Featured Research

from universities, journals, and other organizations

USC Study Suggests Low Levels Of Dietary Nutrient Lutein, Found In Leafy Greens, Linked To Thickening In Neck Arteries

Date:
June 29, 2001
Source:
University Of Southern California
Summary:
Thickening of the walls of arteries in the neck may be related to low levels of a substance called lutein, commonly found in spinach, broccoli and other dark green vegetables, according to researchers at the Keck School of Medicine of the University of Southern California and the UCLA School of Medicine.

LOS ANGELES, June 18 — Thickening of the walls of arteries in the neck may be related to low levels of a substance called lutein, commonly found in spinach, broccoli and other dark green vegetables, according to researchers at the Keck School of Medicine of the University of Southern California and the UCLA School of Medicine.

Related Articles


The study on lutein and atherosclerosis—the common condition of buildup on inner artery walls that can lead to heart attacks and strokes—helps explain why fruit- and vegetable-rich diets seem to protect cardiovascular health, the researchers report in the June 19 issue of the journal Circulation. Atherosclerosis accounts for more than 1.5 million heart attacks and 600,000 strokes every year in the U.S.

"Scientific knowledge of the long-term effects of diet on cardiovascular disease is still rudimentary, but there is mounting evidence that increased intake of vegetables and fruits is protective against cardiovascular disease," says James Dwyer, Ph.D., USC professor of preventive medicine. "Unlike the use of supplements, such as beta carotene, increased intake of vegetables and fruit is also very unlikely to yield surprise adverse effects."

Dwyer continues: "The importance of our findings concerning lutein and atherosclerosis is that we may have identified one of the many components of vegetables that account for the protective effects of vegetables."

Findings suggest that increased intake of the dark green leafy vegetables, such spinach, kale and collard greens, may prevent—or at least slow—the progression of the underlying disease that leads to most heart attacks and strokes. Fortunately, such foods can easily be incorporated into a normal American diet.

"They can be eaten in raw in salads, or they can be cooked by themselves or as additions to many recipes," Dwyer says. "Cooking these greens may reduce the bioavailability of the lutein somewhat, but most of the impact on blood levels of lutein is retained after they are cooked."

Dwyer and colleagues conducted their study in three parts. They looked at the relationship between study participants’ artery wall thickness and lutein consumption, they examined cell samples from human artery walls, and they compared the arteries of mice that had eaten lutein to those of mice that had not eaten lutein.

In the first part of the study, researchers monitored 480 men and women between ages 40 and 60 participating in the Los Angeles Atherosclerosis Study. Participants had no history of heart disease or stroke. Using ultrasound technology, the researchers measured the thickness of the walls of the carotid (neck) arteries once at the beginning of the study and again 18 months later. They also measured levels of lutein in participants’ blood over the same time span.

They found that people whose blood carried the highest levels of lutein averaged only a 0.004 mm increase in the artery thickness over 18 months. In those with the lowest levels of lutein, artery wall thickness increased an average of 0.021 mm.

The second part of the study explored how lutein may protect cells in artery walls. Researchers grew layers of cells from human arteries in a lab, then exposed them to various combinations of lutein and LDL (or low-density lipoprotein, the so-called "bad" cholesterol known to promote atherosclerosis).

They found that arterial cell layers treated with lutein were less prone to starting a process of inflammation related to LDL that leads to atherosclerotic plaque. The more the inner layers of the artery wall were exposed to lutein, the more they appeared protected.

In the third portion of the study, done with mice, the team found that adding lutein to the diet resulted in the mice having significantly smaller atherosclerotic lesions compared to mice that had no lutein supplementation.

Dwyer and colleagues caution that more research must be done—from epidemiological studies to randomized trials testing specific diets—to better determine the effect of lutein from food or in supplements on human atherosclerosis and cardiovascular disease.

Lutein is in a class of compounds known as carotenoids, which are found in many foods. Other studies have suggested lutein may be important in eye health. However, another carotenoid tested in the study, beta carotene, was not found to help protect against atherosclerosis—a finding consistent with previous studies.


Story Source:

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


Cite This Page:

University Of Southern California. "USC Study Suggests Low Levels Of Dietary Nutrient Lutein, Found In Leafy Greens, Linked To Thickening In Neck Arteries." ScienceDaily. ScienceDaily, 29 June 2001. <www.sciencedaily.com/releases/2001/06/010619073645.htm>.
University Of Southern California. (2001, June 29). USC Study Suggests Low Levels Of Dietary Nutrient Lutein, Found In Leafy Greens, Linked To Thickening In Neck Arteries. ScienceDaily. Retrieved November 28, 2014 from www.sciencedaily.com/releases/2001/06/010619073645.htm
University Of Southern California. "USC Study Suggests Low Levels Of Dietary Nutrient Lutein, Found In Leafy Greens, Linked To Thickening In Neck Arteries." ScienceDaily. www.sciencedaily.com/releases/2001/06/010619073645.htm (accessed November 28, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, November 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rural India's Low-Cost Sanitary Pad Revolution

Rural India's Low-Cost Sanitary Pad Revolution

AFP (Nov. 28, 2014) — One man hopes his invention -– a machine that produces cheap sanitary pads –- will help empower Indian women. Duration: 01:51 Video provided by AFP
Powered by NewsLook.com
Research on Bats Could Help Develop Drugs Against Ebola

Research on Bats Could Help Develop Drugs Against Ebola

AFP (Nov. 28, 2014) — In Africa's only biosafety level 4 laboratory, scientists have been carrying out experiments on bats to understand how virus like Ebola are being transmitted, and how some of them resist to it. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
WHO Says Male Ebola Survivors Should Abstain From Sex

WHO Says Male Ebola Survivors Should Abstain From Sex

Newsy (Nov. 28, 2014) — WHO cites four studies that say Ebola can still be detected in semen up to 82 days after the onset of symptoms. Video provided by Newsy
Powered by NewsLook.com
Ebola Leaves Orphans Alone in Sierra Leone

Ebola Leaves Orphans Alone in Sierra Leone

AFP (Nov. 27, 2014) — The Ebola epidemic sweeping Sierra Leone is having a profound effect on the country's children, many of whom have been left without any family members to support them. Duration: 01:02 Video provided by AFP
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:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

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