Do Large Vitamin Doses Make You Healthier?

QUESTION: Do large doses of vitamins really help you be healthier?
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ANSWER: Despite the beliefs of some, the only answer I can give that respects
current medical knowledge is "No". In fact, large doses of some vitamins can
hurt you. Vitamins, like anything else, are helpful when taken in moderation.
Be informed about vitamins and what they can--and can't--do for you.
Vitamins are naturally-occurring substances that, in certain amounts, are
essential to good health. The Recommended Daily Allowance (RDA) has been set
for all vitamins by the National Institutes of Health, and the RDA indicates
the minimum amount of each vitamin that is required to avoid a deficiency.
Vitamins are usually used in small amounts; vitamins can be powerful "drugs"
if they are used in large amounts. Anytime vitamins are administered in
excess amounts, the patient should be carefully monitored for signs of vitamin
overdose. Regularly exceeding the RDA by prescribing vitamin supplements to
yourself is not wise, because vitamins can have profound side effects.
The fat-soluble vitamins, especially A and D, are maybe the best known
for their toxicity in large doses. However, the water-soluble vitamins can be
toxic in large doses also. It seems that the quickest way to learn about the
toxicity of large doses of a vitamin is to follow the health and diet fads--if
a particular fad calls for large amounts of vitamins, you can be sure that
toxicity will soon follow.
Beware of anyone, in or out of health care, who advocates large amounts
of vitamins to "cure" a health problem. Besides the health problems it can
cause, taking large amounts of vitamins can be an enormous waste of money. If
you are eating a well-balanced diet, you're probably getting plenty of
vitamins every day. If you're not sure, keep track of your food intake for a
few days, and consult a registered dietitian or your physician. Chances are
any vitamin deficiencies can be made up with a modification in your diet.
There are a few vitamins that are useful in large amounts to certain
people. At no time should these vitamins be self-administered without the
guidance of a physician.
Niacin, or nicotinic acid, has a healthy effect on the blood fats, which
is important to the person with coronary artery disease. Niacin can lower the
"bad" cholesterol in the blood, elevate the "good" cholesterol and decrease
triglycerides. Its toxic effects range from nuisances such as flushing of the
skin to more infrequent but serious hepatitis and hyperglycemia.
Pyridoxine has been used to treat premenstrual syndrome (PMS), carpal
tunnel syndrome and asthma. Toxic effects center on the central nervous
system, and they may range from mild sensory loss to inability to walk.
Vitamin A is well-known for its role in good vision and in healthy skin
and membranes. It can be helpful in treating psoriasis, acne, ichthyosis and
Darier's disease. The oral as well as the topical (lotion) forms are used.
The main problems with Vitamin A toxicity are severe liver problems as well as
swelling of the brain. Both problems can result in death, so Vitamin A should
only be used with great caution.
Popular but of questionable value in large doses are Vitamin C,
pantothenic acids and Vitamin E. Remember that these vitamins, like any
substances taken in large amounts, can cause as many problems as they solve.
Instead of spending money on large amounts of vitamins, spend your money on a
variety of nutritious food. You'll enjoy it and chances are you'll be
healthier, too.