Nitric Oxide

and lipoprotein (a)—damage the endothelium. And a damaged endothelium doesn’t make enough NO, which results in more damage in an increasingly dangerous spiral. “But we can restore endothelial health and the lining of the vessel through exercise and nutrition,”Dr. Cooke says. Certain nutritional supplements (like arginine) and drugs used to treat heart disease (like aspirin and statins) can also help,

By the Numbers

if doctors could measure endothelial function—how blood vessels behave—they would have a good indication of your nitric oxide production, and in fact, your overall risk for coronary heart disease (CHD). Measuring endothelial function is like asking your arteries, “How’s it going?” If the answer is “well,” your arteries are happy with the composition of the blood and are probably relatively free of plaque.

Doctors can measure endothelial function in various ways, most of which involve using ultrasound to measure changes in the diameter of certain arteries. This testing is usually used for research purposes only, But soon there may be a way to test endothelial firnction right in the doctor’s office. In late 2000 the FDA approved a new, hotinvasive instrument called CVProfilor DO-2020 that can measure the elasticity of your arteries, an indication of NO production. Normal ranges vary depending on your age and sex. The Lest isn’t, in routine use yet, but that day may be coming.

How the Plan Can Help

The Plan is designed to promote the overall health of your heart and blood vessels, not just lower your cholesterol. There are several ways it contributes to better endothelial function. First, it. calls for plenty of foods that contain the amino acid arginine, from which NO is produced. These foods include beans, soy, almonds, walnuts, oats, and such cold-water fish as salmon, tuna, and mackerel,

Also, endothelial function is highly sensitive to saturated fat, Just one meal high in saturated fat can temporarily cut endothelial funetion almost in half. And of course you’ll cut your intake of saturated fat on the Plan.

Finally, exercise plays a tremendous role in the production of NO and the health of the endothelium, Dr, Cooke says, because the increased blood flow that occurs during exercise encourages the endothelium to make more NO. Over the long term, if you exercise every day, your endothelial cells not only release more NO but also make more of the enzyme that converts arginine into NO. It’s like expanding the size of the NO factory. “That’s why the coronary arteries of long-distance runners have twice the capacity to relax and expand as those of same-aged couch potatoes,” Dr. Cooke says.