Stroke May Lead To Lower Vitamin D

Low vitamin D levels do not lead to strokes but can result from them.

Vitamin D is mostly known for helping the body absorb calcium and contributing to bone health. But research in recent decades also has looked at whether vitamin D levels affect cardiovascular disease, although with inconsistent results.

The new study looked at vitamin D levels among 9,680 people from the Dutch city of Rotterdam. It found people with low levels of the vitamin were more likely to have reported having a stroke in the past.

After excluding people who had already had a stroke, researchers tracked the remaining group over the next 10 years. They found no association between vitamin D levels and higher stroke risk. They did, however, notice the people who had strokes during the follow-up years were more likely to have a severe vitamin D deficiency.

The reason behind this was not explored by researchers, said Dr. Kamran Ikram, senior author of the study published Thursday in the American Heart Association’s journal Stroke.

“When we started this study, our basic question was to see whether the vitamin D level proceeds the stroke. We just looked at one small, tiny piece of the puzzle,” said Ikram, a professor of neurology and epidemiology at Erasmus University Medical Center in Rotterdam, the Netherlands. “The question now is, once somebody has a stroke, do we then have to do something with the vitamin D? That question we haven’t tackled in the study.”

The study did suggest people who have strokes “may have limited vitamin D production because of reduced exposure to sunlight and diet quality, among other factors.” But Ikram said there’s no clear evidence to support taking vitamin D supplements to reduce stroke risk.

A recent compilation of past studies found an increased risk for stroke in people who had very low vitamin D levels. Yet, a study released in July found taking vitamin D supplements, along with calcium, could increase stroke risk.

Vitamin D can build up in the body to toxic levels when taken in excess, said Dr. Tanya Turan, a neurologist who wasn’t involved in the study.

“Most of the general public doesn’t know that. They think vitamins – the more I take, the better, the healthier I’m going to be,” said Turan, a vascular neurology professor at Medical University of South Carolina in Charleston. “But for the majority of people who eat a normal, well-balanced diet, they don’t need vitamin supplementation. Most of what you need will come through diet and a mild amount of sun exposure.”

While some research suggests treating low vitamin D levels after a stroke may result in better stroke recovery, more studies are needed, Turan said. “When it comes to vitamin D deficiency, it’s probably better to try and identify what’s the underlying cause of that – is there an intestinal absorption issue? Is there poor nutrition?”

“In cases where severe vitamin D deficiency is detected, it makes sense to supplement for other reasons, like bone health and all the things we know that vitamin D can benefit,” Turan said. “To do it solely for stroke prevention doesn’t seem warranted at this time.”

If you have questions or comments about this story, please email editor@heart.org.

American Heart Association News Stories

American Heart Association News covers heart disease, stroke and related health issues. Not all views expressed in American Heart Association News stories reflect the official position of the American Heart Association.

HEALTH CARE DISCLAIMER: This site and its services do not constitute the practice of medical advice, diagnosis or treatment. Always talk to your health care provider for diagnosis and treatment, including your specific medical needs. If you have or suspect that you have a medical problem or condition, please contact a qualified health care professional immediately. If you are in the United States and experiencing a medical emergency, call 911 or call for emergency medical help immediately.



Health Topics

Urinary tract and other infections may trigger different kinds of stroke

Several infections have been identified as possible stroke triggers, with urinary tract infections showing the strongest link with ischemic stroke. Previous research examined infections as triggers of stroke, but were limited to the correlation of acute infections with ischemic stroke, a type of stroke caused by blocked blood vessels...

Continue reading

Undetected diabetes linked to heart attack and gum disease

People with undetected glucose disorders run a higher risk of both myocardial infarction and periodontitis, according to a new study. The results demonstrate the need of greater collaboration between dentistry and healthcare, say the researchers, and possibly of screening for diabetes at dental clinics. Severe periodontitis is already known...

Continue reading

On Call with Dr. Lyons

As summer quickly comes to an end, our thoughts reluctantly begin to focus on Back to School. We start getting our homes “in order”, clothes and school supply shopping, cleaning out the summer sun, sand and fun of our thoughts so we can refocus our minds on the upcoming school year and all it brings. With that thought process, we tend to think about getting our health in order as well. Are the kids going to make it through the year “germ free”? Am I healthy enough to keep me and those around me going on the hectic schedule we call life?

In this issue we continue to give helping information about you and your family’s health. One very important part of keeping healthy is maintaining a healthy relationship with your family doctor. Cleveland Clinic gives us an informative perspective on this VIP we should all have access to (see page 16). Your Primary Care Physician (PCP) isn’t just for children, they should be your first resource in any stage of life and healthcare. Maintaining a long-term relationship with your PCP is a huge benefit in keeping you healthy.

As your thoughts turn to a seasonal change…we hope the information in this issue will continue to help you keep your healthcare goals.

Till next issue…


About What Doctors Know

Published by

What Doctors Know, LLC

Publisher and Chairman

Vicki J. Lyons, MD

Editorial and Design Director

Ran Stewart

Web and Digital Management

YourNext Services, LLC

Corporate Office
What Doctors Know
4403 Harrison Blvd. Suite 2855 Ogden, UT 84403 (801)512-0569


We're not around right now. But you can send us an email and we'll get back to you, asap.


©2020 What Doctors Know

Log in with your credentials

Forgot your details?