Medical Nutrition Therapy for Disorders of Lipid Metabolism
Manual of Clinical Nutrition Management C- 46 Copyright © 2 013 Compass Group, Inc.
Nuts: Nuts may enhance the cardioprotective dietary pattern because of their beneficial fatty acid profile as
well as other favorable nutritional components (5,43). The daily consumption of 50 to 113 g (½ to 1 cups) of nuts
with a diet low in saturated fat and cholesterol decreased total cholesterol by 4% to 21% and LDL cholesterol
by 6% to 29% when weight was not gained (Grade II) (5,45,46). Nuts (walnuts, almonds, peanuts, macadamia,
pistachios, and pecans) may be isocalorically incorporated into a cardioprotective dietary pattern low in
saturated fat and cholesterol (5). Consuming 5 oz/week of nuts is associated with a reduced risk of CHD (5,45,46).
Stanol and sterol ester–containing foods: Plant sterols occur naturally and are isolated from soybean oils (3).
Plant sterols are generally esterified, forming sterol esters, to increase solubility; in some cases, plant sterols
are saturated to form stanol esters (3). Esterified forms of plant sterols and stanols are potent
hypercholesterolemic agents, and the daily consumption of 2 to 3 g (in the form of margarine, lowfat yogurt,
orange juice, breads, and cereals) lowers total cholesterol concentrations in a dose-dependent manner by 4% to
11% and LDL cholesterol concentrations by 7% to 15% (Grade II) (5,47,48). The efficacy of the two forms, plant
stanol esters and plant sterol esters, is comparable (Grade II) (5, 47, 48). In addition, non-esterified forms of sterols
and stanols are equally effective (Grade III) (5,49). The total cholesterol and LDL-cholesterol lowering effects of
stanols and sterols are evident even when sterols and stanols are consumed as part of a cholesterol-lowering
diet (Grade I) (5,47,48). For patients receiving statin therapy, plant stanols further reduce LDL cholesterol and total
cholesterol (Grade III) (5). A limited effect of plant stanols and sterols on HDL cholesterol and triglycerides has
been reported. If consistent with patient preference and not contraindicated by risks or harms, then plant
sterol ester– and stanol ester–enriched foods may be consumed two or three times per day, for a total of 2 or 3
g/day, in addition to a cardioprotective diet to further lower total cholesterol and LDL cholesterol levels (Grade I)
(5). For maximal effectiveness, foods containing plant sterols and stanols (spreads, juices, and yogurts) should
be eaten with other foods (5). To prevent weight gain, isocalorically substitute stanol- and sterol-enriched foods
for other foods (5). Plant stanols and sterols are effective in people who take statin drugs. Plant sterol and
stanol products should not be used in individuals with sitosterolemia (5).
Other Diet Approaches
Very-low-fat, high-carbohydrate (VLFHC) diets: Very-low-fat (up to 15% of total energy), high-carbohydrate
(greater than or equal to 60% of total energy) diets have been implemented with patients who are not
responsive to diets with more moderate fat intake (eg, 25% to 30%). Progression of coronary atherosclerosis
was delayed among patients who consumed a VLFHC diet and engaged in regular exercise (50,51). Replacing
both saturated fat and unsaturated fat with carbohydrates can lower total cholesterol and LDL cholesterol
levels. In addition, carbohydrate increases VLDL concentrations by adding triglycerides to VLDL particles, a
characteristic unfavorable to individuals who have preestablished characteristics of metabolic syndrome. A
VLFHC diet also decreases HDL cholesterol levels (1). However, the VLFHC diet–induced lowering of HDL
cholesterol concentrations has not been associated with the increased risk of atherosclerosis seen with low
HDL cholesterol levels that are associated with a high-fat diet (52). Decreases in total cholesterol and HDL
cholesterol levels with VLFCH diet plans may result in a more favorable total cholesterol–to-HDL ratio. This
finding was observed in participants in the Lifestyle Heart Trial who demonstrated angiographic regression of
their CHD while also demonstrating diet-induced lowering of HDL cholesterol levels (51).
The VLFCH diet plans include the Pritikin program and the Ornish meal plans (50,51). These meal plans limit
total fat intake to less than 10% of total energy and encourage the consumption of whole grains, fruits, and
vegetables in addition to increased physical activity and reduced stress. In certain individuals under a
physician’s supervision, very-low-fat diets may lead to weight loss and improved lipid profiles. However, these
diets are not recommended by the AHA, as previously mentioned, especially for persons who exhibit
characteristics of metabolic syndrome or who have hypertriglyceridemia (3). See “Total fat and saturated fatty
acids” earlier in this section.
Mediterranean diet: The traditional Mediterranean diet has been investigated based on favorable effects on
the lipid profile and decreased CHD risk in persons who live in Mediterranean countries. The Mediterranean
diet is a plant-based diet that emphasizes fruits, vegetables, breads and other cereal grains, potatoes, beans,
nuts, and seeds (53). Olive oil is the principal fat source. Cheese and yogurt are the key dairy products
consumed daily. Fish, poultry, and eggs are consumed in moderate amounts. Desserts consist of fresh fruit, and
concentrated sugars are eaten only a few times per week. Little red meat is eaten, and moderate amounts of red
wine can be consumed with meals (53). Total fat content of the diet ranges from 25% to 35% of total energy, and
saturated fat contributes less than 8% of total energy. Few studies have examined the Mediterranean diet plan.
In one study, recurrent myocardial infarction, all cardiovascular events, and cardiac and other deaths were
reduced by 70% in the group consuming a Mediterranean diet (54). Further research is needed to investigate
the impact of this diet plan on cholesterol lowering and to determine if it is the specific dietary components (eg,