There is no evidence that taking antioxidant supplements such as vitamin A and E prolongs life - and some may even hasten death, new research suggests.

A review of 67 studies involving more than 230,000 people found "no convincing evidence" that antioxidant supplements help people to live longer.

Instead, experts warned that vitamins A and E and beta-carotene appeared to increase mortality.

The review, published today by the Cochrane Collaboration, an independent non-profit research organisation, is based on trials of five antioxidants.

Goran Bjelakovic, who carried out the review at Copenhagen University Hospital in Denmark, said: "We could find no evidence to support taking antioxidant supplements to reduce the risk of dying earlier in healthy people or patients with various diseases.

"The findings show that if anything, people given the antioxidants beta-carotene, vitamin A and vitamin E showed increased rates of mortality. Evidence does not support the use of antioxidant supplements in the general healthy population or in patients with certain diseases."

But Patrick Holford, a nutritionist who has formulated some supplements for the firm BioCare, branded the review a "stitch-up".

He said: "Antioxidants are not meant to be magic bullets and should not be expected to undo a lifetime of unhealthy habits.

"But when used properly, in combination with eating a healthy diet, getting plenty of exercise and not smoking, antioxidant supplements can play an important role in maintaining overall health."