Older Americans are hooked on
vitamins
despite scarce evidence they work
source:April
6, 2018 by Liz Szabo, Kaiser Health News
There's no conclusive evidence that dietary
supplements prevent chronic disease.
There’s no solid evidence that taking multi- or any other kind of vitamin is
beneficial to your health unless
you’re vitamin-deficient:- |
|
July 2019: Vast
majority of dietary supplements don't improve heart health or put off death,
study of studies finds (antioxidants,
ß-carotene,
vitamin B-complex, multivitamins, selenium, vitamin A, vitamin B3/niacin,
vitamin B6, vitamin C, vitamin E, vitamin D alone, calcium alone, calcium
and vitamin D together, folic acid, iron and omega-3 fatty acid (fish oil).)
quack_watch_portal.htm
May 2018: Multivitamins, vitamin D, calcium and
vitamin C, — the most common supplements, — showed no advantage in the
prevention of cardiovascular disease, heart attack, stroke or premature
death.
The multivitamins included A, B1, B2, B3 (niacin), B6, B9 (folic acid), C, D
and E; and ß-carotene; calcium; iron; zinc; magnesium; and selenium.
It's most beneficial to rely on a healthy diet to get your fill of vitamins
and minerals," Dr. Jenkins said
From a systematic review of existing data and single randomized control
trials published from 2012 to 2017. |
- Rigorous studies have failed to show
that fish oil supplements prevent heart attacks.
Fish Oil Pills Don't Prevent Heart Attacks, a
Study of Studies Finds
- Neither vitamin E nor
folic acid supplements did anything to protect the heart. Even worse, studies linked high-dose
vitamin E to a higher risk of
heart failure, prostate cancer and death from any cause.
Vitamin E, also an antioxidant, increased the risk of prostate cancer in men
- folic acid pills had no overall benefit for heart disease
- beta carotene pills actually increased lung cancer rates
- calcium supplement doesn't
protect against bone fractures but increase the risk of kidney stones and
heart disease.
- The "90+ Study"
on AGING -- Anti-Oxidants & some
Vitamins DON'T make you live longer, including
E, A, C & Calcium
-
If you're taking vitamin D you're probably
taking too much.
Food is Better Than Supplements for Increasing
Longevity, New Study Shows
When it comes to a longer lifespan, a healthy diet works
better than pills --- By Trisha Calvo April 08,
2019
A new
Tufts University study involving more than 27,000 Americans is the latest
research to show that most supplements may not do much to improve health—or at
least can’t compete with the benefits of a healthy diet. The researchers found
that taking supplements didn’t lower the risk of death during the study
follow-up period, while those who got the recommended amount of certain
nutrients from foods had a lower risk of death in that time frame.
“These results are consistent with current dietary recommendations,” says study
author Fang Fang Zhang, M.D., Ph.D., associate professor in the Friedman School
of Nutrition Science and Policy at Tufts University. “The general U.S.
population should aim to get adequate nutrition from healthy foods, and a
healthy diet.”
What the Study Found
The researchers analyzed National
Health and Nutrition Examination Survey (NHANES) data on supplements such
as multivitamins, vitamin C, and
calcium—which the study participants took—along
with info on the foods they ate. Taking supplements, the study authors found,
didn’t translate to a lower risk of death from cardiovascular disease, cancer,
or any cause for that matter. Getting adequate amounts of
vitamin K and magnesium from food, however,
reduced the risk of dying overall by more than 20 percent. And those whose diet
had enough of vitamins A and
K, copper, and zinc cut the risk of death
from cardiovascular disease by half.
When the researchers analyzed the data, they found that in supplement takers,
nutrients from the foods they ate were protective, but nutrients from the
supplements were not. In fact, they didn’t need supplements at all to meet their
daily requirements for vitamins and
minerals.
The study also highlighted the negative effects of overuse of supplements: For
example, getting 1,000 mg per day of calcium in
pill form was linked to a 62 percent increased risk of cancer. However, when
people got that much calcium from food, it didn’t
increase cancer risk, Zhang says.
Stephen Fortmann, M.D., senior director of science programs at the Kaiser
Permanente Center for Health Research, who worked on a systematic review of
supplements for the U.S. Preventive Services Task Force in 2013, says the
results from this new study are in line with the findings from that report.
“There’s not a lot of evidence that these supplements do any good.”
When Are Supplements Needed?
More than half of American adults take
multivitamins or another supplement, according to
the NHANES data, perhaps in part because of what
they are—or aren’t—already eating. It’s no secret that many Americans don’t
follow a healthy diet; for example, about 90 percent of people don’t eat the
daily recommended 1½ to 2 cups of fruit and 2 to 3 cups of vegetables, according
to the Centers for Disease Control and Prevention.
But can supplements make up for those shortfalls? Supplement proponents argue
that it can be challenging for Americans to stick to dietary guidelines. “The
majority of U.S. adults do not get the recommended amount of nutrients," says
Andrew Shao, interim senior vice president for scientific and regulatory affairs
at the Center for Responsible Nutrition (CRN), a
trade association for the supplement industry. “It is a health benefit to get
the nutrients you need.”
Still, experts say that eating healthfully is a preferred way to stay healthy.
“Using dietary supplements shouldn’t be a substitute for a healthy, balanced
diet,” Zhang says. What’s more, when you get nutrients from food, you are also
getting a variety of other compounds, such as
phytochemicals, that interact with one another in myriad ways, some of
which scientists may not even understand yet.
“It’s possible that these particular benefits we’ve seen here could reflect the
complex interaction among multiple nutrients from food,” Zhang says. “We don’t
eat isolated nutrients.”
Another concern with supplements is that the Food and Drug
Administration classifies them differently from drugs. So the companies
that make and sell them aren’t required to prove that they’re safe for their
intended use, that they work as advertised, or even that their packages contain
what the labels say they do.
There are times when supplements are recommended, such as if a patient is
deficient in a certain nutrient due to a health issue, Zhang says. In some
cases, a doctor might also suggest taking prescription supplements, which are
subject to FDA regulations for drugs.
People who may need supplements include:
Women planning to become pregnant within a month.
Folic acid supplements are recommended to reduce
the risk of brain and spinal-cord abnormalities (called neural tube defects)
that can occur in the first months of pregnancy.
Pregnant women. Folic acid is needed to protect against neural tube defects, and
vitamin D is needed to help prevent pre-eclampsia.
Strict vegans who consume no meat, fish, eggs, or dairy. A daily
vitamin B12 supplement can be recommended;
B12 is found only in animal foods.
People over age 60. At this age, you may need vitamin B12,
because with age, some people lose the ability to absorb vitamin
B12 from food.
A person who rarely gets out in the sun. He/she may need vitamin
D3. Our bodies make vitamin D
from sunlight.
Those taking certain drugs. Vitamin B12 and
magnesium supplements may be needed for people
taking diabetes medication such as metformin (Glucophage and generic) and
long-term users of heartburn drugs, such as lansoprazole (Prevacid and generic)
or famotidine (Pepcid and generic).
Eating a Healthier Diet
One main takeaway from the study, Zhang says, is that if
your diet is made up mostly of nutritious foods, supplements won’t necessarily
offer any additional benefits.
You can get the nutrients highlighted in this study from many foods. For
example, dark green vegetables such as broccoli and kale have vitamins A and K. Butternut
squash, carrots, sweet potatoes, and egg yolks are rich in vitamin
A. Leafy greens, nuts, and whole grains supply
copper and magnesium.
"But it is best not to focus on specific nutrients, but rather trust that a
balanced diet of healthy foods will meet your nutritional needs," says Charlotte
Vallaeys, M.S., Consumer Reports' senior food and nutrition policy analyst.
"When you eat a variety of healthy whole foods—whole grains, fruits and
vegetables, nuts, legumes, and lean meats—you get the vitamins and minerals you
need."
==========================================================================================================
When she was a young physician, Dr.
Martha Gulati noticed that many of her mentors were prescribing
vitamin E and folic acid to patients. Preliminary studies in the
early 1990s had linked both supplements to a lower risk of heart disease.
She urged her father to pop the pills as well: "Dad, you should be on these
vitamins, because every cardiologist is taking them or putting their patients on
(them)," recalled Gulati, now chief of cardiology for the
University of Arizona College of Medicine-Phoenix.
But just a few years later, she found herself reversing course, after
rigorous clinical trials found neither vitamin E nor
folic acid supplements did
anything to protect the heart. Even
worse, studies linked high-dose
vitamin E to a
higher risk of heart failure, prostate
cancer and death from any cause.
"'You might want to stop taking (these),'" Gulati told her father.
More than half of Americans take vitamin supplements,
including 68 percent of those age 65 and older, according to a 2013 Gallup poll.
Among older adults, 29 percent take four or more supplements of any
kind, according to a Journal of Nutrition study published in 2017.
Often, preliminary studies fuel irrational exuberance about a promising
dietary supplement, leading millions of people to buy in to the
trend. Many never stop. They continue even though more rigorous studies—which
can take many years to complete—almost never find that vitamins prevent
disease, and in some cases cause harm.
"The enthusiasm does tend to outpace the evidence," said Dr. JoAnn Manson, chief
of preventive medicine at Boston's Brigham and Women's Hospital.
There's no conclusive evidence
that dietary supplements prevent chronic disease in the average American, Manson said. And while a
handful of vitamin and
mineral studies have had positive
results, those findings haven't been strong enough to recommend supplements to
the general U.S. public, she said.
The National Institutes of Health has spent more than $2.4 billion since 1999
studying vitamins and
minerals. Yet for "all the research
we've done, we don't have much to show for it," said Dr. Barnett Kramer,
director of cancer prevention at the National Cancer Institute.
A big part of the problem, Kramer said, could be that much nutrition research
has been based on faulty assumptions, including the notion that people need
more vitamins and minerals than a typical diet provides; that megadoses are
always safe; and that scientists can boil down the benefits of vegetables like
broccoli into a daily pill.
Vitamin-rich foods can cure diseases related to vitamin deficiency. Oranges and
limes were famously shown to prevent scurvy in vitamin-deprived 18th-century
sailors. And research has long shown that populations that eat a lot of fruits
and vegetables tend to be healthier than others. But when researchers tried to
deliver the key ingredients of a healthy diet in a capsule, Kramer said,
those efforts nearly always failed.
It's possible that the chemicals in the fruits and vegetables on your plate work
together in ways that scientists don't fully understand—and which can't
be replicated in a tablet, said Marjorie McCullough, strategic director of
nutritional epidemiology for the American Cancer Society.
More important, perhaps, is that most Americans get plenty of the essentials,
anyway. Although the Western diet has a lot of problems—too much
sodium, sugar, saturated fat and calories, in general—it's not short on
vitamins, said Alice Lichtenstein, a professor at the Friedman School of
Nutrition Science and Policy at Tufts University.
And although there are more than 90,000 dietary supplements from
which to choose, federal health agencies and advisers still recommend that
Americans meet their nutritional needs with food, especially fruits and
vegetables. Also, American food is highly fortified—with
vitamin D in milk, iodine in salt, B vitamins in flour,
even calcium in some brands of orange juice. Without even
realizing it, someone who eats a typical lunch or breakfast "is essentially
eating a multivitamin," said journalist Catherine Price, author of "Vitamania:
How Vitamins Revolutionized the Way We Think About Food."
That can make studying vitamins even more complicated, Price said. Researchers
may have trouble finding a true control group, with no exposure to supplemental
vitamins. If everyone in a study is consuming fortified food,
vitamins may appear less effective.
The body naturally regulates the levels of many nutrients, such as
vitamin C and many B vitamins, Kramer said, by excreting what it doesn't need
in urine. He added: "It's hard to avoid getting the full range of
vitamins."
Not all experts agree. Dr. Walter Willett, a professor at the Harvard T.H. Chan
School of Public Health, says it's reasonable to take a daily
multivitamin "for insurance." Willett said that clinical trials underestimate
supplements' true benefits because they aren't long enough,
often lasting five to 10 years. It could take decades to notice a lower rate of
cancer or heart disease in vitamin takers, he said.
For Charlsa Bentley, 67, keeping up with the latest nutrition research can be
frustrating. She stopped taking
calcium, for example, after studies
found it doesn't protect against bone
fractures. Additional studies suggest
that calcium supplements increase the risk of kidney stones and heart disease. "I faithfully chewed those
calcium supplements, and then a study said they didn't do any good at
all," said Bentley, from Austin, Texas. "It's hard to know what's effective and
what's not."
Bentley still takes five supplements a day: a multivitamin to
prevent dry eyes, magnesium to prevent cramps while exercising,
red yeast rice to prevent diabetes,
coenzyme Q10 for overall health and
vitamin D based on her doctor's recommendation.
Like many people who take dietary
supplements, Bentley also exercises
regularly—playing tennis three to four times a week—and watches what she eats.
People who take vitamins tend to be healthier, wealthier and
better educated than those who don't, Kramer said. They are probably less
likely to succumb to heart disease or cancer, whether they take
supplements or not. That can skew research results, making
vitamin pills seem more effective than they really are.
Preliminary findings can also lead researchers to the wrong conclusions.
For example, scientists have long observed that people with high levels of an
amino acid called homocysteine are more likely to have heart attacks. Because
folic acid can lower homocysteine levels, researchers once
hoped that folic acid supplements would prevent heart attacks and strokes. In a
series of clinical trials, folic acid pills lowered homocysteine levels but had
no overall benefit for heart disease, Lichtenstein said.
Studies of fish oil
also may have led researchers astray. When
studies of large populations showed that people who eat lots of seafood had
fewer heart attacks, many assumed that the benefits came from the
omega-3 fatty acids in fish oil, Lichtenstein said.
Rigorous studies have failed to
show that fish oil supplements prevent heart attacks. A clinical trial of fish oil pills and
vitamin D, whose results are expected to be released within
the year, may provide clearer questions about whether they prevent disease.
But it's possible the benefits of sardines and salmon have nothing to do with
fish oil, Lichtenstein said. People who have fish for dinner may be
healthier due to what they don't eat, such as meatloaf and cheeseburgers.
"Eating fish is probably a good thing, but we haven't been able to show that
taking fish oil (supplements) does anything for you," said Dr. Steven Nissen,
chairman of cardiovascular medicine at the Cleveland Clinic Foundation.
Taking megadoses of vitamins and minerals, using amounts that people could never
consume through food alone, could be even more problematic. "There's something
appealing about taking a natural product, even if you're taking it in a way that
is totally unnatural," Price said. Early studies, for example, suggested that
beta carotene, a substance found in carrots, might help prevent
cancer.
In the tiny amounts provided by fruits and vegetables,
beta carotene and similar substances appear to protect the body from a process
called oxidation, which damages healthy cells, said Dr. Edgar Miller, a
professor of medicine at Johns Hopkins School of Medicine.
Experts were shocked when two large, well-designed studies in the 1990s found
that beta carotene pills actually increased lung cancer rates.
Likewise, a clinical trial published in
2011 found that vitamin E, also an antioxidant, increased the risk of prostate cancer in men by 17 percent. Such studies reminded
researchers that oxidation isn't all bad; it helps kill bacteria and malignant
cells, wiping them out before they can grow into tumors, Miller said.
"Vitamins are not inert," said Dr. Eric Klein, a prostate
cancer expert at the Cleveland Clinic who led the vitamin E study.
"They are biologically active agents. We have to think of them in the same way
as drugs. If you take too high a dose of them, they cause side effects."
Gulati, the physician in Phoenix, said her early experience with recommending
supplements to her father taught her to be more cautious. She
said she's waiting for the results of large studies—such as the trial of
fish oil and vitamin D—to guide her advice on
vitamins and supplements. "We should be responsible physicians," she said,
"and wait for the data."
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