A trip to the health food store can be
daunting these days. The consumer is typically confronted by shelf after shelf
of vitamins, minerals, herbs, and other so-called natural substances, all
touted as enhancing well-being in some way. Many of these over-the-counter
products make subtle claims about their effects on mood, thinking, or energy --
without providing scientific data to back up those claims.
Because many of these preparations are classified as
"food substances," the U.S. Food and Drug Administration (FDA) cannot
regulate them as real drugs. In effect, it's up to the FDA to prove that a food
substance is unsafe, rather than the job of the manufacturer to show it is
safe. What is the evidence that vitamins, minerals, or similar substances have
an effect on mood disorders? And can these substances actually improve moods or
even treat depression?
Antidepressants, especially when combined with talk therapy, generally help people recover from depression. Symptoms begin to improve within weeks for the majority of people taking antidepressants. And people who take antidepressants long-term -- up to 36 months -- have a relapse rate of only 18% compared to 40% for those who do not.
But if they work so well, why do so many people stop taking antidepressants within a few weeks of starting them? Or skip doses when they start to feel better?
Vitamin deficiencies are rare in the United States and other
developed countries. In fact, vitamin excess may now be more common than
vitamin deficiency. When deficiencies do occur, they're usually due to food
fads that lead to medical conditions from poor absorption of nutrients in the
intestine, or inborn errors in the way nutrients are handled. Alcoholism is
also a major cause of vitamin deficiencies, owing to poor nutrition, impaired
absorption of nutrients, and other factors. The elderly and those with mental
illness or mental retardation are also at risk, usually due to poor nutrition
Occasionally there are individuals whose depression,
anxiety, or memory problems are caused by a deficiency in some vitamin,
mineral, or trace element -- most commonly, one of the B complex vitamins.
Deficiencies of thiamine (vitamin B1), niacin, pyridoxine (B6), or cobalamin
(B12) sometimes produce mental or emotional problems, including depression.
Folic acid deficiency may cause problems with mood and mental function. While
only a small minority of severely depressed persons suffer from such vitamin
deficiencies, this problem must be ruled out when the clinical picture raises
suspicions -- for example, when a depressed individual has a history of bowel
surgery that may have led to malabsorption of B vitamins. If depression is due
to a vitamin deficiency, treatment must include replacement or supplementation
of the vitamin before the patient can fully recover.
Interest in Chromium
Recently there has been great interest in a trace element
called chromium. (Trace elements are metals, such as zinc or copper, that are
found in very small amounts in the human body and are necessary for various
vital functions.) It has been known for many years that chromium is essential
for the way our bodies handle sugar. Chromium deficiency makes it hard for
cells and tissues to make use of glucose, a simple sugar. This problem is
especially serious in people with diabetes, in whom deficiency of the hormone
insulin already creates problems with high blood sugar. But the role of
chromium in depression is only now emerging. A recent study by Dr. Malcolm
McLeod and his colleagues investigated the use of chromium in five patients
with a chronic form of depression called dysthymia. In one case, a patient who
had not responded well to a Prozac-type antidepressant decided on his own to
add chromium to his medication. Within a few days he was feeling dramatically
better. Several other cases reported by McLeod also seemed to show marked
improvement when chromium was added to the patients' regular antidepressant