Fats, Dietary Health Article

Treating high lipids

If a person's blood lipid levels are high, dietary treatment is often initiated to lower the low density lipoprotein fraction and total blood cholesterol levels. Current American Heart Association recommendations include reducing saturated fat to less than 7% of calories; limiting cholesterol to < 200; losing weight if appropriate; and increasing soluble fiber to 0.35–0.88 oz (10–25g) per day. High-density lipoprotein (HDL) levels, also referred to as the good cholesterol, is related more to genetic and other factors than to diet, although moderate alcohol consumption raises HDL.

Some people also have high plasma triglyceride (TG) levels, which accumulating evidence is showing may be an important heart disease risk factor. Dietary guidelines involve low simple sugars, low-saturated fat diets, restricted alcohol and weight loss if indicated. Drug therapy is often initiated.

Results

A diet containing 30% or less fat is considered compatible with good health. Diets with dietary fat intakes below 15% can negatively affect blood lipids in some people. For people with high blood lipid levels, dietary fat management goals involve moving the total cholesterol and LDL levels to normal. However, because diet modification lowers serum cholesterol levels by about 10–15%, patients whose blood levels remain high often seek drug therapy.

Health care team roles

• Registered dietitians are often sought out by patients and health professionals to assess fat intake and instruct on diet modifications, and for those seeking weight loss through dietary fat restriction.
• Nursing and allied health professionals can provide health histories and check laboratory test results for potential treatment. The American Heart Association provides dietary guidelines and patient education materials. All health professionals can play important roles in educating the public about dietary fat.

KEY TERMS

Atherosclerosis—Sclerosis or hardening and thickening of the arterial wall, causing a loss of elasticity.

Coronary heart disease (CHD)—A disease involving the blood vessels surrounding the heart; also called coronary artery disease (CAD).

High-density lipoprotein (HDL)—A plasma lipoprotein containing mostly protein and less cholesterol and triglyceride; high levels of HDL lower CHD risk.

Low-density lipoprotein (LDL)—The major cholesterol carrier in the blood, with high levels associated with increased coronary heart disease risk.

Fatty acid—Fatty acids are a group of carbon chains that make up fat. The body requires some, called essential fatty acids, to form membranes and synthesize important compounds.

Lipids—A group of compounds that include fats, oils and related compounds found in foods and the human body.

Omega-3 fatty acids—Named because their first double bond occurs at the third carbon from the methyl end, the three omega-3s (EPA, LNA and DHA) are believed to benefit inflammatory diseases.

Monounsaturated fatty acid (MUFA)—A fatty acid containing one double bond, which lowers plasma cholesterol when replacing SFAs and is believed to be safer than polyunsaturated fats.

Polyunsaturated fatty acid (PUFA)—A fatty acid that is liquid at room temperature, lowers plasma cholesterol when replacing SFAs, but too much can promote cardiovascular disease

Saturated fatty acid (SFA)—A fatty acid that has no double bonds, is solid at room temperature, and raises blood cholesterol levels.

BOOKS

Mahan, L. K., Escot-Stump, S. Krause's Food, Nutrition, & Diet Therapy. Philadelphia: W. B. Saunders Company, 1996.

ORGANIZATIONS

American Heart Association. National Center, 7272 Greenville Ave., Dallas, TX 75231. 1-800-AHA-USA1. <www.americanheart.org>.

Linda Richards, R.D., C.H.E.S.