If taking calcium supplements is bad for the heart, as new research suggests, what's the best way to get the essential nutrient?
The Johns Hopkins School of Medicine researchers found calcium from food sources — not pills — lowered the risk of developing calcium deposits in the arteries, an early sign of plaque build-up. So increasing the consumption of calcium-rich foods could be a way to protect both bones and hearts.
The minimum daily calcium requirement for women under 50 is 1,000 milligrams; for women over 50, it's 1,200. According to Leslie Bonci, a registered dietitian and owner of Active Eating Advice, these are some of the best food sources of calcium:
milk, 8-ounce glass: 300 mg
cottage cheese, 1/2 cup: 65 mg
soy milk, calcium fortified, 8 ounces: 200-400 mg
yogurt, 1 cup: 450 mg
cheese, 1 ounce: 50-270 mg
kale, 1 cup: 55 mg
orange juice, 1 cup fortified with calcium: 300 mg
tofu calcium set, 4 ounces: 250-750 mg
cereals, calcium fortified, 1 ounce: 250-1000 mg
almonds, 1 ounce: 80 mg
sesame seeds,1 ounce: 280 mg
chia seeds,1 ounce: 180 mg
canned salmon, 2 ounces: 170-210 mg
sardines, 3 ounces: 370 mg
Fortified foods, like soy milk and orange juice, may be a good choice for those who can’t tolerate dairy, experts said. Don't worry that it's like taking a supplement; you’re not taking the calcium by itself.
It's not clear, but problems with calcium supplements may be related to taking the pills all at once. That burst “can transiently increase blood levels of calcium,” said Dr. Erin Michos, an associate professor of medicine in the division of cardiology and the associate director of preventive cardiology at the Johns Hopkins School of Medicine. “It can then be deposited in other tissues including the blood vessels."
If that theory is right, Michos said, it’s possible the heart risk could be avoided if people took supplements in small doses throughout the day rather than all at once.
“If you don’t take it with a meal, you can’t be guaranteed it will be absorbed normally," said Dr. Robert Recker, the O’Brien Professor of Medicine and director of the Osteoporosis Research Program at Creighton University. “There are some people who don’t absorb it at all if they don’t take it with a meal.”
Avoid high doses
Cardiologist Dr. Kathryn Berlacher isn't ready to tell her patients to toss their calcium supplements. Because the new study was observational — meaning people decided on their own whether they would take supplements or not — it's possible that people who chose not to take supplements might have something in common that protects against atherosclerosis or that the people taking supplements might have an unaccounted for factor driving them to develop calcium deposits in their arteries.
However, for now, the most sensible approach would be to cut back on supplements and increase the amount of the mineral coming from dietary sources, said Berlacher.
“I don’t think it means you have to stop taking them completely, but you have to be careful not to take high doses,” said Berlacher, an assistant professor at the University of Pittsburgh School of Medicine and director of the Women’s Heart Program at the University of Pittsburgh Medical Center.
It's important to get enough calcium, Bonci said. “If you can do it with diet alone, that’s all well and good,” she added. “But you have to be consistent.”