Adding to a growing scientific consensus, a large Danish study released Tuesday found that vitamin E and other antioxidant supplements provide no health benefits and may even produce a small increase in the risk of death.

The report in the Journal of the American Medical Association immediately was criticized by vitamin makers and some researchers, but its findings are similar to other studies suggesting that supplements are not as quick and easy a way to improve health as their promoters claim.

Supplements “have great biological plausibility, and we all wish that they would work,” but they do not, said Dr. Edgar R. Miller of Johns Hopkins University, who was not involved in the new study.

“We need to concentrate on lifestyle modifications, stop smoking, and lose weight, and not be deceived into thinking that taking a supplement will lower the risk of mortality,” he said.

Dr. Goran Bjelakovic of Copenhagen University Hospital and his colleagues performed what is known as a meta-analysis, combining the results from 68 previously published clinical trials involving nearly 250,000 patients.