- Wearing sunscreen makes people stay in the sun too long
- and could release cancer-causing substances into the body, according
- A study, published in the US Journal of the National
Cancer Institute, said that people who wore higher factor sunscreens tended
to stay out much longer, because they felt protected from the risk of sunburn.
- And a British biochemist has suggested that the cocktail
of chemicals involved in sunscreens could be converted into "free
radical" molecules, which could cause cell damage and lead to cancer.
- The US study, revealed on the BBC's Newsnight programme,
appears to demonstrate why incidence of skin cancer has increased, even
though sunscreens have become popular among fair-skinned people.
- Spreading confusion
- The Health Education Authority has accused the study's
authors of spreading a confusing message.
- A spokesman said: "Don't stop using sunscreens but
do remember that you shouldn't use them so you can sunbathe longer."
- Dr Philippe Autier, a scientist at the European Institute
of Oncology in Milan, led the original study.
- He found children using sunscreen returned from holiday
with more skin moles - a possible sign of increased cancer risk.
- He set out to see if this was because sunscreens were
making sunbathers overconfident.
- He gave two groups of volunteers different strengths
of sunscreen, and found that those using less protective sunscreen spent
25% less time in the sun than those with high-protection creams.
- He said: "Consumers should be warned that using
a sunscreen may increase the amount of time spent in the sun.
- "Because of that it may increase your risk of sun
- Meanwhile, Dr John Knowland, a biochemist at Oxford University,
is looking at another reason why sunscreen may be behind increased skin
- He said: "The important thing to remember is that
a sunscreen that absorbs energy cannot actually destroy that energy, it
has to do something with it.
- "The concern that some people have is that they
can convert the light energy into chemical energy, which is potentially
- He and his colleagues are trying to model the effects
of sunlight on human skin, looking at how the DNA might be changed.
- Experts advise sunscreen use
- Professor Jack Cuzick, head of the epidemiology unit
at the Imperial Cancer Research Fund, said: "Obviously people would
be more at risk if they didn't wear any sunscreen but they should not rely
solely on sunscreen to protect themselves against the sun.
- "If they do use a sunscreen they should make sure
it has both UVA and UVB protection.
- "This research does not change our advice that the
best way to protect against skin cancer is to cover up and moderate your
exposure to the sun."