Supplements have a downside.

Recently, the Journal of the American Medical Association published an article titled “Why Do U.S. Adults Use Dietary Supplements?” I’ve asked the same question myself. I’ve noticed that so many “intelligent” people seem to me to be popping pills left and right that they don’t need.

I’ll grant you that some supplements are useful. For example, I recommend a multivitamin for everyone every day, although many of my colleagues poo-poo it. And I’m a proponent of an extra 1000u of vitamin D. But some people are taking a handful of pills and capsules every morning.

The researchers discovered that most supplement takers are educated, exercise more, eat better and drink less than the overall population. They are more likely to engage in wellness activities. Now, I don’t think the “supplements made them do it,” but rather that they’ve taken the “I want to be as healthy as I can” route.

Congratulations and kudos, I say. But are the supplements necessary? This question is especially important, since they may have a downside.

I used to say if you want to spend your money in the supplement aisle go right ahead – I’ll stay with fruits and vegetables, thank you. I also said that it was a “no harm, no foul” situation, as supplements were safe.

Well guess what? I was wrong.

Let’s begin with my first wake-up call – beta carotene. I used to recommend taking it to prevent cancer because we know that people who consume foods rich in beta carotene such as broccoli, squash and carrots, for example, have less cancer.

Then a major study (conveniently labeled the CARET study, for Beta Carotene and Retinol Efficacy Trial) showed that smokers who took beta carotene and continued to smoke actually had more lung cancer. That’s right! Beta carotene supplements somehow encouraged cancer.

Since that time, this once-hot supplement has cooled down. You rarely hear anyone touting its usefulness anymore. When I started recommending against beta carotene, you should have heard the angry letters that flooded my inbox. I was accused of being in bed with the FDA, of being a pill pusher, of being a charlatan or just plain dumb. That’s when I realized that for some people, supplements are akin to a religion.

I started recommending that people spend more money in the grocery store and less in the drugstore. My general rule of thumb is color. The deeper and more colorful the fruit or vegetable, the more loaded it is with vitamins, minerals and other nutrients such as beta carotene and antioxidants. Fresh is best, followed by frozen and then canned.

So back to the “it can’t do any harm so take it” idea that I used to believe. Two new studies just published in JAMA dispute this – they look at the side effects of vitamin C and calcium, both widely used supplements.

My spin: Manufactured supplements, even those that call themselves natural or organic, are never natural because Mother Nature never made a pill in her life. Stick by her side and you’ll be peachy keen. Stay well.

Dr. Zorba Paster is a family physician, university professor, author and broadcast journalist.