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Herbs and Vitamins: Sorting out fact from fiction amid a
storm of controversy
(Author Unknown)
"The most powerful nutritional force in the universe, a super-powered,
full-spectrum liquid organic supplement with 72 bioelectrical minerals, 16 vitamins, and
18 amino acids."
You've seen advertisements like these in magazines and health food stores. The hype is
unavoidable white oak helps you live longer, melatonin prevents cancer, magnesium
eases migraines, and essence of flowers can reverse hot flashes.
Since 1994, when Congress changed Food and Drug Administration (FDA) regulation of
"nutritional" supplements, there's been an explosion of
"health-enhancing" megavitamins, magic pills and potions. Almost every mall in
America has a health food store, shelves lined with products that promise to relieve pain,
help you sleep better and give your health, vitality and virility a boost.
It's a $6 billion-a-year business, and it's booming as people search for a fast fix
an easy way to feel better and stay healthy. One-quarter to one-third of Americans
now take daily vitamin supplements. Seventy percent take nutritional supplements at least
occasionally, and one in three people with chronic disease looks to herbal remedies for
help.
Now, more than ever, people are focusing on nutrition to help them remain healthy and
active. That's good. But do you need supplements? Do they work? And perhaps most
important, are they safe?
The answers to these questions are not always clear-cut. There's disagreement, even within
the medical community, as researchers continue to uncover new information about how
nutrition affects your health. Further clouding the issue is an almost daily barrage of
media reports on new studies some suggesting benefits from supplements, others
indicating harm. And then there are those advertisements, promising health in a capsule or
in a steaming herbal brew.
So how do you sort out fact from fiction from outright fantasy amid the swirl of
information about vitamin and nutritional supplements? We hope this essay will help. In
it, we'll discuss what's known about supplements and what's not. We'll talk about who may
need a supplement and who doesn't. And, we'll address critical safety issues surrounding
what has become a largely unregulated industry.
What is a vitamin?
For centuries, sailors on long voyages battled not only the high seas, but a disease that
can cause bones to become brittle, gums to bleed and even death. That disease is scurvy.
It had long been suspected there might be a relationship between the lack of fresh food
and the development of scurvy, but it wasn't until 1747 that a carefully planned trial
showed that lemons and oranges would prevent the disease. It took until 1928, when the
science of chemistry was more advanced, for a researcher to identify the substance in
lemons and oranges (and many other fruits and vegetables) that prevents or cures scurvy.
The substance was given the name "vitamin C."
Most vitamins and minerals were discovered this way scientists identifying
substances you need because a shortage causes a health problem.
Vitamins and essential minerals are substances required in tiny amounts to promote
essential biochemical reactions in your cells. Together, vitamins and minerals are called
micronutrients. Lack of a micronutrient for a prolonged period causes a specific disease
or condition, which can usually be reversed when the micronutrient is resupplied.
Your body can't make most vitamins and minerals. They must come from food or supplements.
Vitamin and mineral ABCs
There are 13 vitamins. Four vitamins A, D, E and K are stored in your body's
fat (they're called fat-soluble vitamins). Nine are water-soluble and are not stored in
your body in appreciable amounts. They are vitamin C and the eight B vitamins: thiamine
(B-1), riboflavin (B-2), niacin, vitamin B-6, pantothenic acid, vitamin B-12, biotin and
folic acid (folate).
Vitamins in the right amounts are needed for normal growth, digestion, mental alertness
and resistance to infection. They enable your body to use carbohydrates, fats and
proteins. They also act as catalysts in your body, initiating or speeding up a chemical
reaction. However, you don't "burn" vitamins, so you can't get energy (calories)
directly from them.
Your body strives to maintain an optimal level of each vitamin and keep the amount
circulating in your bloodstream constant. Surplus water-soluble vitamins are excreted in
urine. Surplus fat-soluble vitamins are stored in body tissue. Because they're stored,
excess fat-soluble vitamins can accumulate in your body and become toxic. Your body is
especially sensitive to too much vitamin A and vitamin D.
Therefore, whether you're taking water-soluble or fat-soluble vitamin supplements, more is
not necessarily better and can even be harmful.
Your body also needs 15 minerals that help regulate cell function and provide structure
for cells. Major minerals include calcium, phosphorus and magnesium. In addition, your
body needs smaller amounts of chromium, copper, fluoride, iodine, iron, manganese,
molybdenum, selenium, zinc, chloride, potassium and sodium.
Do you need a vitamin-mineral supplement?
Vitamin hucksters spend millions planting the fear, "Are you getting enough
vitamins?" They recommend vitamin, mineral and nutritional supplements as
"vitamin insurance." But there's no need for most people to bank on vitamin
insurance. The American Dietetic Association, the National Academy of Sciences, the
National Research Council and other major medical societies all agree that you should get
the vitamins and minerals you need through a well-balanced diet. Although certain
high-risk groups may benefit from a vitamin-mineral supplement, healthy adults can get all
necessary nutrients from food.
Experts favor food, rather than supplements, because food contains hundreds of additional
nutrients, including phytochemicals. Phytochemicals are compounds that occur naturally in
foods and may contain important health benefits. Scientists have yet to learn exactly what
role phytochemicals play in nutrition, and there's no RDA established for them. However,
if you depend on supplements rather than trying to eat a variety of whole foods, you miss
out on possible health benefits from phytochemicals.
In addition, only long-term, well-designed studies can sort out which nutrients in food
are beneficial and whether taking them in pill form provides the same benefit. In the
meantime, it's best to concentrate on getting your nutrients from food, not supplements.
However, many people don't get all the nutrients they need from their diets because they
don't eat properly. For example, only one person in 10 regularly consumes the recommended
five servings a day of fruits and vegetables. Skipping meals, dieting and eating meals
high in sugar and fat all contribute to poor nutrition. For these people, taking
supplemental vitamins would be reasonable, although the best course of action would be to
adopt better eating habits.
Vitamin-mineral supplements shouldn't substitute for a healthful diet. However, there's
probably no harm in taking a multiple vitamin-mineral supplement with dose levels no
higher than 100 percent of the Daily Value . Doses above that don't give extra protection,
but do increase your risk of encountering toxic side effects.
For example, taking large amounts of vitamin D can indirectly cause kidney damage, while
large amounts of vitamin A can cause liver damage. Even modest increases in some minerals
can lead to imbalances that limit your body's ability to use other minerals. And
supplements of iron, zinc, chromium and selenium can be toxic at just five times the RDA.
Virtually all nutrient toxicities stem from high-dose supplements.
When you may need a supplement
Although most people can get all the vitamins and minerals they need from a balanced diet,
there are situations where a supplement may be appropriate. Even if you don't have a
documented deficiency, your doctor or dietitian may recommend a vitamin-mineral supplement
if:
You're older Lack of appetite, loss of taste and smell, and denture problems
can all contribute to a poor diet. If you eat alone or are depressed, you also may not eat
enough to get all the nutrients you need from food.
In addition, if you're age 65 or older, you may need to increase your intake of vitamin
B-6, vitamin B-12 and vitamin D because your body may not be able to absorb these as well.
And women, especially those not taking estrogen, may need to increase their intake of
calcium and vitamin D to protect against osteoporosis.
There's also evidence that a multivitamin may improve your immune function and decrease
your risk for some infections if you're older.
You're on a strict weight-loss diet If you eat less than 1,000 calories a
day, or your diet has limited variety due to intolerance or allergy, you may benefit from
a vitamin-mineral supplement.
You have a disease of your digestive tract Diseases of your liver,
gallbladder, intestine and pancreas, or previous surgery on your digestive tract, may
interfere with your normal digestion and absorption of nutrients. If you have one of these
conditions, your doctor may advise you to supplement your diet with vitamins and minerals.
You smoke Smoking reduces vitamin C levels and causes production of harmful
free radicals (see "Vitamin and mineral supplements in the headlines"). The RDA
for vitamin C for smokers is higher 100 milligrams (mg) compared to 60 mg for
nonsmokers. Still, you can easily get this much by eating foods rich in vitamin C. If you
smoke, try to stop. And don't depend on high-potency supplements to provide necessary
nutrients. Two studies of beta carotene have shown an increased risk of lung cancer in
smokers who take these supplements.
You drink alcoholic beverages to excess If you regularly consume alcohol to
excess, you may not get enough vitamins due to poor nutrition and alcohol's effect on the
absorption, metabolism and excretion of vitamins.
You're pregnant or breast-feeding If you're pregnant or breast-feeding, you
need more of certain nutrients, especially folic acid, iron and calcium. Your doctor can
recommend a supplement.
You're in another high-risk group Vegetarians who eliminate all animal
products from their diets may need additional vitamin B-12. And if you have limited milk
intake and limited exposure to the sun, you may need to supplement your diet with calcium
and vitamin D.
Supplement safety
For the millions of healthy Americans who want to take a daily multivitamin supplement
with no more than 100 percent of the Daily Value, the risks of side effects are probably
small. But if you're tempted to take high-dose vitamins, thinking that "more is
better," think again. High doses of some vitamins can have serious side effects.
And if you're considering herbal and other types of supplements, be particularly cautious.
Quality and dose potency may not be well-regulated.
For example, in 1989, a sudden illness outbreak that affected more than 1,500 people and
caused 38 deaths was linked to L-tryptophan, an amino acid sold as an over-the-counter
dietary supplement to treat insomnia. The supplements, manufactured by a foreign
pharmaceutical company, were contaminated during the manufacturing process.
Today, experts are concerned about reported health problems linked to popular herbal
supplements containing ephedrine. Although the FDA has linked the supplements to more than
600 reports of adverse events and 15 deaths since 1993, they're still on the market.
Reported side effects have included abnormal heart rhythm, seizure, stroke, psychosis,
heart attack, hepatitis and death. The FDA is considering a ban on ephedrine-containing
supplements because no safe level has been identified for its use in dietary supplements.
Here's a list of health effects of some widely promoted
herbal supplements:
Comfrey
Also called borage and coltsfoot, it can cause liver and kidney disease.
Chaparral
Nontoxic when used in a tea, chaparral can cause acute
toxic hepatitis (liver disease) when taken in pill form.
Echinacea
May increase resistance to upper respiratory infections,
but continued use decreases effects. Some allergic reactions have been reported.
Ephedrine-containing compounds
Ephedrine is a drug that stimulates heart rate. It can cause stroke and dangerous
increases in blood pressure. Products are sold under the names Ma Huang, Ephedra, Ultimate
Xphoria and others.
Germanium
Long-term use can lead to kidney damage and, reportedly,
has been linked to a death.
Ginkgo biloba
May dilate blood vessels and improve blood flow to your
brain and aid circulation in your legs, but side effects can include gastrointestinal
problems, headaches and allergic skin reactions.
Ginseng
Ginsenosides, the active ingredients found in ginseng root, may enhance immunity, but many
"ginseng" products contain little or none of the active ingredient. Ginsenosides
can increase blood pressure.
Jin bu huan
A sedative that has caused hepatitis in adults and
drowsiness, slow heartbeat and slow breathing in children.
Kombucha tea
This "herbal tea," also called mushroom tea,
kvass tea, kwassan and kargasok, is really a colony of yeast and bacteria. Reportedly, it
can cause liver and other organ damage, gastrointestinal upset and has been linked to a
death.
Lobelia
Also called Indian tobacco, low doses act like a mild stimulant to help open airways and
ease breathing. Large doses can cause convulsions, coma and death.
St. John's wort
May be an effective treatment for mild to moderately severe
depression. Further studies for possible side effects are needed.
Saw palmetto
May improve urinary flow in men with noncancerous enlarged prostate. Teas made from saw
palmetto aren't effective. Use with a doctor's supervision, not as a substitute for
conventional medical treatment.
Stephania
Also called magnolia. Used in weight-loss preparations, this herb has caused kidney
disease and resulted in kidney transplants and dialysis in Europe.
Yohimbine
Sold as an aphrodisiac (for which it's ineffective),
yohimbine can cause tremors, anxiety, high blood pressure and rapid heartbeat.
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