NEW YORK, Nov. 13 Leafy green vegetables may help protect heart tissue from the injury caused by a heart attack, U.S. researchers say.
The findings, published in the Proceedings of the National Academy of Sciences, suggest nitrite -- found in celery, beets and greens -- may be the secret ingredient of the heart-healthy Mediterranean diet. Additionally, about 10 percent of the nitrates found in cured meats like bacon change into nitrites in the body.
"Recent studies show that administering nitrite to animals, either intravenously or orally, can greatly limit the damage caused by a heart attack and the stress to tissue that follows due to reperfusion -- the return of blood to oxygen-starved heart muscle," senior author Dr. David Lefer, of the Albert Einstein College of Medicine in New York, said in a statement.
"Europeans' copious consumption of vegetables puts them far ahead of us in terms of nitrite and nitrate intake -- this large intake of nitrite and nitrate ... could certainly help explain why the Mediterranean diet is heart-healthy despite its relatively high-fat content."
Examination of the hearts of mice after reperfusion revealed the hearts of the nitrite-supplemented mice were richer in nitrite and heart-muscle damage was reduced by 48 percent compared with the controls.
Nitrates sometimes degrade into possibly carcinogenic nitrosamines. In large doses, nitrates are lethal.
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