Multivitamins failed in preventing cardiovascular disease or cancer in postmenopausal women, according to a new study. The study published in the February issue of The Archives of Internal Medicine adds to other studies that have shown that various antioxidant supplements do not prevent cancer of any kind.
For the study, the researchers analyzed medical data from 161,800 postmenopausal women from two Women's Health Initiative trials for a period of eight years. About four women in 10 said they took multivitamins. Almost 40 percent of them took multivitamins for a period of 15 years.
After adjusting for factors such as age, physical activity, family history of cancer, the researchers found no beneficial effect from multivitamin use on the risk of breast cancer, colorectal cancer, endometrial cancer, lung cancer, ovarian cancer, heart attack, stroke, or blood clots.
Many studies have shown that people who eat a healthy diet, rich in fruits and vegetables, are less prone to develop the deadly disease. Fruits and vegetables are rich in these antioxidants and it has been shown that these vitamins offer protection against damage caused by free radicals, which can harm cells, tissues and organs. Experts say that whole foods are better than dietary supplements.
But this benefit of lowering cancer risk doesn’t apply to supplements. Although this study looked only at postmenopausal women, the findings “are consistent with most previously published results,” the researchers note.
An earlier study (of a much smaller group) conducted on the effect of selenium supplementation on the recurrence of skin cancers did not demonstrate a reduced rate of recurrence of skin cancers, but did show a reduced occurrence of total cancers.
“Multivitamins, like all other dietary supplements, are meant to be used as part of an overall healthy lifestyle; they are not intended to be magic bullets that will assure the prevention of chronic diseases like cancer,” Andrew Shao, a vice president at the Council for Responsible Nutrition, a trade group, was quoted as saying.
At the same time, doctors say that cancer and heart disease are conditions with multiple causes (genetics, smoking, obesity, diet) and taking a multivitamin doesn’t replace a diet lacking in nutrients.
On the other hand, multivitamins could prove to be helpful for someone who has a busy lifestyle and skips meals, as multivitamins are considered a valid way to supplementing the diet.
It appears that those with healthier nutrition, more active lifestyles and greater food security tend to use vitamin and mineral supplements, while those who really need them don’t take them. In a recent study, researchers at the University of California reached the conclusion that teenagers and children who confronted with the greatest risk of nutritional deficiencies were the least likely to eat enough fruits and vegetables or to take vitamins from their diet.
