 2.5 times more likely (there's that number again) to develop bowel cancer than those with the most vitamin D in their diet.[4] We know that much of the population in this country is vitamin D-deficient for much of the year, even more so than in America. Raising people's levels of this vitamin may protect them in some way from cancer. However, when this connection was examined in Japan, there did not appear to be the same correlation. This may be due, suggests the paper, to the fact that the Japanese, living nearer the equator, have a greater exposure to sunlight, and therefore more sunlight-derived vitamin D in their blood.[5] In these circumstances, dietary vitamin D will not be so important. The best-known reason why vitamin D is important is that it increases our uptake of calcium from the diet. We know that calcium plays an important part in cancer of the bowel, actively calming down the rapidly dividing cells. Vitamin D will enable these cells to take up more calcium, and this may begin to explain the sunlight effect. More recently, laboratory studies have found that there are receptor sites for vitamin D on cancer cells, and that it appears capable of converting human leukemia cells back into normal cells - at least in the test tube.

エロ A breach of security

It has been estimated that we each develop cancer once a week on average. This is how often a cell in our bodies is likely to go "rogue" and start dividing rampantly. But fortunately for us, when this happens the cell also undergoes a change in the proteins on its surface, and our immune system swiftly identifies it as "not-self", as a threat to our health, and eliminates it. In other words, developing a cancer - a real cancer - is a sign not of something going wrong with our genes, but of something wrong with our immune systems.

This is why people with AIDS are so vulnerable to strange malignancies such as Kaposi's Sarcoma. Their immune systems are damaged by the virus, which attacks the T-cells, a type of white cell crucial to the production of antibodies against invaders. AIDS particularly kills off the T-helper cells, which are normally in balance with T-suppressor cells. T-helpers stimulate the immune system to attack, while T-suppressors discourage it from so doing. With a disproportionately low level of T-helpers the immune system is powerless against infections, cancers and other threats to our well-being.

Yet there are people alive in America who have had AIDS for several years but are now fit and well. They have found ways to stimulate their bodies' production of T-cells when conventional drugs were powerless to help. A variety of methods appear to have benefited them - meditation, herbs, acupuncture and mega dose vitamin C among the most important.

It is now clear, from very recent studies on the skin as an immune organ, and from old studies on the effects of sunlight on the white blood cell count, that sunlight can have a dramatic effect in this area. When sunlight hits the skin, it stimulates the topmost layer of living cells, the keratinocytes. These are the cells which produce the keratin, the hard outer layer of dead skin that protects us from germs and injuries. It was always thought that they had no other function. But new evidence has proved that when they are triggered by ultraviolet light, keratinocytes produce a chemical called interleukin-1. IL-1 has a simple but potent effect: it causes white cells, and T-cells in particular, to multiply in number.

Since this is the only way that such cells can be mobilized quickly to respond to a threat, IL-1 has been the focus of considerable interest among immunologists in recent years. Despite detailed research, though, it has been clear that we are a long way from the day when we can synthesize it in a laboratory. Now there hardly seems to be any point. Why spend millions on manufacturing something which our own bodies will make for free in response to sunlight?

So in order to raise your white cell count, mobilize your immune system against attacks by infection or even by cancer, and absorb more protective calcium, all you need to do is sunbathe. This may help to explain why children get so many infections in winter, when we are all at risk from sunlight deficiency - and why influenza epidemics always seem to happen then too. But it may also be an important strand in the understanding of why sunlight protects against cancer.

エロ Free oxidizing radicals

Free oxidizing radicals are small negative ions with the ability to split molecules and damage cells. These atoms and small molecules with a negative charge on them are produced in chemical reactions, in the atmosphere, in food and in our bodies. Some of them are very short-lived, only existing for minute fractions of a second. However, they have a tendency to propagate rapidly, so that the production of one free oxidizing radical (FOR) can, within a very short space of time, lead to a large number.

Whether single or multiple, they have a powerful ability to react with biological molecules in damaging ways. They can break open the DNA in our chromosomes, although there are mechanisms to prevent their getting near it in its safe harbor in the cell nucleus. When they do come into contact with DNA they can split it open and alter the genetic information, leading to mutations.

They also split open antibodies, the molecules used by our immune systems to attack infections and clear allergens out of the system. This can lead to effects very like allergic reactions in some people. Also, they can break open collagen molecules, the structures that make up ligaments and hold our tissues together, and give skin its elasticity. This is why pollution and smoking can age your skin.

On the other hand, free oxidizing radicals are actually used by the white cells of the body to attack infecting agents. As a white cell engulfs a virus or bacterium, it pumps highly toxic FORs into the forming vacuole in order to kill the micro-organism. Thus FORs are necessary to the healthy functioning of our immune system; in other words, they are an example of something that is necessary in the right amounts, but can be toxic in overdose.

Our bodies possess a series of mechanisms for controlling FORs, mopping them up rapidly and preventing them from damaging tissues. These are known as antioxidants. The major ones are essential nutrients such as vitamins A, E, and C, the amino-acid glutathione, and certain minerals such as selenium. Some of these, such as vitamins A and E, protect by mopping up FORs themselves, so preventing them from damaging our cells. Others, such as selenium, are components of the enzymes which rapidly process and inactivate FORS. Damage produced by smoking, alcohol, radiation or even sunburn due to ultra-violet light, are all FOR effects. They are all prevented by high levels of antioxidants, in this case particularly vitamin A.

So FORs can be produced by large doses of ultraviolet light, but we can protect against this by an adequate intake of antioxidant nutrients, and by avoiding excess fat in our diet. Since we live in a light-poor environment, diet is more important in this respect than overdoses of light, with the exception of the annual jaunt to the Costa Packet. Torremolinos in summer is full of English people overdosing on sunlight, on alcohol, on greasy food, possibly on tobacco too. Along with the raffia ponies and peeling backs, they bring home a system so overloaded so rapidly that they may need the rest of the year in a dark room to recover. That we do not all develop skin cancer after our summer holidays only proves the effectiveness of the body's defenses when we are in good health.

 

Fat and weak

Some of the molecules most vulnerable to the effects of free oxidizing radicals are the oils and fats making up our cell walls, which are obtained from our diet. It is now well understood that the more oils there are in our diet the more antioxidants we need to protect them. Without these protective mechanisms, the fats may be damaged by FORs, and it is thought that their molecules may be twisted into an abnormal and highly toxic form, known as trans-fats. The greater the surplus of fats and oils over antioxidant nutrients in our bodies, the greater the probability of trans-fats being formed, and this alone may explain many cancers. Overdoses of ultraviolet light may cause this change, but only if we are short of the protective nutrients. Once again it is a matter of nutritional balance.

Despite the current powerful trend of opinion against them, it appears that saturated fats are not in themselves toxic. They do harm us, though, in two specific ways. Firstly, a high animal-fat diet may contain simply too much fat surplus, with the risk of trans-fats being formed. But polyunsaturated oils too can cause both of these damaging effects, so lashings of sunflower oil or margarine on your baked potato may be just as harmful as butter.

Secondly, saturated fats, which have no double bonds along their chain of carbon atoms, can simply replace unsaturated fats in the diet, and some unsaturated oils are necessary for health. The importance of unsaturation is that it means the presence of double bonds in the chemical structure of the oil. These double bonds can be opened up by enzymes and used, rather like a child's construction toy, to build new molecules. This enables the oils to be utilized by the body for cell walls and for the production of a range of other chemicals; in particular for a group of hormones called Prostaglandin's. Because we need a regular supply of them to process into other molecules, certain of these oils and fats are known as essential fatty acids.

Prostaglandin's control a large variety of biological functions, including inflammation in response to injury or infection, the formation of blood clots in arteries and veins, and the contraction of the uterus in childbirth. Saturated fats are useless in this respect, and are therefore only able to be stored and used as calories. We need polyunsaturated for normal functioning, but the greater our intake, the more molecules we have circulating which need to be protected against FOR damage, including that from UV light.

 

Human studies

In 19S9 Dr Ott finally had the opportunity he longed for: he was asked to participate in a study on the effects of sunlight on cancer in human patients. A physician at the Bellevue Medical Center in New York arranged for fifteen people with diagnosed cancer to organize their own sunlight therapy. Throughout the summer months, they spent as much time as possible out of doors, without any glasses or sunglasses. They also avoided artificial lights and televisions as much as possible. When the summer ended, the physician in charge attempted to evaluate the results. She found that fourteen out of the fifteen patients had shown no further spread in their cancers, and some even appeared to have improved. The fifteenth had continued wearing spectacles, and so would have blocked ultraviolet light from entering her eyes. Although there were no controls in this experiment, and it had run for only a few months, both Dr Ott and the doctor thought that it showed sufficient effect to be worthy of further, more detailed, investigation.

The medical authorities to whom he presented these results, with a proposal for further research, thought otherwise, and no more research was done on humans. But another medical friend of Dr Ott's did become interested, and set up an experiment using a strain of mice (known as C3H mice) that are very prone to developing cancerous tumors spontaneously. He reared separate litters under pink fluorescent tubes, under 'daylight' white tubes and under sunlight, The mice under the pink tubes showed cancers first, a month before those under white tubes and three months before those in daylight.

Strangely, this study was refused for publication! Much more work will have to be done before the medical community will accept any value for light in treating cancer, and there is no sign of it being done at present. Yet the results of the small study on humans were strongly positive, and any drug company would be delighted if it would show such a positive response to their product after only a few weeks. Take all of this evidence together and a pattern does emerge. It seems clear that we can modify our lifestyle in one simple way that will decrease our risk of developing cancer, and may even offer hope of help when we do develop it.

Chapter 7

The Melanoma Debate

1987 saw the most widespread campaign ever to try and persuade us that sunlight is dangerous and we should avoid it. Yet we still go on summer holidays in our millions, and we still come back feeling that it was worthwhile, and that we'll go again next year. Can it be that we are all so foolish that we ignore the medical evidence for the sake of two weeks of sensuality, or might our instincts be telling us the opposite of what the medical profession is telling us?

It is worth looking at the evidence with a fresh eye. For instance, everybody knows that sunlight causes skin cancer. But it is that simple? We know that cancers are much more common in hot, sunny areas such as Queensland, due to solar exposure - or do we? We all know that malignant melanoma is a skin cancer that is caused by sunburn - but is it?

The last two statements are both questionable. The first is half correct - squamous cell and basal cell carcinomas of the skin are more common in white-skinned people living in very sunny areas such as Queensland. This does not apply to cancers anywhere else in the body. The last statement is, at best, misreading of the evidence. Malignant melanoma is more common in people with the sort of skin that burns easily, but we are not in a position to say that the sunburn actually causes the cancer - it may even protect against it.

We have to take all this very seriously, because in the UK one quarter of all deaths are due to cancer. There are about 200,000 new cases of cancer every year, and of these about ten percent are skin cancers. This in turn breaks down to ninety eight per cent squamous and basal cell cancers, and two per cent melanomas.

But - and it's a very big but - the chances of surviving a skin cancer are excellent: ninety five per cent of patients are alive five years after diagnosis. This compares with thirty six per cent survival for cancers in general.[2] So, as we remarked in the previous chapter, if you have to get cancer, then skin cancer is definitely the wisest choice.

The one big exception is melanoma, of course. Although it is very rare - about 0.2 per cent of all cancers - it is the only skin cancer that normally metastasizes (spreads to distant parts of the body), and the death rate is much higher. The five-year survival rate is fifty per cent, much poorer than the other skin cancers. It still doesn't rank in the top ten killers, but if it were avoidable by something as simple as staying out of the sun, this would plainly be a sensible thing for us all to do.
With the common forms of skin cancer, squamous and basal cell, the relationship with sunlight is clear. They occur usually on the exposed surfaces, such as the face, scalp and the back of the hands, usually in old age, in people who have spent many years working out in the sun. They are particularly common in people who have lived for some time in the tropics. In other words, it is long-term steady exposure to sunlight, for several hours a day, over many years, that triggers off these cancers.

Because it is so much less common, it has been much harder to gather sound evidence on melanoma and its relationship to sunlight. But until recently, a single fact was always quoted as proof that it was triggered by sun. This was the particularly high incidence of melanoma in Queensland, in Northern Australia. This is one of the hottest and sunniest places on earth, and it seemed that the link was obvious and inescapable.

Yet when studies were done in Queensland itself, it was found that within the state boundaries, the sunnier the area the fewer melanoma cases occurred. The disease was more common in the coastal areas, which had less sunlight in summer, when the amount of UV was higher. This clearly bemused the doctors doing the research, as they had no other explanation for melanoma than damage from UV.[3]

The next episode in the story also occurred in Australia, with a survey in New South Wales which showed that there was a greater risk of melanoma in women who had been exposed to fluorescent light at work than in those who have not. The longer these women had been working under fluorescent lights, the greater their risk of developing the cancer. Sunlight appeared to play no significant part in causing the problem. [4]

Critics of this study said that this might be a false result due to the fact that people of a higher social class were more prone to melanoma, and also - but incidentally - were more likely to work in offices with fluorescent lighting, But a study in the New York area confirmed the finding in a group who were all predominantly middle class.

With no difference between the social class of the melanoma sufferers and the non sufferers, fluorescent lights still appeared to increase the risk. [5]

That was in 1982. In 1984 a large study of 507 melanoma cases and 507 matched controls (matched for age, sex and place of residence) was performed in Western Australia. This one found that, if anything, exposure to sunlight protected against melanoma. People who regularly spent ten hours a week or more in the sun had a lower chance of developing the disease, and the longer time they spent in the sun each week the lower their risk. There was an increase of melanoma in people who went boating or fishing twice a week, but this was more than the increase in those who sunbathed - hardly strong evidence of a sunlight link. In fact, the worse a person's history of sunburn in the past, the less the chance of their developing at least one type of the cancer, known as nodular melanoma. [6]

The final piece of research, which looks as though it may have made sense of the whole conundrum, was conducted in Canada in 1985. This showed that the real risk came not from sunburn, but from having the type of skin that burnt easily. Whether or not a person actually got sunburned was not important in comparison to their tendency to burn easily and tan poorly. Those with the most sensitive skin had twice the risk of melanoma of those who never burned. [7]

Despite all this, the Royal College of Physicians Report published in April 1987 still said that sunlight was the culprit in melanomas The conclusion was largely based on the research of one doctor in Glasgow who found a high proportion of people with a history of bad sunburn in her study. She took no account, however, of the point made by the Canadian study, that people who burn badly are likely to have sensitive skin - and of course in Scotland a very high proportion of the population has Type One, or Celtic, skin. They may never tan, only develop freckles, and the lack of melanin in their skin makes them susceptible to sunburn.

There are several small points that round out this argument. Firstly, studies in the laboratory show that vitamin D suppresses malignant melanoma - and also leukemia - in test tube experiments. [9] Understandably, no one is attempting to reproduce this in humans, but it does offer a possible explanation for the apparent protective effect of regular sunlight against melanoma.

Secondly, the ultraviolet wavelengths that produce vitamin D the skin are entirely absent from normal fluorescent light - and the total UV exposure from working under fluorescent lights for a year has been calculated to be equivalent to forty minutes of autumn sun.[10] So how can UV be the culprit?

Thirdly, the incidence of malignant melanoma is going up most rapidly in some far from tropical areas such as Scandinavia and Scotland. It has been estimated to be doubling approximately every ten to twenty years. [11] Nobody has yet shown how this increase could be due to exposure to sunlight. But it could very well be due to increasing exposure to indoor lighting.

Finally, despite the recommendations in the RCP report there is evidence that sunscreens make no difference to the incidence of melanoma. Indeed, there has been for some time proof that they may even contribute to causing skin cancer, as well as certainly helping to trigger off photosensitivity - skin rashes in response to sunlight. [12] When Apperley, who showed that cancers in general decreased with sunlight exposure, looked at the incidence of skin cancer throughout the continental USA, he found the relationship with sunlight depended on the average temperature. Over a critical level of 42 C, increases in exposure to sunlight clearly caused an increase in the rate of development of skin cancers - of all types. Below that temperature, however, the rate decreased with increasing exposure to sun.[13]

It would appear, then, that in hot, tropical countries there is a risk of sunlight causing skin cancer, particularly in white skins, of course. In temperate climates such as northern Europe, on the other hand, sunlight is likely to protect. This would also tie in with the finding that, in contrast to Panner's figures mentioned in the last chapter, English researchers have found that rates of skin cancer and total cancers vary together.[14] In temperate climates such as ours, sunlight may protect us from both skin cancers and cancers in general, while in hot climates it may encourage skin cancers (basal cell and squamous cell), but still protect against other cancers.

The overall picture, then, seems to be that sunlight in large doses for long periods may cause skin cancer, particularly in the tropical heat, but sunlight at any dose level protects from cancers in general. The more sunlight you receive, the better protected you are. We know that sun burning with its production of free oxidizing radicals is the factor that encourages the development of skin cancer. There is no reason to think that this is the protective factor against other cancers, so the way to take your sunlight as a cancer protection is in frequent small doses, insufficient to burn you. The secretary who slips out of the office at lunchtime and sunbathes in the park for forty minutes has the right idea. As well as gorgeous brown legs, she is giving herself protection against cancer.

 

Atmospheric filter

The wavelengths that are responsible for sunburn are those with the highest energy content - ultraviolet. Because their wavelength is shorter, there are more waves per meter of length, or per second, hitting the skin, and therefore more energy is transferred. Compared to ultraviolet, infra-red has a very low energy content. The whole of our biology is based round the fact that there is a very sharp cut-off point for ultraviolet transmission through the atmosphere.

There are two gateposts framing the narrow inlet for solar radiation. On the low frequency, long wavelength side, much of the solar spectrum is absorbed by carbon dioxide and water, while on the short wavelength side the most important absorber is ozone. It is the fact that ozone absorbs best at a wavelength of 260 nanometers, and the absorption then tails off completely above 300, that gives us the cut-off point for solar radiation at around 300 nanometers.

There has been concern among scientists in recent years about the danger that certain environmental pollutants, particularly the propellants in aerosol cans, may destroy the ozone layer in the atmosphere and lead to an increase in the amount of ultraviolet reaching the earth. However, the ozone level varies greatly from hour to hour and from day to day, in response to normal environmental and weather factors. The level of ozone in the atmosphere has been measured for over fifty years in the Swiss Alps, and in some other places, and no clear trend has been demonstrated so far. This is true notwithstanding the finding of an apparent 'hole' in the ozone layer above Antarctica. Although such a discovery suggests that our environment is being disturbed by man's activities, it is still a local phenomenon and does not appear to reflect a general reduction in the ozone layer - yet. Indeed, some scientists think that it may always have been there and we have only just noticed it.

エロ Smog

Pollution from car exhausts and industry produces a range of chemicals in the atmosphere, including both the components of acid rain (sulphates and nitrates in particular), and indeed ozone itself. In this circumstance, with a very high local concentration at just above ground level, ozone is more important as a toxic pollutant than as a sunscreen. In fact, the level of ozone in smog appears to be increased by ionization triggered by ultraviolet light. Monitoring of the intensity of sunlight in Washington DC and California has shown a reduction in the sunlight reaching the earth of more than ten per cent over the last fifty years, with a twenty six per cent reduction in the ultraviolet fraction.[1] The only evident cause of this is environmental pollution.

Therefore, if you live under a smog, as many people in cities around the world now do, you receive less ultraviolet light because it is absorbed by the smog. You also breathe less fresh air and more pollution. Once again, modern life has increased the toxic component of our intake while reducing the nutritional or beneficial component. In this case, it appears that ultraviolet light helps to make the problem worse by interacting with the chemical components of smog. But the real culprit is not the ultraviolet light, it is the products of fossil fuel combustion that go to make up pollution.

エロ Photo reactivation

It is ultraviolet light of around 295 nanometers wavelength (UVB) which has the potential to cause damage to DNA and other molecules. These are the shortest wavelengths - and therefore have the highest energy - of any light reaching the earth. Thus they have the greatest potential for transferring energy to our bodies - for producing either benefit or damage.

Damaged DNA may lead to a cellular mutation - an abnormal cell which can be the start of cancer, or in the next generation of a genetic change or a congenital abnormality. Although several people have suggested that this is necessary for evolution, that an element of randomness is needed to keep things changing, it is certain that the process does lead to cancers and deformities. Under normal circumstances, all such genetic mutations are filtered out of the body by the immune system.

When cancer develops this is detected at an early stage by the immune surveillance and the cells are killed and removed. Clinical cancer is therefore more a sign of an immune problem than of something unusual in the way of genetic events. Transplant patients who have received immunosuppressant drugs so that they will not reject the transplanted heart or kidney have an eighty times greater than normal chance of developing cancer. AIDS sufferers also have a tendency to develop unusual forms of cancer such as Kaposi's Sarcoma. Both groups have in common a low level of immunity to infections and to cancers.

But it has always been known that some organisms have the ability to repair DNA damage in a manner that is dependent on ultraviolet light. Many micro-organisms have been shown to contain a protein molecule - an enzyme - which absorbs near-ultraviolet light (UVA), and is thereby activated to repair broken strands of DNA. [17]

The chemicals that are measured as an indicator of DNA damage are known as pyrimidine dimers. These are small component molecules of DNA which have been broken free of the chromosome and then joined together in pairs to form dimers (which consist of two identical molecules). Evidence of repair of DNA damage is obtained if these dimers are split into two monomers again. The process by which this occurs in response to UV light is called photo reactivation. It has always been known that it occurs in small organisms, but until recently it was thought that higher airmails did not perform this function. In the past decade there has been increasing evidence that it occurs in a range of mammals, and the hunt was therefore on for evidence of its occurrence in humans.[18]

In 1986 Betsy Sutherland, a researcher at Brookhaven National Laboratory in New York, finally demonstrated that photo reactivation occurred in human skin. She described its parameters quite clearly: it is light-dependent, being stimulated best by light of wavelength 350 to 400 nanometers, which is in the near ultraviolet range. When such light hits the skin, the process happens very rapidly, clearing most of the dimers out of the tissue within minutes.[19]

There is also some non-enzymatic repair that is still dependent on light, but occurs by chemical reactions that do not depend on human enzymes. Although this can be measured in skin also, it occurs at a much slower rate, taking about an hour to remove half of the dimers. Clearly it is less important than photo reactivation.

The remarkable fact is that although ultraviolet stimulates synthesis of DNA, and therefore cell activity and multiplication, it suppresses DNA synthesis during the first hour after exposure.[20] During this hour, the photo reactive enzymes are able to repair most of the damaged DNA in readiness for the burst of cellular activity that then occurs. Therefore, as welI as having a potential for damaging human tissues, ultraviolet light is also essential for the repair of such damage. We are so well adapted to our solar environment that there is a built-in protective mechanism, triggered by sunlight, to protect us against the possible harmful effects of this same sunlight.

The message seems clear. Although some doctors and scientists are still determined to prove that sunlight is damaging and should be avoided, the evidence is mounting in its favor. We are designed to feed on sunlight, and we suffer if starved of it. But changes in our lifestyle over the past few decades have only advanced a process started by the industrial revolution, driving us indoors and away from the sun. Attempting to rectify this by brief binges of sunlight for a fortnight in the summer may well have harmful effects that offset their benefits. We should aim to nourish ourselves with sunlight regularly, every week of the year.

 

 

Chapter 8

エロ Invisible radiations

One of the more ironic aspects of science is its ability to deceive itself into believing that scientific progress is reasonable, logical and inexorable. Scientists are taught that the 'scientific method' - the process laid down for the development of scientific knowledge - has the power and status of a force of nature. Careful observation of the available facts is followed by the formulation of a hypothesis. An experiment is set up to prove or disprove this hypothesis, and the results lead to the development of a better hypothesis, and a new experiment, and so on.

Unfortunately, this does not always work. Many ideas are stillborn because scientists, being only human, find it difficult to consider something that does not meet their preconceptions. Others die young, because a new and more exciting discovery is made which pushes them out of the spotlight of scientific interest. Such a fate, it seems, befell the study of the phenomenon of invisible radiation by organisms, which we shall now call bioradiation. It remains unheard of by most scientists, and the advances in technology since it was first described have hardly been applied to thoroughly examining and proving or disproving it. Yet its implications are so great that it could change all our lives radically.

エロ The living wave

優良エロ画像 For some years now we have known that the Russians are many years ahead of the West in their investigation of telepathy, psycho kinesis and paranormal phenomena of every sort, together with the Eastern disciplines of acupuncture, traditional Chinese medicines and herbs. So it has been with bioradiation. Although in the thirties there were a number of studies in Europe and America, it is in Russia that all the donkey-work has gone on. Dozens of papers have been produced, and the baton of research has passed down to successive generations of the same family which made the breakthrough over sixty years ago. Indeed, the Russians still publish on bioradiation; the most recent study I can find was published in 1982, by a descendant of Alexander Gurwitsch.[1]

In 1923 Gurwitsch found that he could stimulate the growth of cells, and their division, by exposing them to radiations from an already growing organism.[2] In his first experiments, be used onion roots. These were arranged in glass tubes enveloping most of their length, so that only the parts needed in the experiment were exposed. On the side of the detector root nearest to the transmitter root, more cells divided, and there was an increase in size and chemical activity.

His first assumption, or hypothesis, was that this was due to a chemical substance released from the transmitter root. So he inserted a quartz sheet between the two roots to block any such mediators, and found that the effect was not abolished. When a sheet of glass was interposed instead, however, there was no response by the detector root. Since the effect could pass through quartz, it had to be an electromagnetic wave; but if it could not pass through glass, then it was almost certainly in the ultraviolet part of the spectrum.

エロ Life monitor

優良エロサイト Over the next decade this experiment was repeated in a variety of different organisms, ranging from staphylococcus bacteria, through yeasts and plants, to human blood, excised human cancers and bone marrow.[3] AII of them showed biological radiation. However, the tissues of animals or humans that were near to death did not show any radiation. Nor, it seemed, did any human tissues with the exception of brain, blood and muscle. It was several years before later, more carefully designed, experiments showed that all tissues radiate, but some of them at a much lower intensity than others.[4]

The degree of radiation appeared to depend on what was going on in the organism or tissue. Cells which were in the process of growing and dividing radiated most, and cells in a state of exhaustion radiated least. In fact, the radiation detected from human blood was highest when the individual's energy level was high, and at its lowest after a day's hard work. Blood from anybody with a serious illness did not radiate well, and the most dramatic difference was found with cancer patients.

The lack of any radiation from the blood of people with cancer was so striking that the researchers came to regard this as a reliable test for cancer, and many cases of previously undiagnosed cancer are reported to have been detected by this method., When they took samples from the malignant growth itself, on the other hand, they found that it radiated very strongly. They reported that it seemed as though the cancer had all the vitality and had somehow taken it away from the rest of the body.

エロ Atomic power

The background to mitogenetic radiation is simple biochemistry and physics. An atom is made up of a nucleus in the center, around which electrons orbit in fixed patterns - at least this is one of the conflicting explanations used by science. When electrons are moved from orbit to orbit they either emit or absorb electromagnetic radiation. The wavelength of this radiation is precisely linked to the orbit of the electron; it has to contain exactly the right amount of energy to shift the electron from orbit A to orbit B - no more and no less. For many of the common biochemical reactions in the human or any other living body, the wavelengths fall within the ultraviolet.

When this radiation is passed from one living cell to another, it appears to be able to stimulate the very same set of chemical reactions in the receiving cell. In fact, the pattern of wavelengths emitted by any one cell can be regarded as a distinctive bioradiation fingerprint. It would certainly enable us to determine the precise origin of the cell, and probably also its state of health and functioning. It will also, naturally, produce the best response in cells of the same type as itself, and may even be damaging to cells of different species.

It is this property that may enable bioradiation to control the growth and development of a plant root, for instance, keeping it distinct and successful despite all the different cells from different organisms that surround it. It could, perhaps, enable bioradiation to determine the whole course of development of the embryo of a frog, a camel or a human from unicellular organism into finished animal.

The next key finding was that bioradiation could be triggered off by exposing cells to a source of ultraviolet light. When a carbon-arc lamp, the 'black light' familiar from detective stories, which was the only source of UV available in laboratories at that time, was directed at a preparation of cells, they not only produced their own bioradiation in response, but an increase in metabolic activity followed as well. The implication is clear: UV from natural, sunlight sources must be equally able to stimulate our metabolisms.

Radiating health

The progress of such work in the early years was slow. In order to measure the amount of energy emitted at different wavelengths from a single chemical process, it was necessary to do a series of single experiments, each allowing through only a small waveband. The energy transmitted through a narrow-band light filter was measured by assessing how much growth it stimulated in a suspension of organisms. Alternatively, the increase in a chemical reaction could be measured. Nowadays it is possible to measure the energy directly, using a photo- electric cell.[7]

Despite these constraints, two remarkable properties of bioradiation were discovered. The first is that the secondary radiation (the energy put out by an organism or solution in response to an input of ultraviolet energy) became stronger the more dilute the solution. Thus a 0.02 per cent solution of nucleic acid produced its peak effect in one fifth of the time taken by a 1 per cent solution. Similar results were found with suspensions of bacteria.[8]

This, of course, is very reminiscent of the response pattern of homoeopathic remedies. It is interesting to speculate that there might be a connection between bioradiation and homoeopathy. It might bring us a step nearer to understanding this mysterious and paradoxical therapy.

Acupuncturists too should be very interested in the field of bioradiation, as the whole of acupuncture is based on the concept of invisible 'chi' energy, which is essentially the life force. They say that 'where the chi goes the strength follows', meaning perhaps that biological radiation is necessary to stimulate the growth and division of cells, and their continued effective functioning. Certainly, it was realized by the early researchers that one of the most effective ways of getting a cell to radiate was to traumatize it mechanically; and the principal treatment method in acupuncture is the insertion of tiny needles through the skin, which will definitely traumatize the cells that are hit. Perhaps the whole therapeutic effect of acupuncture is mediated through bioradiation.

A further remarkable property of bioradiation is that of amplification. When six quartz test tubes containing bacteria were set side by side, and the first one was irradiated with UV, there was a secondary radiation emitted from the other end of the row, which was twenty seven times greater than the input UV.[9] This means that any living organism may be able to act as an amplifier that intensifies the signal as it is transmitted through its cells. Bioradiation is not something that can be transmitted over long distances from one human or animal to another, for good or damaging effect. When radiating through a gas or liquid devoid of life, bioradiation will soon be dispersed and wasted without effect. But within our bodies, even in response to an appropriate stimulus from outside, it might just turn out to be one of the most powerful life forces there are.

We can take in the relevant energy in the most simple and primal method, known to all organisms. We can sunbathe. This allows the blood as it passes through the capillaries in the surface of the skin to be gently bathed in ultraviolet and all other wavebands of light. The energy thus obtained can be transported in the red blood cells, and emitted over the next few days.[10]

There are far too many beneficial effects from sunlight exposure for them to be entirely explained by the pineal effects and vitamin D synthesis. Bioradiation could provide an explanation for some of this, and enable us to start to make sense, at last, of man's psychological and physical need for sunlight.

 

Chapter 9

Intravenous Sunlight

In 1928 a sensational new technique was introduced, which looked like revolutionizing medical practice. This simple treatment appeared to be able to cure many severe and even terminal bacterial infections rapidly. It succeeded in killing viruses that were unresponsive to any other therapy, and cleared toxins from the blood within days that might otherwise have been fatal. What was more, it appeared to increase the oxygen-carrying capacity of the blood by 50 per cent, and to cure a number of conditions, from asthma through paralytic ileus (a failure of the bowel activity) to thrombophlebitis, that were otherwise untreatable. Yet ten years later, penicillin was discovered, and a few years later this therapy had sunk without trace.

The technique was straightforward: ultraviolet irradiation of the blood. A needle was inserted into a vein to remove blood, which was passed through a treatment machine and a pump, then back into the same vein, in a manner almost identical to modern kidney dialysis machines. The treatment component was very different, however. In a chamber within the irradiation machine, blood was exposed for a controlled time and intensity to ultraviolet light from a mercury-quartz bulb.

 

Light transfusion

Much of the work on developing this treatment was done at the Hahnemann Medical College in Philadelphia. This medical school was established to train doctors in conventional medicine, but with homeopathic skills. Throughout the 1930s and 40s, thousands of patients were treated with light transfusion. Even where contemporary chemotherapy had proved quite ineffective, the Knott technique, as it came to be known, after Dr E. K. Knott, who refined the therapy, produced dramatic results. The lives of many patients with bacterial infections were saved, including cases with generalized septicemia who were near to death.[2] These results are very similar to those achieved with the most modern and sometimes intravenous antibiotic therapy nowadays - and they carried none of the ill effects that we now know antibiotics to have.

The one disease that did not respond to treatment with light transfusion was a severe infection involving the heart called bacterial endocarditis, Even now, this is regarded as a grave illness with a serious risk of mortality, and a high proportion of damage to the heart in those patients who survive. Unless treated rapidly and vigorously, patients invariably die.

Even more exciting, particularly to us in the 1980s, is the effect that was achieved with viral infections. Doctors treating a range of infections from viral pneumonia, through mumps to acute poliomyelitis, found that the illness cleared within days, and the abnormal temperature, blood cell counts and physical signs were corrected.[3] This achievement has yet to be matched by modern medicine. Antibiotics are ineffective against viruses, and although there are several antiviral drugs on the market now, none of them has an effect which could be termed dramatic - except by advertising copywriters.

All of this becomes especially important in the light of the contemporary AIDS crisis. Because scientific medicine has no effective treatment for AIDS, many people who find that they have the infection are paralyzed by fear, which can destroy their will to fight the disease and may even damage their immune system directly. This can only accelerate their deterioration and death. If ultraviolet light in any shape or form offers hope of effective treatment for viruses, including AIDS, then we should examine it urgently.

In 1986 I visited the St Petersburg, Florida, clinic of Dr William Philpott, who is one of the most respected physicians practicing nutritional medicine in the world today. He has, in collaboration with some German workers, developed a technique of ozone therapy which has striking similarities to the Knott technique. About 250 cc's of blood is removed from a vein and mixed with ozone, produced by a commercial ozone generator such as may be found in laboratories and in swimming pool treatment plants. The blood is then returned to the body through an ordinary intravenous drip.

It has been known for years that ozone can replace chlorine in swimming pools. Ozone has an even better profile of cleansing and germ-killing effects; it has no unpleasant odor and does not irritate the eyes - not to mention that some people develop allergies to chlorine. Dr Philpott says that by injecting ozone intravenously we are applying a powerful oxidizing agent, and micro-organisms are at least ten times more vulnerable to oxidation than humans. So as well as boosting oxygen levels in the blood, ozone therapy should kill off infections directly.

These effects are clearly similar to those of the Knott technique. There may well be similarities between the two mechanisms, such as that part of the impact of the Knott technique is through oxidative effects of ultraviolet light. However, we have the evidence of the work of Gurwitsch and others on ultraviolet transmission by cells or bioradiation .[4] From this it is clear that intake of ultraviolet light can have powerful effects on metabolism and on health. It can stimulate oxidation - and also reduction, glycolysis, proteolysis and a range of other enzymatic processes. It can cause cells to divide and multiply, accelerating wound healing, stimulating the release of new blood cells from the bone marrow and encouraging the production of cells and of antibodies by the immune system. Ultraviolet irradiation of the blood, either by the Knott technique or by simple exposure of the skin to sunlight, nourishes and heals our bodies - like the food that it is.

 

Germicidal light

In 1877 two scientists called Down's and Blount reported in the Proceedings of the Royal Society that sunlight had the effect of killing bacteria.[5] Their chance observation arose when solutions of sugar water left on the windowsill became cloudy in the shade, but remained clear in the sunlight. When the two solutions were examined under a microscope there were bacteria growing in the cloudy one, which bad been in the shade, but none in the sunlight-exposed tube.

Over the next thirty years it was established that the ultraviolet component of the solar spectrum had this effect, and that it was effective in killing off a number of the most important micro-organisms then known to science. These included anthrax, cholera, dysentery, the plague and tuberculosis. In 1903 the Nobel prize was awarded to Niels Finsen for his demonstration that sunlight therapy could treat tuberculosis of the skin. Within a few years sunlight was also being used for tuberculosis anywhere in the body, and a number of sanatoria were set up, in the countryside of England and other nations, but especially in the Swiss Alps, to treat tubercular patients by this method. By all accounts, their results were good.

 

In the air

A sufficient dose of ultraviolet will kill any living cell.[6] That is why spacemen have to be protected from it. However, only a fraction of this UV reaches the earth's surface. Seasonal and weather factors come into play too; there is between two and two and a half times as much sunlight in summer as in winter. Also, the shorter the wavelength, the more the light is scattered by the atmosphere, and UV has the shortest wavelength of any light reaching the earth. As a result the summer/winter ratio climbs with UV of wavelengths below 350 nanometers to a factor of four, and below 300 nanometers there may be no radiation around in winter at all.[7]

Nevertheless, there should be enough UV in sunlight all year round, on average, to kill the large majority of bacteria and moulds within an hour. Just as lichen only grows on the northern sides of trees, so micro-organisms have to find dark and preferably damp places in which to thrive. Moulds in houses require a certain percentage of humidity in order to survive at all, and of course sunlight dries them out. Wet bacteria and moulds are about four times more resistant to ultraviolet killing than dry ones.

As the diagram shows, all bacteria and moulds are susceptible to killing by UV. Viruses have a wider range of susceptibility, some of them being inactivated by the same amount of UV that kills bacteria, but others being up to two hundred times more resistant. Nevertheless, if you can give them enough, it will kill them.

The AIDS virus has approximately the same sensitivity as most moulds. Nearly all toxins, such as those excreted from staphylococcus, diphtheria, and tetanus organisms, are also inactivated by UV - as are, remarkably enough, all snake venoms.[8] This does not mean that we can use UV to inactivate them once they are inside the body; we can't guarantee light reaching that far. But it does mean that in areas that are subject to dampness or mould, or where infection is a serious problem, UV can be used to kill the organisms.

 

Building with light

In Sweden, every building must have adequate nuclear fall-out shelters for all the people in it. Consequently all new 'homes and offices - even churches - have large cellars with several feet of concrete protection and heavy lead-lined doors. Naturally these rooms are used normally for a variety of purposes - as storage, or meeting rooms, for example. But in the long cold Scandinavian winters, the problems with lighting and ventilation can lead to a build-up of mould in underground rooms. Swabbing down with bleach or other chemicals can often kill the mould, but without inactivating the mycotoxins that they produce, which may linger and continue to cause damage to health. For this reason, health campaigners in Sweden have become interested in using full-spectrum lighting in such rooms, in order to kill the moulds and destroy their toxins simultaneously, as well as providing a healthy form of illumination.

Since most organisms get into our body from the air, and in dust on the skin, environmental ultraviolet light is clearly important in keeping down the rate of human infection in general. Out of doors this will happen naturally, but within buildings it may be necessary to use an artificial source of UV. There have been a number of studies that have shown that this works. One in school classrooms in Uppsala, Sweden, found that the bacterial count in the air went down 50 per cent when UV lights were installed;[9] the same effect was found in a US Navy barracks.[10] Both of these studies also found that the rate of infection among the children or the recruits went down by between about twenty five per cent year-round, and by thirty five per cent in winter, at the peak time for such infections, On the other hand, a study on students at the University of Illinois found as much as a fifty per cent reduction in colds when the subjects themselves, rather than the air they lived in, was exposed to UV light.[11]

Sad to say, Russia is the only country that appears to be making wise use of this effect now; ultraviolet light is used in schools and factories to improve fitness and reduce infections throughout the winter.[12] The amount of unnecessary suffering that is caused by our failure to perceive and use these health effects of ultraviolet light is preposterous.

 

Surgical intervention

In 1935 it was shown that using ultraviolet lights in a surgical operating theatre could kill all bacteria within ten minutes, even though it would take one and a half hours for the most sensitive skin to go red.[13] Over the next five years, surgeons at the Duke Medical Center in North Carolina published several papers on the use of UV in decontaminating the air in the operating theatre. They found that the number of airborne bacteria was cut by over fifty per cent.[14]

Subsequent studies found that it was also possible to reduce the rate of postoperative infection by about fifty per cent - although only in certain groups of operations. This probably makes sense; it would be absurd to suggest that other factors, such as the general health of the patient, did not play a part. To this day there are some surgical teams in America and Canada who still use UV light, especially in orthopedic and neurological procedures, where an infection can have devastating results. They remain persuaded that it helps to reduce the problem.[15] And nobody has found any evidence that it harms the health of patients or staff in any way - which is more than can be said for antibiotics.

The overuse of antibiotics appears to have bred a new generation of super bugs which are resistant to nearly all available antibiotics. This has led to a lucrative race between drug companies to produce newer and more lethal antibiotics. Unfortunately, there is no sign of a cure to the problem yet. If hospitals installed low-intensity ultraviolet lights and left them on for most of the day, they might well achieve a major reduction in this problem. The fact that they would improve the health of their patients in several other ways at the same time would simply be a bonus.

 

On the skin

The second level of defense is on the surface of the skin itself, and is due to the same free oxidizing radicals as in ozone therapy, but in a different form. In this case it is the lipids or oils in the skin which provide the oxidizing effect. In 1936 an elegantly simple experiment showed that when skin was exposed to ultraviolet light for eight hours, the 'active oxygen content' went up by 10-15 fold.[16] It was then demonstrated that a large part, at least, of this oxygen was in the skin lipids or fats. These lipids were sufficiently 'active' to fog a photographic plate, and they killed hemolytic streptococcus, a relatively nasty micro-organism, in just a few hours. When a solution of cysteine, which is a well-known antioxidant nutrient, was added to the experiment, then the killing effect was slowed down but by no means abolished.[17] We know from this that it was an effect due to free oxidizing radicals. The same effect was achieved with the skin lipids, of course, by exposing them to ozone.

it seems that even without ultraviolet light, skin lipids will take up some oxygen from the air and use it to kill bacteria. However, this effect is much more intense under UV. Since ultraviolet light or sunlight will have a direct effect itself by killing off the organisms on and near the skin, there is clearly a double impact in this layer of defense. But both components are lost to those who stay indoors, for example in hospitals, or who cover their wounds with bandages and dressings. it would appear to make more sense for the nurses to wheel patients outside into the fresh air and remove their dressings to expose them to whatever sunlight there may be.

Now that we have conquered the majority of bacteria (outside hospitals, that is) the two infective agents that are causing the most problems are viruses, from AIDS to influenza, and fungi. Chronic fungal skin infections such as athlete's foot and ringworm are a continuing problem, but the real growth area is an organism called candida. We have known for forty years that direct ultraviolet light kills viruses and fungi. In this country we have never fully applied this discovery.

Usually thought of simply as the organism that causes a vaginal infection called thrush, candida came to prominence when it was found that it could also cause generalized infections in patients whose immune systems had been suppressed in order to allow a transplant to take. Although severe for the sufferers, this problem is small in volume. But it is now becoming clear, thanks to the work of Drs Orion Truss and William Crook in the United States, that candida is a much bigger problem.[17] Due to the increased use of antibiotics, not only to control infections but often in agriculture to prevent infections of stock animals, it is likely that we all now carry a level of antibiotic in our blood.

As well as killing off pathogenic (damaging) organisms, antibiotics also kill off the normal organisms that live in our bowel and are necessary for the process of digestion and absorption of food. It is at such moments that the candida and other fungal infections, which are less inhibited by antibiotics, can breed in the gut. When it gets a foothold in this way, candida can become a chronic problem and have a damaging effect on the immune system. It is certainly one of the factors, and maybe one of the important ones, that contribute to people who carry the AIDS virus developing the full AIDS syndrome.

One of the notable characteristics of candida infections is that they are often worse in humid conditions (fungi need humidity in order to survive) and in winter, when less light is available. Sunlight therapy can have a dramatic curative effect on athlete's foot and other skin fungi." It also appears to be beneficial in many cases of candida infection, and in post-viral syndrome. Clearly it can be a valuable ally in the fight against fungus.

We know that sunlight helps to protect us from infective organisms at three levels: in the air, on our skin and within our bodies. We are not dealing here with a chance effect of solar radiation but with a major part of the fabric of our world, and one on which we depend in many different ways. If we ignore it or shun it, we do so at our peril.  

 

Chapter 10

Acquiring immune efficiency

With the discovery - or is it the invention? - of photo-immunology, we now have to realize that the skin is one of the most important organs of the body. Apart from the fact that we live through our skin - we feel with it, we kiss with it, we give off visual and odor signals with it - the skin is an essential part of the immune system. It appears that there are several different types of cells in the skin which trigger immune responses. The existence of these cells has only been known about for half a dozen years, so we certainly do not have a detailed picture of how they interact. We know enough to appreciate that it is complex, and - this should come as no surprise - that such cells are very sensitive to the effects of light.

For the immune system to prepare antibodies to attack an infection or other threat, it first has to recognize the invader and produce a line of T-cells which are specific for it. These are the white cells which are attacked by the AIDS virus. In the course of their development, they can either become T-helpers, which stimulate the immune system to attack a suspected threat, or T-suppressors, which subdue that attack. The key measure which is used by immunologists is the helper/suppressor ratio. This may be high in allergies and in acute infections, when the body is trying to mobilize the immune system to fight what it sees as an attack. A low ratio and therefore too many suppressors can cause lowered resistance to infection, and even to cancer. In AIDS the ratio is often very low, as the T-helpers are killed off by the virus more rapidly than the T-suppressors.

 

Formal introductions

Before either T-helpers or suppressors can be produced in response to an antigen, such as infecting organisms or potentially allergic foods or inhalants, the antigen has to be introduced to them. This very British transaction is performed by a category of cells known as antigen presenting, or AP cells.

The skin contains two different types of AP cells. The first type, the Langerhans cell, stimulates the production of T-helpers.[1] The Granstein cell, on the other hand, leads to the production of T-suppressor cells.[2] Both types appear to be killed - or at least have their effect blocked - by ultraviolet.[3] The Langerhans are more sensitive than the Granstein cells, so a low dose of UVB can probably reduce the immune response. However, this refers to studies that were done on narrow-waveband light, and the maximum effect appears to be at around 297 nanometers. Since this is almost exactly the cut-off point for radiation reaching the earth's surface (the rest is filtered out by ozone in the atmosphere), there seems to be little or no risk of a damaging effect from ordinary sunlight, even on tropical mountains, in broad midday sunlight, in summer.

 

Light nourishes the immune system

On the other hand, there is another category of cell in the skin called keratinocytes. These do not present antigens, but they do appear to produce a chemical known as interleukin-1 or IL-1 .[4] The name is unimportant, since it has been known by at least half a dozen other names in the time that we have been aware of it. What is important is the effect; it stimulates T-cells to reproduce and increase in number. In contrast to the relatively slow process of antigen presentation, the development of new antibodies and of a viable immune response, which may take up to a fortnight, the response to interleukin-1 takes only a few hours.[5] It mobilizes the immune response to all sorts of external factors. We now know that although exposure to monochromatic (narrow-waveband) ultraviolet light may kill off the cells that produce this chemical, broad-spectrum light, even simply the full waveband of ultraviolet light, appears to stimulate its production.[6]

Since the experiments that show suppression were done with light of 270 NM, which is never obtained naturally from sunlight, we probably need have no fear of sunlight damaging our immune system at all. But we can make use of the stimulating, IL-1-producing effect of light to assist our immune systems in keeping us well.

This response to sunlight probably explains the observation by Dr Frick in 1974 that exposure to ultraviolet light raises the number of white cells in the blood, increases the ability to deal with infections and improves general health.[7] This is backed up by some Russian studies which found that the ability of white cells to deal with infections is approximately doubled by ultraviolet light.9 They now use this in schools and factories, and naturally in their long dark winters it is able to show a substantial reduction in health problems.

The only opportunity that we in the UK have to look at sunlight deprivation of similar severity is in the case of scientists on the Arctic and Antarctic standing bases operated by all the major powers. It is a recognized fact that men returning from expeditions or tours of duty on the polar ice-caps, where sunlight is in short supply at times, develop upper respiratory infections in large numbers on reentering 'civilization'. Studies on their blood show that their white-cell counts go down substantially during the arctic winter.

 

Keeping the balance

Since so much immune function seems to originate in the skin, and since vitamin D is also manufactured in the skin, it is interesting to speculate whether there is a connection. The evidence in this direction is a tease: it raises the interest, but gives nothing tangible. In 1984 a study in Japan looked at T-helper and T-suppressor levels in osteoporosis, the bone-loss disease associated with ageing. The researchers reasoned that osteoporosis is likely to be an immune dysfunction, since it occurs with ageing - as do many immune problems; it occurs in rheumatoid arthritis, which is known to be an immune disorder; and it is more common in women, particularly around the time of childbirth and after the menopause. They found that the ratio of helper to suppressor cells was fifty per cent higher in osteoporotic patients.[9]

They then gave these patients vitamin D for two months, and found that this brought down the T-helper/suppressor ratio in every case to around the normal. In people of the same age without osteoporosis, who had a normal T-helper/T-suppressor ratio to start with, vitamin D does not alter this. It seems then that vitamin D brings raised T-helper/suppressor ratios back to normal, and reduces the allergic tendency that results from them.

Since ultraviolet light also has an effect on the immune cells in the skin, both regulating the ratio and increasing the total number of white cells, we are left wondering just how important an immune regulator vitamin D may be, and how dependent we are on sunlight for a smoothly functioning immune system. It stimulates the immune response, but at the same time provides the means for controlling and regulating that response. Without it, it seems, we run a much greater risk of a disordered immune system. With it, we can keep our immunity running like a well-tuned engine.