Homocysteine, clogged arteries
New Heart Prescription: B VitaminsBy Dr. Gifford Jones
Why do some people die from heart attacks when their blood cholesterol is normal? They’ve never smoked a cigarette, are thin a rail, exercise regularly, take vitamins E and C and don’t suffer from diabetes, hypertension or other cardiac risk factors. Evidence is mounting that the culprit may be increased amounts of homocysteine in the blood. Ah, what sweet revenge for Dr. Kilmer McCully.
In 1968 Dr. Kilmer McCully was a pathologist at Harvard’s prestigious Massachusetts General Hospital. He was performing an autopsy on a two month old boy who had died of a rare genetic disease, “homocystinuria”.
This disease causes high levels of homocysteine to accumulate in the blood. McCully noted that the infant’s arteries were hardened and clogged. The changes were identical to older patients with advanced vascular disease.
Dr. McCully made a reasonable assumption that homocysteine might be related to coronary heart disease. But he was young and his older colleagues scoffed at his theory. For sticking to his guns he was finally asked to find a position elsewhere. So much for my own Alma Mater’s open-mindedness!
Now 14 years later several world studies have confirmed there is a possible link between increased levels of homocysteine and vascular disease.
Homocysteine is a waste product of protein metabolism. It’s the task of three B vitamins, B6, B12 and especially folic acid, to remove homocysteine from the blood.
The evidence linking homocysteine to vascular disease is not conclusive. But a study conducted in 9 European countries should make everyone take notice.
The results showed that elevated blood levels of homocysteine can raise the risk of heart disease as much as smoking a pack of cigarettes a day. Or having a high blood pressure of 160/95. Or an elevated blood cholesterol. And the effect was the same for men and women.
A recent report in the Journal of the American Medical Association revealed that high homocysteine levels are not only associated with coronary heart disease.
For instance, 9 of 11 studies showed that increased homocysteine was related to higher incidence of stroke. And all 9 studies found a relationship between increased homocysteine and arterial disease of the legs.
The Physicians Health Study of 300 doctors added more evidence. Physicians who had suffered a heart attack were compared with those who had escaped this problem.
The likelihood of having a coronary attack was found to be over three times greater among physicians with the highest levels of homocysteine.
Other evidence abounds. For instance, the Nutrition Canada Survey found that Canadians with the lowest levels of folic acid in the blood had a 69 percent greater risk of death from CHD.
A study in the journal Circulation even found a link between high homocysteine and CHD in young women. A group in which heart disease is rare.
The scary conclusion? Those who had the highest elevated evels of homocysteine had double the risk of heart disease.
It’s not certain how high blood levels of homocysteine trigger heart disease. But it’s believed that homocysteine injures the inner endothelial lining of arteries. This sets the stage for both clogging of the artery and increased risk of blood clot.
It’s still too early to know whether this theory will stand the test of time.
So what should we all do? One could wait for more proof. But being tardy about getting sufficient amounts of B vitamins might result in a needless coronary attack.
One in five adults has homocysteine levels high enough to increase the risk of heart disease. It’s also estimated that 88 percent of North Americans consume less than the recommended 400 micrograms of folic acid.
The most sensible approach is to ensure an adequate dietary intake of B vitamins. Folic acid is present in green leafy vegetables, fruits, wheat germ, brewer’s yeast, dried beans, peas and liver. Vitamin B6 is also present in green leafy vegetables, along with fish, meat, poultry, whole grain cereals, nuts. For B12 you need dairy products, eggs, meat and fish. Remember that several servings of fruit and vegetables daily also helps to reduce the risk of some types of cancer and other chronic diseases
If you have a diet deficient in these vitamins it’s wise to take a multivitamin supplement. Dr. Meir Stampfer, a world authority on vitamins, believes the dosages found in typical multivitamins are acceptable.(0) Reader Feedback | Email Article | Email Us | Print friendly
Dr. Gifford Jones Bio
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W. Gifford-Jones M.D is the pen name of Dr. Ken Walker graduate of The Harvard Medical School. He’s been a ship’s surgeon, hotel physician and family doctor and later trained in surgery at McGill in Montreal, University of Rochester N.Y. and Harvard. His medical column is published by 60 Canadian newspapers and several in the U.S. He is the author of seven books. Dr. Walker has a medical practice in Toronto. His Web site is: http://www.mydoctor.ca/gifford-jones