These Vitamins May Lower Death Risk, But Only If You Get Them From Food

Another study has warned that vitamin supplements probably aren't an adequate substitute for a poor diet — and, in fact, at least one popular supplement may increase cancer death risk. Though some nutrients have been linked to lower mortality risk in general, you'll need to get those nutrients from actual food, not pills and powders, to reap the benefits.

The study comes out of Tufts University, where researchers found that taking excessive calcium supplements may increase one's risk of dying from cancer. In this case, 'excessive' means more than 1,000mg per day. In addition, the study found that taking dietary supplements didn't lower the risk of death in participants, which included US adults ages 20 and older.

Dietary supplements have remained controversial for a number of reasons, including lack of adequate regulations that result in many poor quality products that, in some cases, contain little or no active ingredients. In addition, some past research has indicated that taking supplements — rather than getting the nutrients from food — may increase the risk of certain health problems rather than protect against them.

Though the study found that getting adequate levels of vitamins A and K, as well as copper, magnesium, and zinc, was associated with reduced mortality, this benefit was only linked to food intake, not supplement use. There was no cancer death risk increase linked with calcium intake acquired from food rather than pills.

In addition to the excessive calcium risk link, the study also found evidence that taking vitamin D supplements if you don't have a deficiency may increase the risk of death. However, the researchers caution that more research is necessary to determine whether there's a link. It's important to note that the study involved self-reported dietary supplement use and dosage, and it's unclear whether specific usage durations may influence the outcome.