Effect of a Dietary Portfolio of Cholesterol-Lowering Foods Given at 2 Levels of Intensity of Dietary Advice on Serum Lipids in Hyperlipidemia: A Randomized Controlled Trial
What is the impact of a dietary portfolio administered at two levels of intensity on percentage change in low-density lipoprotein cholesterol (LDL-C) among participants following self-selected diets?
This was a parallel-design study of 351 participants with hyperlipidemia from four participating academic centers across Canada in which patients were randomized to one of three treatments lasting 6 months. Participants received dietary advice for 6 months on either a low−saturated fat therapeutic diet (control) or a dietary portfolio, for which counseling was delivered at different frequencies, that emphasized dietary incorporation of plant sterols, soy protein, viscous fibers, and nuts. Routine dietary portfolio involved two clinic visits over 6 months, and intensive dietary portfolio involved seven clinic visits over 6 months.
In the modified intention-to-treat analysis of 345 participants, the overall attrition rate was not significantly different between treatments (18% for intensive dietary portfolio, 23% for routine dietary portfolio, and 26% for control). The LDL-C reductions from an overall mean of 171 mg/dl were −13.8% (p < 0.001) for the intensive dietary portfolio; −13.1% (p < 0.001) for the routine dietary portfolio; and −3.0% (p = 0.06) for the control diet. Percentage LDL-C reductions for each dietary portfolio were significantly more than the control diet (p < 0.001, respectively). The two dietary portfolio interventions did not differ significantly (p = 0.66). Among participants randomized to one of the dietary portfolio interventions, percentage reduction in LDL-C on the dietary portfolio was associated with dietary adherence (r = −0.34, n = 157, p < 0.001).
The authors concluded that use of the dietary portfolio compared with the low−saturated fat dietary advice resulted in greater LDL-C lowering during 6 months of follow-up.
This study lends strong support to supplementing the low-fat diet with plant stanols, sources of fiber, and soy protein for lowering LDL-C. Several studies have shown that diets high in fiber provide many nonlipid benefits including anti-inflammatory and lowering of the blood pressure. It would be interesting to see to what degree the dietary portfolio adds to the effects of the Mediterranean diet that was shown in the Lyon Diet Heart Study to decrease cardiac death and nonfatal myocardial infarction up to 4 years after a first infarction.
Keywords: Myocardial Infarction, Infarction, Hyperlipidemias, Phytosterols, Vascular Diseases, Canada, Soybean Proteins, Blood Pressure, Diet, Mediterranean, Cholesterol, Dietary Supplements, Isoflavones, Tooth Attrition, Nuts, Diet, Fat-Restricted, Dietary Fiber
< Back to Listings