Predicting and preventing atherosclerosis

Scientists are now discovering a possible mechanism for the chemical changes that precede atherosclerosis, the underlying hidden pathway to heart disease. Here's what you need to know about predicting and preventing atherosclerosis.

This research into atherosclerosis involves linking various forms of environmental assault on the body — both factors you can control, such as your diet, any drugs you take or smoking, and those you can't — environmental pollution or radiation, for example.

Interest is focused on oxidative stress — cell damage that roving molecular rogues called free radicals cause. Your body produces large amounts of potentially destructive free radical oxygen molecules through such round-the-clock processes as breathing and digestion.At any given moment, your bloodstream is filled with free radicals, whose destructive power stems from each having a single, unpaired electron. The problem is that thefree radicalsrequire another electron to balance themselves out. So these unstable particles "steal" electrons from other molecules in the body. This damages genes, proteins and lipoproteins — and raises your risk of heart disease, cancer and other diseases.

Normally, your body's own defences — including antioxidants from the foods you eat — quickly mop up rampaging free radicals. If, however, you smoke, are overweight, don't exercise enough, get too anxious, have metabolic syndrome or opt for fast food such as chips and cola too often, this cleanup doesn't happen. And it also doesn't happen if your cells are pumping out extra free radicals while neutralizing the effects of ultraviolet light, pollution, tobacco smoke, too much alcohol or even too many drugs — whether they're of the prescription, over-the-counter or illegal variety.

When your body's natural antioxidant defences become overwhelmed, you've got oxidative stress.Researchers now believe that oxidative stress is a key turning point for heart health; they think it's the condition that switches atherosclerosis from "off" to "on."

The decisive moment seems to be when LDL particles are oxidized. It is then that their cargo of cholesterol becomes more deadly and more likely to end up clogging arterial walls.To your immune system, oxidized LDLs, which researchers call LDL-ox, look like grotesque invaders.

Immune cells known as macrophages trap them and in the process they become the fat-filled foam cells that form the foundation for plaque. LDL-ox also seems to make plaques grow larger and burst, leading to heart-stopping blood clots. High levels of LDL-ox can double your heart attack risk.

Japanese researchers have found that people with high levels of oxidized LDL are more likely to suffer from severe heart disease: patients who had a heart attack had levels of oxidized LDL four times higher than those in a healthy control group.

Many agree that the evidence suggests that oxidized cholesterol may accelerate the furring of the arteries that can lead to a heart attack. Luckily, eating a diet rich in fruit and vegetables can prevent oxidation to a degree since these foods are full of antioxidant nutrients.

Your LDLs are more vulnerable to oxidation. As a result, you're more susceptible to heart disease. Even if your LDL levels are in the normal range, having metabolic syndrome raises the odds of your LDLs being the small, dense type that free radicals easily damage.

Sophisticated blood tests can tell you if you have these super-dangerous LDLs, but there's a simpler way to check. If blood test results show that you have low HDLs plus high triglycerides, you probably have small, dense LDLs as well.

Don't let this information about predicting and preventing atherosclerosis scare you. Instead, use it to start a conversation with your doctor about atherosclerosis.