There is growing consensus among health professionals that most people should not be taking vitamin supplements. Their view is that this is a waste of money that will do no more than lead to expensive urine.
The standard advice is to eat a well-balanced diet. No one can argue with that sentiment, but what does it mean? A well-balanced diet is rarely defined beyond a vague idea of eating your vegetables. The USDA suggests that people should eat between five and nine servings of vegetables and fruits daily. For a person who consumes 2,000 calories a day, that works out to around two and a half cups of veggies and two cups of fruit a day. In reality, not many Americans actually manage that many servings of produce.
As a result, many people fall short on the vitamins and minerals they need for good health. This is especially true for people who take medications on a regular basis. The consequence is that many should be taking vitamin supplements, or possibly minerals.
Magnesium is an essential mineral that is frequently low in American diets. The best sources are green leafy vegetables, nuts, fruits such as figs or raspberries and various types of beans.
Even people who do eat fruits and vegetables could still find themselves in trouble if they must take certain pills for heartburn or high blood pressure, for example. Acid-suppressing drugs like esomeprazole (Nexium), lansoprazole (Prevacid) and omeprazole (Prilosec) limit magnesium absorption. ACE inhibitors such as enalapril or lisinopril deplete magnesium and zinc. So do thiazide diuretics like hydrochloriothiazide (HCTZ).
Low magnesium levels have been linked to depression, diabetes, high blood pressure, heart disease and arrhythmias. Symptoms include insulin resistance, severe menstrual cramps, leg cramps, fatigue and migraine headaches.
A word about zinc: most people don’t think about it very much. Low levels can lead to changes in the senses of taste and smell, slower wound healing, diarrhea and hair loss.
Vitamin B12 is another critical nutrient that may be affected by medication. This vitamin is found in meat, fish, poultry, dairy products and eggs, so people following vegetarian and vegan diets may come up short. The acid-suppressing medications mentioned above can also interfere with vitamin B12 absorption. That’s because the stomach needs acid to absorb vitamin B12 adequately. Older people, whose stomach acid production often drops dramatically, are at risk of vitamin B12 insufficiency.
In addition, the diabetes drug metformin can also lead to inadequate vitamin B12. More than 80 million prescriptions for metformin are dispensed annually. That doesn’t include millions more for combination diabetes drugs like Janumet that include metformin.
Certain antibiotics such as doxycycline, ciprofloxacin and co-trimoxazole can also affect vitamin B12 absorption.
Vitamin B12 deficiency can lead to serious complications such as neuropathy, which can cause burning, tingling and numbness. Low levels can also contribute to cognitive impairment and mood disorders. People who must take such medicines should ask their doctors to monitor their vitamin B12 levels periodically.
There are studies going back several years demonstrating that vitamin supplements can be helpful in certain situations that may be relevant for you. We got this question from a reader in 2014:
Q. Is it true that taking vitamins is a waste of money since they do not improve our health?
A. An editorial in the Annals of Internal Medicine (Dec. 17, 2013) titled “Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements” makes this argument. We don’t entirely agree, however.
Some studies have shown that certain vitamins can improve cognitive function, reduce the risk of cancer or lower the chance of getting cataracts (JAMA, Jan. 1, 2014 & Nov. 14, 2012; Ophthalmology, Feb. 2014).
You can learn more about the pros and cons of nutritional supplements and the interactions of drugs and nutrients from Fortify Your Life: Your Guide to Vitamins, Minerals, and More. The author is Dr. Tieraona Low Dog, one of the country’s leading experts on dietary supplement and integrative medicine. It is now available in paperback only from www.PeoplesPharmacy.com.
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