Harvard Study Suggests Vitamin D Has No Effect on Cardiovascular Health

Updated November 8, 2024, at 6:05 p.m.

Vitamin D supplementation does not reduce the risk of cardiovascular disease, researchers reported in a September paper.

The study — conducted by scientists at Beth Israel Deaconess Medical Center, a Harvard Medical School teaching hospital, and published in the American Journal of Preventive Cardiology — found that while Vitamin D deficiency is associated with cardiovascular disease, increasing individuals’ intake of the vitamin through supplements did not improve blood markers of heart health.

The BIDMC researchers used data from a four-year National Institute of Aging-sponsored trial that assessed the impact of different doses of Vitamin D on adults aged 70 or older with an elevated risk of falling.

“We collected serum and blood and tried to understand if the Vitamin D supplements would have an impact on biomarkers,” said Lawrence J. Appel, a professor at Johns Hopkins University and co-author on the study.

The team found that varying doses of Vitamin D given to trial participants had “absolutely no benefit at all” to their health outcomes, Appel said.

Researchers found that participants taking higher doses of Vitamin D supplements may be more likely to fall and experience harm than those taking lower doses.

Appel emphasized the measurement of number of falls in study participants, recorded daily and in precise detail, as a unique contribution of the study.

“If anything, there was the signal for harm with somewhat increased risk of falls with hospitalization and falls with serious adverse events,” he said.

Researchers pointed to alternative measures that may be more productive at preventing cardiovascular disease than Vitamin D.

“There are studies that show that doing moderate intensity exercise regularly reduces your risk of cardiovascular disease,” Rainer said. “There’s been a lot of trials focused on sort of the DASH diet, or a low sodium diet, or the Mediterranean diet, that, again, look at cardiovascular disease risk.”

Appel discouraged further research into the impacts of Vitamin D.

“I spend my time trying to understand interventions that have a benefit, and I stopped really studying Vitamin D because, quite frankly, I don’t think that intervention has a major public health impact,” he said.

“Stop funding major studies of Vitamin D,” Appel said.

Instead, he encouraged funding studies on potassium supplements and intake, suggesting that diets high in potassium and low in sodium may be more effective in preventing cardiovascular disease.

“I think it’s over $25 billion spent per year on vitamin supplements which really have no benefit,” Appel said. In 2021, Americans spent close to $50 billion on vitamins and dietary supplements.

“It’s like the world is impervious to truth,” Appel said. “Any mainstream nutritionists, those who are open minded, evidence driven, they feel the same way. It’s just there’s not evidence enough to recommend vitamin supplements for almost any indication.”