How to lower unwanted triglycerides

By Injil Abu Bakar

NEW YORK (JP): What are triglycerides? Triglycerides are simply fat: all the fats you eat are triglycerides. They are transported through the bloodstream as a source of energy for the body.

Fatty acids from triglycerides are used for muscle work or stored in body fat (for future energy). Just as with excess cholesterol or glucose in the blood, having elevated levels of triglycerides can be associated with health problems.

Triglycerides should be measured after fasting (nothing to eat or drink except plain water) for 12 to 14 hours. Triglycerides vary a lot depending on what you have recently had to eat and drink. In America, National Cholesterol Education Program cutoff points for fasting triglyceride levels in adults are shown in the following table.

Acceptable Less than 200 Borderline high 200 - 400 High 400 - 1,000 Very high Greater than 1,000

Many authorities believe, however, that a value lower than 150 is preferable, especially in people at high risk for heart disease (including all diabetic patients) and in women (because levels of triglycerides and HDL (high density lipoprotein)- cholesterol appear to be especially strong risk factors in women). There is even some evidence that risk of coronary heart disease (CHD) can increase at a triglyceride level of 100.

Risks

Many people find the health risks of blood triglycerides to be confusing, which is understandable. The relation between elevated blood triglycerides and risk for heart disease is not as straightforward as the risk conferred by elevated LDL (low density lipoprotein)-cholesterol, which is the most powerful lipid risk factor for CHD.

As the LDL-cholesterol level rises, CHD risk rises accordingly; excess LDL particles can enter the artery wall and deposit lipids there to contribute to atherosclerosis. HDL particles may remove some of the lipids from the artery wall -- thus, higher HDL-cholesterol levels are better.

Triglycerides are delivered to cells by two major particles: VLDL (very low density lipoprotein) particles, which are manufactured in the liver, and chylomicrons, which are manufactured in the intestine from fats that have just been ingested.

Like LDL, VLDL particles may deposit lipids in the artery wall, but chylomicrons are probably too large to enter the wall (although the smaller chylomicron remnants may). In a healthy person, chylomicrons are absent from the blood after fasting. Chylomicrons are usually found in the blood after fasting when the total triglyceride value is 300 or higher.

At very high triglyceride levels, the blood may actually have a milky appearance from the presence of chylomicrons. Triglyceride values greater than 1,000 confer risk for acute pancreatitis, a painful inflammation of the pancreas that can be life threatening and that requires immediate medical intervention. Triglyceride values of 400 to 500 are unpredictable and can quickly skyrocket to 1,000 or higher.

Thus, it is triglyceride levels in the range of 200 (or likely even lower) to 400 or 500 are of great interest in heart disease risk. These levels of elevated triglycerides usually represent elevated VLDL. Increased risk for CHD related to elevated VLDL triglycerides is especially likely in certain settings, for example, in patients who are obese or who have diabetes mellitus.

Low HDL-cholesterol often accompanies elevated triglycerides and the combination increases the risk for CHD even more. In addition, low HDL-cholesterol and elevated triglycerides are part of a cluster of risk factors called syndrome X, cardiovascular metabolic syndrome, or insulin resistance syndrome.

Other components of the syndrome include high blood pressure, resistance to insulin-stimulated glucose uptake, glucose intolerance, and compensatory hyperinsulinemia. Overweight (in particular central obesity, or the "apple shape") and a sedentary lifestyle predispose to this syndrome that increases risk for CHD and for the development of type-2 diabetes mellitus. Elevation of LDL-cholesterol (hypercholesterolemia) may or may not be present in syndrome X. Risk for CHD is particularly high when there is the triad of elevated LDL-cholesterol, low HDL-cholesterol and elevated VLDL triglycerides.

Causes

While elevated triglycerides have a genetic component in many cases, lifestyle choices -- in particular, consumption of excess calories and physical inactivity leading to overweight or obesity -- frequently play a key role in the disorder.

In some cases the elevated triglycerides may be due to an underlying medical condition or use of certain drugs. Your physician can help you determine possible causes. A dietitian can help you change your eating pattern to control the first four possible causes listed below. * Diabetes mellitus * Pregnancy * Hypothyroidism * Chronic renal failure * Pancreatitis * Bulimia * Cushing's syndrome * Hypopituitarism * Monoclonal gammopathy * Glycogen storage disease * Lipodystrophy * Acute intermittent porphyria * Systemic lupus erythematosus * Beta-blocker, diuretic use * Estrogen use (contraceptive or hormone replacement therapy) * Glucocorticoid use * Isotretinoin use * Protease inhibitor use * Tamoxifen use

Lowering Triglycerides

Along with control of underlying medical conditions or drug use, several lifestyle modifications are the primary treatment for elevated triglycerides. * Controlling body weight * Restricting alcohol use (in some patients) * Increasing the ratio of monounsaturated fat to saturated fat and increasing the proportion of carbohydrate obtained from complex rather than simple carbohydrates * Eating a diet low in saturated fat and cholesterol * Exercising regularly * Stopping smoking (for general cardiovascular health).

For overweight individuals, weight loss is usually very effective in lowering triglycerides. Recent research by Lynne Scott and others is showing that a diet high in monounsaturated fat, moderately high in protein, and moderately low in carbohydrate (especially simple carbohydrate) lowers triglycerides.

Some patients may need lipid-regulating drug therapy in addition to lifestyle modification. Niacin, fibrates, and statins can all effectively lower blood triglycerides; no such agent, however, should be taken without a physician's prescription and supervision.

-- The writer is a general practitioner based in Denpasar, Bali and can be contacted at injila@hotmail.com