What You Need to Know
Cholesterol is a waxy substance, produced from the fats you eat, that your body uses as the building block for cell walls, hormones and a digestive fluid called bile acid. There are two main types: “bad” LDLs, which form the basis of artery-clogging plaque, and “good” HDLs, which carry LDLs to the liver for elimination.
How It Accumulates
Central fat (around the stomach), a diet high in saturated fat and lack of activity can all prompt your liver to churn out more and more LDLs. A diet low in monounsaturated fat and a life devoid of exercise can deplete helpful HDLs, as can smoking and diabetes.
There are no physical clues as to the levels of cholesterol in your bloodstream; only blood tests can reveal them. A standard test, performed by your doctor, measures total cholesterol, LDLs and HDLs, in millimoles per litre of blood.
Standard Medical Care
More than a billion dollars is spent on cholesterol-lowering statin drugs in Canada every year, a number that is expected to grow as researchers advise prescribing these effective drugs to a wider audience. Evidence grows that statins, while lowering cholesterol, also act in additional ways to improve arterial health and reduce cardiac disease. The next goal is better HDL-raising drugs. Some doctors prescribe niacin supplements to bolster HDLs.
What You Can Do
Most of us put ourselves at risk—by eating an unhealthy diet, by smoking, by being overweight or by failing to exercise sufficiently.
Too much saturated fat in the diet equals too much cholesterol in the bloodstream equals clogged arteries and heart attacks. Despite the fact that heart disease has been one of the leading causes of death in Canada for the last 100 years, nobody wanted to hear that the delicious things in life—butter, cheese, cakes and ice cream—just might spell doom.
The story centres on Dr. Ancel Keys, a researcher at the University of Minnesota. During World War II, Dr. Keys produced “K” rations—nutritious brown-boxed meals for the U.S. military. In the early 1950s, he noted that well-fed American businessmen had soaring rates of heart disease, while rates among people living through food shortages in post-war Europe declined.
After studying men in seven countries—Finland, Greece, Yugoslavia, Italy, the Netherlands, Japan and the United States—and comparing their blood cholesterol levels, intake of saturated fats and cardiovascular disease rates, Dr. Keys concluded that a “strong association” existed between saturated fats and heart health. Dr. Keys, who was featured on the cover of Time magazine, recommended cutting saturated fat and eating more polyunsaturated fats (such as sunflower oil) to lower total cholesterol levels. Less total cholesterol, he reasoned, would lead to fewer heart attack deaths. It was the basis for the 1950s heart-healthy “prudent diet,” designed to improve cholesterol levels and ward off heart disease. But the cholesterol story wasn’t that simple.
Fast-forward to the 21st century. Cholesterol isn’t necessarily a villain. Your liver (and your intestines and even your skin) manufactures this soft, waxy stuff every day to help your body to build cell membranes and produce sex hormones, vitamin D and fat-digesting bile acids. The raw material for your body’s cholesterol is dietary fat.
The real key to heart-healthy cholesterol levels, experts now say, is a balance between two basic types: “lousy” or “bad” low-density lipoproteins (LDLs) and “healthy” or “good” high-density lipoproteins (HDLs). The latest news is that heart experts are finding that the higher your HDLs and the lower your LDLs—essentially, the closer you can come to the “natural” cholesterol balance observed in hunter-gatherer societies—the lower your risk of blocked coronary arteries and heart attack.