One a day or Mother Nature's Way
New evidence shows that vitamin and mineral supplements just can’t compete with the nutrients from Mother Nature.
Americans want to believe in vitamin and mineral pills. We spent an estimated $10 billion on them in 2008, according to the Nutrition Business Journal. But recent studies undertaken to assess their benefits have delivered a flurry of disappointing results. The supplements failed to prevent Alzheimer’s disease, cancer, heart attacks, strokes, type 2 diabetes, and premature death.
“We have yet to see well-conducted research that categorically supports the use of vitamin and mineral supplements,” says Linda Van Horn, Ph.D., a professor of preventative medicine at Northwestern University’s Feinberg School of Medicine in Chicago. “Most studies show no benefit, or actual harm.”
THE POWER OF FOOD:
While some people may need supplements at certain stages of their lives, nutritional deficiencies are uncommon in the U.S. “Almost all of us get or can get the vitamins and minerals we need from our diet,” says Paul M. Coates, Ph.D., director of the Office of Dietary Supplements at the National Institute of Health (NIH).
Major health organizations for cancer, diabetes, and heart disease all advise against supplements in favor of a healthful diet rich in fruits, vegetables, whole grains, and legumes. Unlike pills, those foods-contain fiber plus thousands of health protective substances that seem to work together more powerfully than any single ingredient can work alone. “That’s why it’s dangerous to say, “ I know I don’t eat well, but if I pop my vitamins, I’m covered,” says Karen Collins, R.D, . that you are not covered.”
TOO MUCH CAN HARM :
Another concern is that some vitamin pills can be toxic if taken in high doses for a long time. Studies show that beta-carotene pills, for example, can increase the risk of lung cancer in smokers, and a 2008 review suggests that the pills, plus supplemental doses of vitamin A and e, may increase the risk of premature death. In addition, a government survey found that more than 11 percent of adults take at least 400 international units of vitamin E a day, a dose that has been linked to heart failure, strokes, and an increased risk of death.
People are also apt to combine vitamin tablets and fortified foods, which can cause problems. For instance, too much folic acid---added to wheat products in this country---can mask vitamin B12 deficiency. Untreated, that can lead to irreversible nerve damage. In addition, high doses of folic acid may be associated with an increased risk of precancerous polyps, according to a trial of some 1,000 people at risk for them. “We’re getting several alarming signals that more may not be better,” says Susan T. Mayne, Ph.D., a professor of epidemiology at the Yale School of Public Health.
SUPPLEMENTS STRIKE OUT :
There is insufficient evidence to support the use of supplements to prevent the following conditions:
CANCER: Two large trials published in 2009 came up empty. In one, sponsored by the National Cancer Institute, researchers reported that Vitamin E and the mineral selenium failed to prevent prostate cancer. In fact, researchers noted possible increased risks of prostate cancer from vitamin E, and type 2 diabetes from selenium. The second study, the Physician’s Health Study II, found that neither vitamin C nor E reduced the risk of colon, lung, prostate, or other cancers in men. And women haven’t fared much better: Folic acid and certain other B vitamins provided no protection against breast or any other cancer in one study, and calcium and vitamin D had no effect on breast-cancer risk in another.
Some research suggests that vitamin and mineral supplements may pose particular risks to people who are being treated for cancer. While many cancer patients take antioxidant supplements such as vitamins C, E, and beta-carotene with the hope of reducing the toxicity of chemotherapy and radiation, a 2008 review found that the practice may protect cancer cells as well as normal ones. As a result, many oncologists now advise patients not to use antioxidant pills during those treatments.
HEART DISEASE: Folic acid and other B vitamins failed to prevent heart attacks, strokes, and death from cardiovascular disease in women at risk for heart disease in a 2008 trial by the Harvard Medical School. And neither vitamin C nor E prevented those events in men in the Physicians’ Health Study II. Vitamin E, however, was linked to an increased risk of hemorrhagic stroke.
Antioxidant supplements were previously thought to prevent fatty buildups in arteries, but research now suggests that they may worsen cholesterol levels and blunt the effects of cholesterol lowering drugs. A 2009 review found that diets rich in those vitamins protected people from heart disease but supplements of them did not, underscoring the power of a healthy diet.
Type 2 Diabetes: In a 2009 trial, vitamin and mineral pills didn’t reduce the risk of metabolic syndrome---a cluster of symptoms including abdominal obesity and high levels of LDL (bad) cholesterol and blood sugar---that can lead to type 2 diabetes. Additional 2009 studies found that vitamin pills didn’t prevent type 2 diabetes and might undermine the ability of exercise to improve blood sugar levels. And while many people with diabetes take supplements of the mineral chromium to control blood sugar and lose weight, that benefit is unproven.
Cognitive decline: B vitamins didn’t slow Alzheimer’s disease, and vitamin E failed to prevent dementia in people with cognitive impairment, according to trials from the Alzheimer’s Disease Cooperative Study, and NIH-funded consortium. Another study suggested that high doses of vitamin E slowed down the progression of moderate dementia, but most specialists are wary because of the potential risks, says Paul Aisen, M. D., director of the consortium.
On the other hand, a deficiency of vitamin B12 or thyroid hormone can cause cognitive impairment, so if you’re declining more than normal for your age, you should be tested for those conditions. “But speak to your physician,” Aisen says. “You can’t necessarily replenish low B12 stores on your own.”
Immune Function: The evidence on whether vitamin and mineral supplements can enhance immunity is contradictory, especially for people who eat adequately. And while supplements can boost immune response in older people with nutritional deficiencies, it’s still not known if that results in fewer infections. “In the vast majority of people taking megadoses is not recommended, and may be harmful,” says Kevin High, M.D., chief of infectious diseases at Wake Forest University School of Medicine in Winston-Salem, N. C. An excess of vitamin E, for instance, can backfire.
Glimmers of Hope: Some evidence supports the use of supplements for these conditions:
Eye Disease: People who have at least moderate age-related macular degeneration (AMD), a leading cause of blindness, may be able to limit further damage by taking a daily supplement that contains vitamins C, e, and beta-carotene. But talk with you ophthalmologist first, since the formula could be risky for some people.
Recent research suggests that folic acid and other B vitamins reduce the risk of developing AMD for some people. “This is the first suggestion of a way of preventing early stages of AMD other than avoiding smoking,” says William G. Christen, Sc.D., an associate professor at Brigham and Women’s Hospital in Boston. But the study, sponsored by the National Eye Institute, needs to be repeated before firm recommendations can be made.
Osteoporosis: In a recent comprehensive review of 167 studies, the federal Agency for Healthcare Research and Quality found that calcium and vitamin D pills reduced fractures and bone loss---although the fracture benefit was primarily only in female nursing-home residents. Vitamin D alone also helped prevent falls in older people in a 2009 analysis, but only at doses of 700 IU a day or higher.
Shortfalls of vitamin D are common, recent research suggests, so if you have health problems possibly linked to abnormal calcium metabolism or vitamin D deficiency such as hyperthyroidism and osteoporosis, consider having your blood levels tested. If your reading is low, your doctor will probably prescribe a higher dose vitamin D supplement for a few months, and then retest.
Americans want to believe in vitamin and mineral pills. We spent an estimated $10 billion on them in 2008, according to the Nutrition Business Journal. But recent studies undertaken to assess their benefits have delivered a flurry of disappointing results. The supplements failed to prevent Alzheimer’s disease, cancer, heart attacks, strokes, type 2 diabetes, and premature death.
“We have yet to see well-conducted research that categorically supports the use of vitamin and mineral supplements,” says Linda Van Horn, Ph.D., a professor of preventative medicine at Northwestern University’s Feinberg School of Medicine in Chicago. “Most studies show no benefit, or actual harm.”
THE POWER OF FOOD:
While some people may need supplements at certain stages of their lives, nutritional deficiencies are uncommon in the U.S. “Almost all of us get or can get the vitamins and minerals we need from our diet,” says Paul M. Coates, Ph.D., director of the Office of Dietary Supplements at the National Institute of Health (NIH).
Major health organizations for cancer, diabetes, and heart disease all advise against supplements in favor of a healthful diet rich in fruits, vegetables, whole grains, and legumes. Unlike pills, those foods-contain fiber plus thousands of health protective substances that seem to work together more powerfully than any single ingredient can work alone. “That’s why it’s dangerous to say, “ I know I don’t eat well, but if I pop my vitamins, I’m covered,” says Karen Collins, R.D, . that you are not covered.”
TOO MUCH CAN HARM :
Another concern is that some vitamin pills can be toxic if taken in high doses for a long time. Studies show that beta-carotene pills, for example, can increase the risk of lung cancer in smokers, and a 2008 review suggests that the pills, plus supplemental doses of vitamin A and e, may increase the risk of premature death. In addition, a government survey found that more than 11 percent of adults take at least 400 international units of vitamin E a day, a dose that has been linked to heart failure, strokes, and an increased risk of death.
People are also apt to combine vitamin tablets and fortified foods, which can cause problems. For instance, too much folic acid---added to wheat products in this country---can mask vitamin B12 deficiency. Untreated, that can lead to irreversible nerve damage. In addition, high doses of folic acid may be associated with an increased risk of precancerous polyps, according to a trial of some 1,000 people at risk for them. “We’re getting several alarming signals that more may not be better,” says Susan T. Mayne, Ph.D., a professor of epidemiology at the Yale School of Public Health.
SUPPLEMENTS STRIKE OUT :
There is insufficient evidence to support the use of supplements to prevent the following conditions:
CANCER: Two large trials published in 2009 came up empty. In one, sponsored by the National Cancer Institute, researchers reported that Vitamin E and the mineral selenium failed to prevent prostate cancer. In fact, researchers noted possible increased risks of prostate cancer from vitamin E, and type 2 diabetes from selenium. The second study, the Physician’s Health Study II, found that neither vitamin C nor E reduced the risk of colon, lung, prostate, or other cancers in men. And women haven’t fared much better: Folic acid and certain other B vitamins provided no protection against breast or any other cancer in one study, and calcium and vitamin D had no effect on breast-cancer risk in another.
Some research suggests that vitamin and mineral supplements may pose particular risks to people who are being treated for cancer. While many cancer patients take antioxidant supplements such as vitamins C, E, and beta-carotene with the hope of reducing the toxicity of chemotherapy and radiation, a 2008 review found that the practice may protect cancer cells as well as normal ones. As a result, many oncologists now advise patients not to use antioxidant pills during those treatments.
HEART DISEASE: Folic acid and other B vitamins failed to prevent heart attacks, strokes, and death from cardiovascular disease in women at risk for heart disease in a 2008 trial by the Harvard Medical School. And neither vitamin C nor E prevented those events in men in the Physicians’ Health Study II. Vitamin E, however, was linked to an increased risk of hemorrhagic stroke.
Antioxidant supplements were previously thought to prevent fatty buildups in arteries, but research now suggests that they may worsen cholesterol levels and blunt the effects of cholesterol lowering drugs. A 2009 review found that diets rich in those vitamins protected people from heart disease but supplements of them did not, underscoring the power of a healthy diet.
Type 2 Diabetes: In a 2009 trial, vitamin and mineral pills didn’t reduce the risk of metabolic syndrome---a cluster of symptoms including abdominal obesity and high levels of LDL (bad) cholesterol and blood sugar---that can lead to type 2 diabetes. Additional 2009 studies found that vitamin pills didn’t prevent type 2 diabetes and might undermine the ability of exercise to improve blood sugar levels. And while many people with diabetes take supplements of the mineral chromium to control blood sugar and lose weight, that benefit is unproven.
Cognitive decline: B vitamins didn’t slow Alzheimer’s disease, and vitamin E failed to prevent dementia in people with cognitive impairment, according to trials from the Alzheimer’s Disease Cooperative Study, and NIH-funded consortium. Another study suggested that high doses of vitamin E slowed down the progression of moderate dementia, but most specialists are wary because of the potential risks, says Paul Aisen, M. D., director of the consortium.
On the other hand, a deficiency of vitamin B12 or thyroid hormone can cause cognitive impairment, so if you’re declining more than normal for your age, you should be tested for those conditions. “But speak to your physician,” Aisen says. “You can’t necessarily replenish low B12 stores on your own.”
Immune Function: The evidence on whether vitamin and mineral supplements can enhance immunity is contradictory, especially for people who eat adequately. And while supplements can boost immune response in older people with nutritional deficiencies, it’s still not known if that results in fewer infections. “In the vast majority of people taking megadoses is not recommended, and may be harmful,” says Kevin High, M.D., chief of infectious diseases at Wake Forest University School of Medicine in Winston-Salem, N. C. An excess of vitamin E, for instance, can backfire.
Glimmers of Hope: Some evidence supports the use of supplements for these conditions:
Eye Disease: People who have at least moderate age-related macular degeneration (AMD), a leading cause of blindness, may be able to limit further damage by taking a daily supplement that contains vitamins C, e, and beta-carotene. But talk with you ophthalmologist first, since the formula could be risky for some people.
Recent research suggests that folic acid and other B vitamins reduce the risk of developing AMD for some people. “This is the first suggestion of a way of preventing early stages of AMD other than avoiding smoking,” says William G. Christen, Sc.D., an associate professor at Brigham and Women’s Hospital in Boston. But the study, sponsored by the National Eye Institute, needs to be repeated before firm recommendations can be made.
Osteoporosis: In a recent comprehensive review of 167 studies, the federal Agency for Healthcare Research and Quality found that calcium and vitamin D pills reduced fractures and bone loss---although the fracture benefit was primarily only in female nursing-home residents. Vitamin D alone also helped prevent falls in older people in a 2009 analysis, but only at doses of 700 IU a day or higher.
Shortfalls of vitamin D are common, recent research suggests, so if you have health problems possibly linked to abnormal calcium metabolism or vitamin D deficiency such as hyperthyroidism and osteoporosis, consider having your blood levels tested. If your reading is low, your doctor will probably prescribe a higher dose vitamin D supplement for a few months, and then retest.
posted by Stan Kent at
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