Widely used drugs may be robbing you of important disease-fighting nutrients.

When we think of drug side effects, what usually comes to mind are headache, dizziness, dry mouth and other such complaints.

Commonly ignored side effect: Many popular medications can deplete your body of crucial nutrients—an unintended effect that can increase your risk for diseases ranging from cancer to heart disease. What you need to know…

ARE YOU AT RISK?

Nutrient depletion, which causes such symptoms as fatigue, muscle cramps and even a rapid heartbeat, can potentially occur within weeks after starting a medication.

More often, such symptoms occur gradually, over months or even years—and, as a result, often are dismissed by people taking the drugs as mere annoyances or mistaken for signs of aging.

In some cases, a hidden nutrient deficiency increases one’s risk for other illnesses—for example, a deficiency of folate (a B vitamin) may raise your risk for cancer or cause physiological changes that can set the stage for heart attack or stroke.

Important: If you take one or more medications regularly, ask your doctor about nutrient depletion—and whether you should be tested. Doctors can do a basic blood screening profile for low blood levels of vitamins and minerals, such as B-12, folate, calcium, magnesium and potassium.

However, to more accurately measure your levels of all the important nutrients, your doctor should consider more sophisticated testing.

For example, SpectraCell’s micronutrient test measures more than 31 vitamins, minerals, amino acids and antioxidants. Not all doctors are familiar with the test, but you can go to www.SpectraCell.com and click on “Find a Clinician” to locate a physician in your area who is. The panel costs around $325, and insurance may pay some of the cost. Or try the Metametrix Nutrient and Toxic Elements Profile, which costs from $79 to $164, depending on the specific tests (800-221-4640, www.Metametrix.com).

Helpful: Be sure to eat foods that are rich in nutrients that may be depleted by your medications. To ensure adequate levels of these nutrients, ask your doctor about taking the supplements described below. Drugs that can deplete nutrients…

ASPIRIN AND OTHER NSAIDs

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, are commonly used to reduce pain and inflammation. Millions of Americans also take aspirin to “thin” the blood, reducing the risk for a heart attack or stroke.

Nutrients depleted: Folate and vitamin C. Insufficient folate is thought to increase the risk for a variety of cancers, including malignancies of the breast and colon. Low folate also has been linked to elevated levels of homocysteine, an amino acid that can raise risk for heart attack and stroke.

People who are low in vitamin C get more colds, flu and other infections than those with normal levels. A deficiency of vitamin C also can impair the body’s ability to produce and repair cartilage—which may explain why people with osteoarthritis who regularly take an NSAID often suffer more joint pain in the long run.

My recommendation: Take 1,000 mg of vitamin C daily if you take an NSAID regularly. A Boston University study found that people who got the most vitamin C were three times less likely to develop osteoarthritis, or have an increase in symptoms, than those who got lower amounts.

Caution: High-dose vitamin C can cause loose stools in some people—if this occurs, reduce your dose to 500 mg daily.

In addition, take a 400-mcg to 800-mcg folic acid (the man-made form of folate) supplement daily. Take vitamin B-12 (1,000 mcg daily) with folic acid—taking folic acid alone can mask a B-12 deficiency.

Also helpful: 1,000 mg to 2,000 mg of fish oil daily. One study found that 60% of people with osteoarthritis who took fish oil improved their joint pain within 75 days. Half improved so much that they no longer needed to take an NSAID.

CALCIUM CHANNEL BLOCKERS

When it comes to blood pressure medication, most people know that diuretics (water-excreting drugs) can deplete important nutrients, including potassium. It’s less well-known that blood pressure drugs known as calcium channel blockers, including amlodipine (Norvasc) and nicardipine (Cardene), can have the same effect.

Nutrient depleted: Potassium. People with low potassium may experience muscle weakness and fatigue. Their blood pressure also may rise, which offsets the drug’s effectiveness.

My recommendation: Take a 100-mg potassium supplement daily. Because many foods contain significant amounts of this mineral, you can eat a single extra serving of a high-potassium food as an alternative. A medium baked potato with the skin, for example, provides 850 mg of potassium… and a large banana has 487 mg. Check with your physician if you have kidney disease—extra potassium can worsen the condition.

GEMFIBROZIL

People who can’t control elevated cholesterol with a statin, or who suffer muscle pain or other side effects when taking a statin, may be given a prescription for gemfibrozil (Lopid). This and similar drugs, known as fibrates, raise levels of HDL (good) cholesterol and reduce harmful LDL cholesterol and triglycerides.

Nutrients depleted: Vitamin E and the naturally occurring nutrient coenzyme Q10 (CoQ10). A deficiency of vitamin E, a potent antioxidant, can increase risk for cancer, heart disease and other conditions, such as nerve disorders. Inadequate CoQ10 often results in muscle pain and weakness… and can impair the heart’s ability to beat efficiently.

My recommendation: Take 200 mg of CoQ10 and 100 mg of natural vitamin E (mixed tocopherols) daily.

metformin

Metformin (Glucophage), the most popular oral diabetes drug, reduces blood sugar by making cells more responsive to insulin. It also causes less weight gain and fewer episodes of hypoglycemia (excessively low blood sugar) than other diabetes drugs.

Nutrients depleted: Vitamin B-12. A study in Archives of Internal Medicine found that patients taking metformin had average vitamin B-12 levels that were less than half of those in people who weren’t taking the medication. Metformin also reduces levels of folate. A deficiency of these nutrients can cause fatigue, forgetfulness and depression.

My recommendation: Take 1,000 mcg of vitamin B-12 daily. Since many multivitamins have only 200 mcg (or less) of B-12, you’ll have to supplement to reach the 1,000-mcg daily dose. For folic acid, take 400 mcg to 800 mcg daily.

Important: When increasing levels of vitamin B-12, people with diabetes may be more likely to experience episodes of hypoglycemia. Ask your doctor about getting an A1C blood test, which measures blood sugar levels over a period of weeks rather than at a single point in time.