Tomato stops wrinkles, prostate cancer, boosts sperm quality, researchers find
Lycopene supplements may protect from ‘ageing’ infrared A rays
THE recent heat sent many of us reaching for the sunscreen. But now, some experts are warning this may not protect us against a potentially harmful sunray: infrared.
Conventional sunscreens are designed to block out ultraviolet light – UVA and UVB – the rays that damage and burn the skin. However, these products do not block out infrared rays.
These rays, which were discovered in 1800, transmit heat, raise skin temperature and are responsible for the warmth you feel when sitting in the sun.
Infrared rays make up to half of the sun’s energy (UVA and UVB combined make up between five per cent and seven per cent) and one type in particular, infrared A, can penetrate the deepest layers of the skin – deeper than ultraviolet.
Recent research in animals has suggested infrared A may play a role in skin cancer when combined with exposure to UVB. Infrared A may also contribute to ageing of the skin – scientists suggest it alters some of the biological processes involved in maintaining healthy skin cells, affecting the production of collagen, the protein that acts as scaffolding for the skin.
This could ultimately result in wrinkles, sagging and ageing. The possible link between infrared A and cancer was first noted in the Eighties. However, more recent research at the University of Kiel in Germany found that mice exposed to UVB and infrared A rays together developed faster-growing skin cancer tumours than those exposed to UVB light alone, though those exposed to infrared A alone did not.
So, how can you protect yourself? Dr Lowe takes lycopene (an antioxidant found in tomatoes and red fruit) and co-enzyme Q10 supplements, and wears UVA/ UVB sun protection cream.
Also, another study published last year found that just ten helpings of tomatoes a week could help men reduce the risk of prostate cancer by almost a fifth.
Researchers think that protection against the illness comes from a key chemical inside the fruit known as lycopene. Tomato-based pasta sauce, tomato juice and even baked beans and the tomato puree topping on pizza were all found to have a beneficial effect.
Scientists say men who doubled their intake of fruit and vegetables to the recommended five portions a day reduced their risk by nearly a quarter.
In the first study of its kind, researchers from the Universities of Bristol, Cambridge and Oxford examined the diets and lifestyles of nearly 14,000 men aged 50 to 69.
They found that those who ate at least ten portions of tomatoes a week were 18 per cent less likely to develop prostate cancer compared to those who had none, or very few. One portion counted as 150g of tomatoes, half a tin of baked beans, a portion of pizza with tomato puree, tomato-based pasta sauce or a glass of tomato juice.
However, the researchers urged men not to overindulge in baked beans, pizza and pasta sauce as they can contain high levels of salt. Meanwhile, an earlier study suggested that certain vegetables such as carrots, lettuce, spinach and tomatoes could help improve sperm quality; sperm motility – how quickly a sperm can swim towards an egg and sperm morphology – the size and shape of a sperm (for the best chance of successfully conceiving, a sperm should have an oval head and a long tail).
The study published in the peer-reviewed medical journal Fertility and Sterility noted that sperm quality could also be improved by quitting smoking if one smokes, trying to achieve or maintain a healthy weight, drinking sensibly and keeping the testicles cool.
The researchers from Harvard School of Public Health and Universities in Canada, Copenhagen, Murcia and New York, a study funded by a grant from the National Institutes of Health and the European Union looked at young men’s diets and analysed their sperm samples.
They found that men who ate a higher amount of three antioxidants found in fruit and vegetables had sperm with better motility and morphology.
The three antioxidants in question were: beta-carotene – found in carrots, lettuce and spinach; lutein – found in lettuce and spinach; lycopene – found in tomatoes.
According to the study, men who ate higher levels of beta-carotene and lutein had a 6.5 per cent increase in sperm motility, and those who consumed higher levels of lycopene had 1.7 per cent improved sperm morphology. However, this study examined diet and sperm quality at the same time, so cannot prove cause and effect.
Also, the study involved young healthy men so the results may not apply to different populations. “Still, increasing your intake of vegetables is unlikely to harm you or your sperm and has many other health benefits.”
Dr. Nick Lowe, a consultant dermatologist at London’s Cranley Clinic, says: “There’s no conclusive link between infrared A exposure and skin cancer as there is with UVA and UVB rays, but there is emerging evidence that they may be involved in some way when combined with UVB.”
When it comes to skin ageing, the evidence is stronger, according to Professor Jean Krutmann of the Leibniz Research Institute for Environmental Medicine, in Dusseldorf, a world authority on infrared A. “Infrared A damages the skin deep down by interfering with enzymes that maintain healthy skin renewal,” she says. “This means more collagen is broken down than is replenished, resulting in premature ageing of the skin and loss of elasticity.”
Professor Krutmann recently received a grant from the German Ministry of Science to use a new type of lamp that can mimic the amounts of UVA, UVB and infrared A found in natural sunlight to carry out further investigations in mice. Lowe adds: “We’ve known since the Seventies from research on animals that infrared rays, and heat in particular, produce changes in the skin, including increasing the size of blood vessels and permanently affecting the elasticity of tissues. “Research suggests repetitive exposure may lead to development of thread veins and wrinkles more common in ageing skin.”
Crucially, though sunscreen products usually contain protection against UVA and UVB, there is no ingredient that has been proven to offer the same barrier protection against infrared A. When suncreams were introduced in the Thirties, they only helped protect against UVB rays.
It wasn’t until the mid-Nineties that UVA rays were recognised as causing skin cancer, too, and filters were added to sunscreens. “This may be what will happen with infrared A rays, too, but we just don’t know yet,” says Lowe.
The one major drawback, he says, is that there is no chemical filter that has been proven to block the effects of infrared. “However, some antioxidants, including vitamins C and E, and chemicals such as coenzyme Q10 may be able to help repair or mop up damage caused by infrared A. “This is the subject of ongoing research. The main problem is that there’s no regulation of ingredients or equivalent to the SPF system of ratings.”
While suncream companies include antioxidants in their creams, in Britain only a few brands offer specific protection against infrared A – these include Ladival and Eriis.
Some British dermatologists say more research is needed before it can be said that specific protection against infrared A is needed. A spokesman for the British Association of Dermatologists said more evidence was needed on infrared A before it could consider changing its advice on effective sun protection.
Fiona Osgun, health information officer at Cancer Research UK, says: “There’s no good evidence that infrared light causes skin cancer.” Dr Bav Shergill, a consultant dermatologist at Queen Victoria Hospital, East Grinstead, West Sussex, and a member of the British Association of Dermatologists’ skin cancer committee, is cautious, too. He says infrared A does appear to be linked to ‘a cascade of reactions within the skin’, including breakdown of collagen, but adds: “It’s too early to say whether this is clinically relevant. I am open to infrared A having a cosmetic effect on the skin, though.”