BOSTON (April 8, 2019, 5:00 p.m. ET)—Adequate intake of certain nutrients is associated with a reduction in all-cause mortality when the nutrient source is foods, but not supplements, according to a new study. There was no association between dietary supplement use and a lower risk of death.
In addition, excess calcium intake was linked to an increased risk of cancer death, which the researchers found was associated with supplemental doses of calcium exceeding 1,000 mg/day. The study was published on April 9 in Annals of Internal Medicine.
“As potential benefits and harms 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,” said Fang Fang Zhang, M.D., Ph.D., associate professor at the Friedman School of Nutrition Science and Policy at Tufts University and senior and corresponding author on the study. “It is important to understand the role that the nutrient and its source might play in health outcomes, particularly if the effect might not be beneficial.”
The study used a nationally representative sample comprised of data from more than 27,000 U.S. adults ages 20 and older to evaluate the association between dietary supplement use and death from all causes, cardiovascular disease (CVD), and cancer. The researchers assessed whether adequate or excess nutrient intake was associated with death and whether intake from food versus supplement sources had any effect on the associations.
For the association between nutrient intake and the risk of death, the researchers found:
- Adequate intakes of vitamin K and magnesium were associated with a lower risk of death;
- Adequate intakes of vitamin A, vitamin K, and zinc were associated with a lower risk of death from CVD; and
- Excess intake of calcium was associated with higher risk of death from cancer.
When sources of nutrient intake (food vs. supplement) were evaluated, the researchers found:
- The lower risk of death associated with adequate nutrient intakes of vitamin K and magnesium was limited to nutrients from foods, not from supplements;
- The lower risk of death from CVD associated with adequate intakes of vitamin A, vitamin K, and zinc was limited to nutrients from foods, not from supplements; and
- Calcium intake from supplement totals of at least 1,000 mg/day was associated with increased risk of death from cancer but there was no association for calcium intake from foods.