Vitamin D supplements lower blood pressure in seniors who are obese. This reduces their heart health risk, a new study says. The Journal of the Endocrine Society published it.
However, researchers warn against taking more than the recommended daily dose. It will not provide additional health benefits.
“Our study found vitamin D supplementation may decrease blood pressure in specific subgroups such older people, people with obesity and possibly those with low vitamin D levels,” said researcher Dr. Ghada El-Hajj Fuleihan of the American University of Beirut Medical Center in Beirut, Lebanon.
The recommended daily dose of vitamin D is 600 IU, or about 15 micrograms.
How they studied effects of the vitamin on blood pressure
For the study, researchers tracked the health of 221 seniors with obesity who took either 600 IU or 3,750 IU of daily vitamin D supplements for a year.
The supplements did lower their blood pressure, as the results showed. But higher doses did not provide additional benefits.
“High vitamin D doses compared to the Institutes of Medicine’s recommended daily dose did not provide additional health benefits,” Dr. El-Hajj Fuleihan said.
Supplementation with vitamin D plus calcium helps lower blood pressure in older adults with obesity (body mass index (BMI) greater than 30).
Why vitamin D might affect blood pressure
Reimas Geiga, MD, a medical doctor, registered dietitian, and clinical nutritionist with Glowbar LDN, explained that vitamin D can affect blood pressure in several ways.
“One of the primary ways is by aiding in calcium regulation,” he said, “which is crucial for the contraction and relaxation of blood vessels. By improving vascular function, vitamin D could help reduce blood pressure.”
Additionally, in those with obesity, there is chronic, low-grade inflammation, said Geiga. This can impair blood vessel health, contributing to high blood pressure.
“Vitamin D has known anti-inflammatory properties that may help counteract this effect,” he explained. “Moreover, people with obesity are more likely to experience vitamin D deficiency because fat cells can store vitamin D, reducing its availability to the body.”
According to Geiga, supplementation back to adequate levels can help improve vascular health and lower blood pressure.
“Additionally, vitamin D influences the renin-angiotensin-aldosterone system, a key regulator of blood pressure,” he said. “Adequate vitamin D levels may reduce the activity of this system, leading to better blood pressure control.”
Are vitamin D supplements right for you?
Given that vitamin D is easy to obtain, patients may wonder how they can apply the study’s findings to their own lives.
Dr. Rita Hawle, a clinical dietitian and nutritionist with ClinicSpots, says the first step is determining whether you are actually low in vitamin D.
“A simple blood test can reveal any deficiency that may be contributing to blood pressure issues,” she said. “If levels are low, supplements or a bit of natural sunlight exposure (when safe) can help improve vitamin D status over time.”
However, she added that vitamin D supplementation really needs to be a part of a larger strategy.
“Blood pressure responds well to a combined approach: regular exercise, a heart-healthy diet, and effective weight management are all important for long-term benefits,” said Hawle.
Additionally, while the study looked at supplementation with 600 IU and 3,750 IU doses, she advises speaking with your physician about what is an appropriate dose for you.
Vitamin D can accumulate in the human body, leading to a toxic build-up of calcium.
“This study provides encouraging insights,” Hawle concluded, “but it’s best to view vitamin D as part of a larger wellness plan, particularly for individuals managing both obesity and high blood pressure.”
