FYI: Vitamins probably aren't doing anything for you

Sep 25, 2014 at 12:00 p.m. ET
Image: Aldo Murillo/E+/Getty Images

In some respects, despite problems with obesity and diabetes, we live in a "health nut" culture. We drink green juices, eat organic produce and go to trendy bikram yoga and spinning classes after work.

Oh yeah, and we take vitamins. A lot of them, according to New York mag’s "Science of Us" column. The industry tops $30 billion annually and has experienced an 85-percent growth boom since 2005 alone. Experts guess roughly half of American adults take some sort of vitamin supplement.

Too bad all that vitamin popping is probably not doing anything for us. University of Chicago econ professor Emily Oster took a look at some of the recent research on supplements, including two large studies from Harvard University and National Institutes of Health, and found zero correlation between taking vitamins and better health. In fact, it can even work against you, according to a study in Psychological Science. Vitamin-takers actually felt that because they'd done something "healthy," they could totally do something detrimental later like partake in a calorie splurge, hit a tanning bed or toss back shots. Eeek.

This misguided notion is something called "moral licensing" — which I'll let psychologist Wray Hubert explain: "Licensing is the notion that when we do something that we believe is good for us — like popping a vitamin — this action ironically gives us permission to engage in subsequent bad behavior — like munching potato chips — adding up to a net loss. We make these perverse trade-offs because doing something positive bolsters our 'health credentials,' which boosts our sense of invulnerability, which in turn encourages self-indulgence."

Not gonna lie to you, guys, I use this one all the time. My favorite is, "I deserve this lava cake because I had a salad for dinner! And I didn't even use the whole cup of dressing." ... Whoops.

So, back to vitamins. Unless your doc has told you to take a vitamin for a specific health-related purpose, you might be doing yourself a disservice by taking supplements. At best, you're probably doing nothing at all. (Sorry to bear the bad news!) Save your dough.

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