Atherosclerosis, or hardening of the arteries, is a major risk factor for heart attack. It occurs when cholesterol deposits and other fatty materials build up in the inner walls of a coronary artery to form a hard material known as plaque. Plaque narrows the arteries and makes them less flexible. In time, the plaque may form a blood clot. This clot can obstruct the narrowed artery restricting the flow of blood to the heart. When this happens, the heart muscle can be damaged due to a lack of vital oxygen.

Cholesterol performs a range of critical functions in our bodies. It is necessary for digesting food, making hormones and converting sunlight into vitamin D. Our cells use cholesterol to build and repair their membranes. Cholesterol is synthesized in the liver. In order to travel to the parts of the body where it is needed, it binds with a protein called high-density lipoprotein (HDL) which carries it through the bloodstream and deposits it the tissues.

If there is excess cholesterol in the body tissues, it can be transported back to the liver by low-density lipoprotein (LDL). Unfortunately, if there is two much HDL in our blood and not enough LDL, excess cholesterol deposited in the arteries can build up into harmful plaques, increasing the risk of atherosclerosis and heart attack.

A cholesterol test will reveal whether or not you have healthy levels of HDL and LDL. Common causes of too much LDL and too little HDL are obesity, lack of exercise, poor diet and smoking, all of which are responsible for a variety of health problems. Most people can help to protect themselves against heart disease by increasing their HDL levels through basic lifestyle changes.

If you are overweight, shedding the extra pounds will help you to raise your HDL levels. This is especially true if you carry the extra fat around your waistline rather than in your hips or thighs.

If you lead a sedentary lifestyle, you can increase your HDL levels by starting on a regular exercise routine. Any activity intense enough to raise your heart rate will be beneficial if you engage in it at least four times a week.

If you eat a lot of junk food, fast food or processed food, changes to your diet can help lower your LDL levels and raise your HDL levels. Try to eat more oily fish such as salmon and trout, monounsaturated fats such as olive oil and soluble fibre such as oats.

If you smoke, quitting could significantly reduce your chance of developing atherosclerosis and heart disease. Smoking is associated with lowered HDL levels, high blood pressure, and formation of blood clots in the arteries.