Vitamins may not reduce cancer, heart disease: Report

Wshington, July 12: Vitamin supplements may not prevent cancer or heart disease an influential US government advisory panel has said.
In a report appearing in the 'Annals of Internal Medicine 2003', the US Preventive Services Task Force said even carotene supplementation could do more harm than good to patients suffering from lung cancer.


Researchers at the Oregon Health and Science University also endorsed this view.



The task force researched medical reports from 1966 to 2001, including randomized controlled trials, cohort studies, and metaanalyses of trials that examined the role of Vitamins A, C, E and B-Carotene, multi-vitamins containing folic acid and antioxidant combinations.



Overall, 932 citations were reviewed. Of these, 102 were reports from 36 randomized-controlled trials. Ten trials were of sufficient quality for their findings to be included in the recommendations, the task force opined.

The panel admitted that only vitamin supplements were reviewed for their role in the prevention of cardiovascular diseases. The source of the vitamins in food and their role in cancer and cardiovascular death and disease was not evaluated, they added.


They also did not address the role of vitamin supplementation in people with potential nutritional deficiencies, including pregnant and lactating women, children, elderly people, and people with chronic illnesses.


The researchers, however, did evaluate vitamin supplementation to the development or prevention of breast, prostate, lung, and colon-related tumours and to non-melanoma skin cancer.

The review failed to discover studies on benefits of taking vitamins A or C for maintaining cardiovascular health or for reducing risk of cancer.


Data on multi-vitamins and antioxidants were mixed. Folic acid supplementation did seem to reduce the risk of colon cancer in several studies, but the relation needed to be confirmed by prospective studies, the task force said.



Vitamin E was found to be useful in reducing cardiovascular disease mortality in the nurses' and the physician's health studies.



"With the exception of Vitamins for which there is compelling evidence of net harm (for example, beta carotene supplementation in smokers), there is little reason to discourage people from taking vitamin supplements."

"Patients should be reminded that taking vitamins does not replace the need to eat a healthy diet," the researchers concluded.

Bureau Report