Supplements are a multibillion-dollar industry in America, but recent studies continue to call into question their usefulness. In a large analysis of 277 randomized trials, researchers from West Virginia University, Johns Hopkins and elsewhere found no proof that vitamin, mineral and other nutritional supplements could help stave off heart disease or prolong life, though there was some weak evidence that omega-3 fat supplements might be beneficial.

In another study, researchers at Tufts University analyzed dietary data from 30,899 U.S. adults and then followed the subjects for a median of 6 years. Their findings: Eating adequate amounts of vitamins and minerals from food was associated with fewer deaths from diseases like cancer, whereas vitamins and minerals from supplements had no protective effect.

And in JAMA Cardiology, a meta-analysis of 21 studies did not find evidence that vitamin D supplements reduce rates of heart disease or all-cause mortality.

Are there any supplements that you use and feel are effective? What do you say to (or ask) clients who are taking nutrition supplements? Do you believe people should focus on getting their nutrients from food instead of supplements?

 Send your answers to Sandy Todd Webster at [email protected]it.com.