Featured Research

from universities, journals, and other organizations

Vitamin D levels linked with health of blood vessels

Date:
April 3, 2011
Source:
Emory University
Summary:
A lack of vitamin D, even in generally healthy people, is linked with stiffer arteries and an inability of blood vessels to relax, researchers have found.

A lack of vitamin D, even in generally healthy people, is linked with stiffer arteries and an inability of blood vessels to relax, research from the Emory/Georgia Tech Predictive Health Institute has found.

The results add to evidence that lack of vitamin D can lead to impaired vascular health, contributing to high blood pressure and the risk of cardiovascular disease. Study participants who increased their vitamin D levels were able to improve vascular health and lower their blood pressure.

The data was presented by Ibhar Al Mheid, MD, a cardiovascular researcher at Emory University School of Medicine, at the annual American College of Cardiology meeting in New Orleans. Al Mheid is one of five finalists for the ACC's Young Investigators Award competition in physiology, pharmacology and pathology. He is working with Arshed Quyyumi, MD, professor of medicine and director of the Emory Cardiovascular Research Institute.

The 554 participants in the study were Emory or Georgia Tech employees -average age 47 and generally healthy -- who are taking part in the Center for Health Discovery and Well Being, part of the Emory/Georgia Tech Predictive Health Institute.

The average level of 25-hydroxyvitamin D (a stable form of the vitamin reflecting diet as well as production in the skin) in participants' blood was 31.8 nanograms per milliliter. In this group, 14 percent had 25-hydroxyvitamin D levels considered deficient, or less than 20 nanograms per milliliter, and 33 percent had levels considered insufficient, less than 30 nanograms per milliliter.

The researchers monitored the ability of participants' blood vessels to relax by inflating and then removing a blood pressure cuff on their arms. To allow blood to flow back into the arm, blood vessels must relax and enlarge -- a change that can be measured by ultrasound. The researchers also made other measurements of smaller blood vessels and examined the resistance to blood flow imposed by the arteries.

Even after controlling for factors such as age, weight and cholesterol, people with lower vitamin D levels still had stiffer arteries and impaired vascular function, Al Mheid says.

"We found that people with vitamin D deficiency had vascular dysfunction comparable to those with diabetes or hypertension," he says.

Throughout the body, a layer of endothelial cells lines the blood vessels, controlling whether the blood vessels constrict or relax and helping to prevent clots that lead to strokes and heart attacks.

"There is already a lot known about how vitamin D could be acting here," Al Mheid says. "It could be strengthening endothelial cells and the muscles surrounding the blood vessels. It could also be reducing the level of angiotensin, a hormone that drives increased blood pressure, or regulating inflammation."

Most Americans generally get the majority of their vitamin D from exposure to sunlight or from dietary supplements; fortified foods such as milk or cereals are a minor source. A few foods, such as oily fish, naturally contain substantial amounts of vitamin D.

Participants whose vitamin D levels increased over the next six months, either from dietary supplements or ample sun exposure, tended to improve their measures of vascular health and had lower blood pressure. Forty-two study participants with vitamin D insufficiency whose levels later went back to normal had an average drop in blood pressure of 4.6 millimeters mercury.

"This was an observational study, rather than an interventional one, and it was difficult to tease out how the people who restored their vitamin D levels got there," Al Mheid says. "We are hoping to conduct a study where we have participants take a defined regimen of vitamin D."

"With his findings showing the relationship between vitamin D deficiency and vascular dysfunction, Dr. Mheid has helped advance our understanding of the importance of Vitamin D in preventing a common health problem in aging adults," says Kenneth Brigham, MD, medical director of the Emory/Georgia Tech Center for Health Discovery and Well Being. "Additionally, ongoing health studies based on the Center's collection of health information from participants will yield more discovery as the Center continues to develop."

The Emory-Georgia Tech Predictive Health Institute is a national leader in moving the practice of medicine from a reactive, disease-focused system to a proactive health-focused system. The initiative integrates research, scholarship and education in an innovative effort aimed at revolutionizing care of people to define, preserve and prolong the health of individuals and of society.

Key areas of the Initiative include defining and measuring health using optimal biomarkers of health and understand their interrelationships, determining the best interventions to optimize health throughout an individual's or a population's lifetime.


Story Source:

The above story is based on materials provided by Emory University. Note: Materials may be edited for content and length.


Cite This Page:

Emory University. "Vitamin D levels linked with health of blood vessels." ScienceDaily. ScienceDaily, 3 April 2011. <www.sciencedaily.com/releases/2011/04/110403205232.htm>.
Emory University. (2011, April 3). Vitamin D levels linked with health of blood vessels. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2011/04/110403205232.htm
Emory University. "Vitamin D levels linked with health of blood vessels." ScienceDaily. www.sciencedaily.com/releases/2011/04/110403205232.htm (accessed April 18, 2014).

Share This



More Health & Medicine News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com
Obama: 8 Million Healthcare Signups

Obama: 8 Million Healthcare Signups

AP (Apr. 17, 2014) President Barack Obama gave a briefing Thursday announcing 8 million people have signed up under the Affordable Care Act. He blasted continued Republican efforts to repeal the law. (April 17) Video provided by AP
Powered by NewsLook.com
Is Apathy A Sign Of A Shrinking Brain?

Is Apathy A Sign Of A Shrinking Brain?

Newsy (Apr. 17, 2014) A recent study links apathetic feelings to a smaller brain. Researchers say the results indicate a need for apathy screening for at-risk seniors. Video provided by Newsy
Powered by NewsLook.com
Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins