A trace mineral found in everyday foods could be the key to keeping cancer at bay.

Adding extra selenium – which is in Brazil nuts, bread, cereals, fish, poultry and meat – to the diet has already been proved to help cancer survivors by halving their risk of contracting the disease again.

Now British scientists are launching a trial to discover if taking a daily supplement of the mineral could prevent healthy people developing the disease.

Since the Sixties it has been thought that selenium supplements might prevent dietary-linked cancers.

This is because some areas, where people have a naturally high intake of the mineral, have lower than expected rates of the disease.

The most promising evidence so far comes from a U.S. study which showed an overall drop of 50 per cent in cancer deaths and a fall of 37% in new cases – especially lung, bowel and prostrate – among 1,300 volunteers taking supplements for four years.

But the small-scale research involved people who had suffered skin cancer and there are still doubts over whether it could help healthy people.

This has led to the launch by the Cancer Research Campaign, supported by the supermarket chain Asda, of the most ambitious study ever to investigate the trace element’s cancer blocking potential.

Altogether 40,000 people from the U.S., Britain and three other European countries will take part in the study, which will start here as a pilot project involving 500volunteers.

Britain has been chosen because of low levels of selenium consumption. The average intake of 34 micrograms a day is only half the amount found in the diet 25 years ago. It is also less than half the 75 mcg a day recommended for men and lower than the 80 mcg recommended for women.

Dr, Margaret Rayman, of Surrey University Guildford, who is organising the study in Britain said “Selenium intakes have been falling for several years and thee is no sign of a change in the trend.

One of the key reasons is a major reduction over the last 20 years in the use of North American wheat, which contains high levels of selenium.

The pilot study will use GP surgeries in Guisborough, Cleveland; Bungay, Suffolk; and Bromsgrove, Worcestershire, to recruit volunteers aged between 60 and 74.

“The trial aims to show not only whether selenium has a protective effect against cancer, but also how much selenium is needed to have this effect and which people will benefit most” said Dr Rayman.

Cancer Research Campaign director general Professor Gordon McVie said “If this study is successful, it will be the first time in the UK that a nutritional supplement has been conclusively shown to have beneficial health qualities.

Dieticians say assessing dietary intake through foods is difficult as selenium differs from most other nutrients by varying hugely in food stuffs – you can never by sure how much you are getting. Doctors assess levels by analysing toe clippings and taking blood.

Too much selenium is toxic and consumers are advised to keep intake well below the toxic level of 800mcg a day.



Home Up

Send mail to with questions or comments about this web site.
Copyright 2005 Honil Limited
Last modified: December 18, 2005