What is Cholesterol

Triglycerides are the chemical form in which most fat exists in food as well as in the body. They're also present in blood plasma and, in association with cholesterol, form the plasma lipids.

Triglycerides in plasma are derived from fats eaten in foods or made in the body from other energy sources like carbohydrates. Calories ingested in a meal and not used immediately by tissues are converted to triglycerides and transported to fat cells to be stored. Hormones regulate the release of triglycerides from fat tissue so they meet the body's needs for energy between meals.

Excess triglycerides in plasma is called hypertriglyceridemia. It's linked to the occurrence of coronary artery disease in some people. Elevated triglycerides may be a consequence of other disease, such as untreated diabetes mellitus. Like cholesterol, increases in triglyceride levels can be detected by plasma measurements. These measurements should be made after an overnight food and alcohol fast.

The National Cholesterol Education Program of America guidelines for triglycerides are:

Normal	Less than 150 mg/dl
Borderline-high	150 to 199 mg/dl
High	200 to 499 mg/dl
Very high	500 mg/dl or higher
These are based on fasting plasma triglyceride levels.

Changes in lifestyle habits are the main therapy for hypertriglyceridemia. These are the changes you need to make: (1) If you're overweight, cut down on calories to reach your ideal body weight. This includes all sources of calories, from fats, proteins, carbohydrates and alcohol. (2) Reduce the saturated fat and cholesterol content of your diet. (3) Be physically active for 30 minutes on most days each week. (4) People with high triglycerides may need to substitute monounsaturated and polyunsaturated fats such as canola oil, olive oil or liquid margarine instead of carbohydrates for saturated fats. Carbohydrates raise triglyceride levels and decrease HDL ("good") cholesterol. (6) Substitute fish high in omega-3 fatty acids instead of meats that are high in saturated fat like hamburger. Fatty fish like mackerel, lake trout, herring, sardines, albacore tuna and salmon are high in omega-3 fatty acids (Safeer and Ugalat 2002).

Because other risk factors for coronary artery disease multiply the hazard from hyperlipidemia, control high blood pressure and avoid cigarette smoking. If drugs are used to treat hypertriglyceridemia, dietary management is still important. Patients should follow the specific plans laid out by their physicians and nutritionists.

Primary and secondary prevention trials for coronary heart disease in hyperlipidaemic or so-called 'normolipidaemic' patients with drugs affecting lipid metabolism have clearly confirmed that even slight alterations in lipoprotein metabolism are major risk factors for coronary heart disease. There are four classes of available lipid-regulating drugs: HMG-CoA reductase inhibitors (statins), bile acid sequestrants (resins), peroxisome proliferator-activated receptor-alpha activators (fibrates) and nicotinic acid. All four will be discussed in this review. Clinical trials have shown that drugs improving lipid metabolism reduce coronary heart disease relative risk from 24% (secondary prevention) to 37% (primary prevention) and the absolute risk from 2% (primary prevention) to 8.5% (secondary prevention) (Duriez 2001).

References

· Duriez P. Current practice in the treatment of hyperlipidaemias. Expert Opin Pharmacother. 2001;2:1777-1794.

· Safeer RS, Ugalat PS. Cholesterol treatment guidelines update. Am Fam Physician. 2002 1;65:871-880.