I had no idea fresh oj was over a year old.
I should not be shocked but i was blown away.
This country is nuts. No labels telling you were
food is specifically produced.
tell Gersh-g-
Americans love supplements, but there is no evidence the pills make most of us any healthier
By Elizabeth Cooney, Globe Correspondent | February 23, 2009
Every day, half of America downs a multivitamin, and feels better for it. Never mind a multitude of research showing that vitamin supplements provide no proven health benefit for most people.
The same people who routinely take vitamin pills - health-conscious consumers who already have a good diet - are least likely to need them, researchers say. That holds true for children, too, a recent survey found.
"As Americans, we seem to sometimes perceive, or maybe misperceive, that more is always better," said Patsy Brannon, a professor of nutritional sciences at Cornell University. "But that's not always the case."
Now, there is fresh evidence for that view.
A Women's Health Initiative trial, part of a massive national study best known for finding risks in hormone therapy, tracked multivitamin use in more than 161,000 postmenopausal women. After eight years, it found that taking multivitamins made no difference in whether women developed cancer or cardiovascular disease.
The findings are consistent with other recent studies showing that calcium and vitamin D had no influence on women's risk of breast cancer, and vitamin E, vitamin C, and selenium did not affect men's risk of prostate or other cancers.
In other words, consumers' money might be better spent on fruits, vegetables, whole grains, fish, low-fat dairy, and legumes that constitute a healthy diet.
"People should strive to get an adequate intake of nutrients, including vitamins and minerals, from food rather than supplements," said Dr. JoAnn E. Manson, chief of preventive medicine at Brigham and Women's Hospital, and a principal investigator in the study. Taking vitamin pills may be a good "insurance policy" for people who have bad diets, she said, but hold little value for the rest of us.
People worried about giving up their vitamins can take comfort in the trend toward food fortification. Today's orange juice contains calcium and vitamin D, and even Coke and Pepsi have jumped on the functional food bandwagon, offering versions with vitamins and minerals. Folic acid has been added to the food supply since 1996.
The nation's vitamin pill habit springs not just from a desire for enhanced vitality in everyday life, but protection aganist chronic diseases.
Evidence of a connection between vitamins and a reduced risk of certain diseases began appearing in the 1990s. Multivitamin studies reported in 2001 and 2003 hinted at a reduced risk of colorectal cancer, but only if they were taken for at least 10 years.
But more rigorous randomized clinical trials have failed to confirm these findings, or have not been done in some cases, leading a group convened by the National Institutes of Health in 2006 to say there was insufficient clinical evidence to recommend multivitamins.
Some research even demonstrated possible harm from taking vitamin supplements. Megadoses of beta carotene, for example, increased the risk of lung cancer in people who smoked or worked in the asbestos industry. Vitamin D and calcium can up the risk of kidney stones in some people. A Chinese study reported higher rates of esophageal cancer in long-term users of selenium, beta-carotene, and vitamin E.
Vitamin D is getting attention now, with intriguing suggestions about cancer, diabetes, and multiple sclerosis. Most Americans, especially in the northern part of the country, don't get enough of the sunshine vitamin through exposure to sunlight or from their diets.
"Vitamin D is looking very promising, but it may require doses higher than are typically found in the traditional multivitamin," said Manson of Brigham and Women's, who is awaiting funding for a large randomized clinical trial of vitamin D benefits.
While the jury is out, multivitamins - which can cost consumers as much as $50 a month for the more complicated formulas - may help people with limited food intake. Men eating fewer than 1,500 calories a day or women eating fewer than 1,250 calories might find it otherwise difficult to get all the nutrients they need.
Women of childbearing age should take folic acid to prevent birth defects, and women with heavy menstrual cycles may benefit from iron supplements. Older people can preserve bone strength by taking additional calcium and vitamin D.
But the rest of us may already be getting more vitamins than we need, or should have.
Brannon, the Cornell University professor, who served on the NIH multivitamin panel, suggests that if someone is going to take vitamins, they should choose pills that offer no more than 100 percent of the government's Recommended Daily Allowance; many vitamins offer several times that amount. She also recommends moderation in eating fortified foods.
"It's an area we don't have a good handle on," said Alice Lichtenstein, professor of nutrition science and policy at Tufts University. "There's no overall monitoring of all the different types of food and what's fortified and who's choosing them. We may be getting to the point where we may be consuming more than we actually should."
The debate over vitamins shows no sign of slowing down.
The Women's Health Initiative study, while a valuable contribution, is not the final word, specialists caution.
"There may still be benefits of multiple vitamins that were not seen in this recent report because the study was relatively short," Walter Willett, chairman of nutrition at Harvard School of Public Health, said of the study. "Conditions like cancers, heart disease, and dementia develop over decades, not just a few years."
It was an observational study, meaning scientists watched what happened to women who chose to take multivitamins and compared them to women who didn't. Observational studies can hint at cause and effect, but more rigorous clinical trials, in which people are randomly assigned to take multivitamins or not, would carry more weight.
For now, researchers are eager for the results of one of the next big vitamin studies in the pipeline. The Physicians Health Study II, a Harvard-led randomized clinical trial of multivitamins in men over 50, will release its findings in 2012.
Elizabeth Cooney can be reached at lizcooney@gmail.com. |
