english.prescrire.org > Spotlight > Archives : 2005 > Antioxidants: ineffective in preventing cancer and cardiovascular disease

Spotlight: Archives

Every month, the subjects in Prescrire’s Spotlight.

2005 : 1 | 30 | 60

Antioxidants: ineffective in preventing cancer
and cardiovascular disease

"Antioxidant" treatments have no proven effectiveness against cancer or cardiovascular disease. There is no justification for their routine use in a population that enjoys a varied diet.

Substances that have a highly sensitive chemical reaction, known as "free radicals", appear to be implicated in various diseases. There is a theory that some substances, called antioxidants, supposedly act on the free radicals and prevent disease. Several trials have been carried out to evaluate the possible effectiveness of using antioxidants to prevent cancer and cardiovascular disease.

The Su.vi.max trial evaluated the effect of these substances. This trial was organised by the French public health authorities with the support of food and pharmaceuticals manufacturers. More than 13,000 adults were given either a placebo or a capsule containing selenium, zinc and vitamins A, C and E. After 7½ years of monitoring, the treatment was not shown to have any significant impact on the overall death rate, nor on the number of new cases of cancer, or cardiovascular pathologies.

These unfavourable findings corroborate other recent and equally negative results from large-scale trials (several hundred thousand patients). They all conclude that antioxidants fail to demonstrate any preventive effect against cancer and cardiovascular disease, and appear to have no positive impact on the mortality rate.

©Prescrire May 2005

Source: "Pas d’effet préventif des antioxydants" Rev Prescrire 2005 ; 25 (261) : 376-377.

- More articles in Prescrire's "Spotlight"...