April 9 (UPI) -- Consuming too many nutrients, particularly when they come from supplements, may increase the risk of death, new research shows.
Taking in at least 1,000 milligrams of calcium a day from supplements is associated with a higher risk of cancer death, according to a study published Tuesday in the Annals of Internal Medicine. People with no vitamin D deficiency also faced an increased death risk when they consumed the nutrient in a supplement.
"As potential benefits and harm of supplement use continue to be studied, some studies have found associations between excess nutrient intake and adverse outcomes, including increased risk of certain cancers," Fang Fang Zhang, a researcher at Tufts University and study senior author, said in news release. "It is important to understand the role that the nutrient and its source might play in health outcomes, particularly if the affect might not be beneficial."
On the other hand, consuming adequate amounts of calcium from food had no association with cancer. And eating adequate amounts of vitamins A and K, magnesium and zinc from a food source could also lower death risk. Consuming some of those nutrients could even reduce cardiovascular risks, the study says.
In contrast, past studies have shown that consuming calcium from supplements may increase cardiovascular disease.
"Our results support the idea that, while supplement use contributes to an increased level of total nutrient intake, there are beneficial associations with nutrients from foods that aren't seen with supplements," Zhang said. This study also confirms the importance of identifying the nutrient source when evaluating mortality outcomes. "