Objective: Compared to vegetable oils in their unmodified state, partially-hydrogenated fat is associated with less favorable effects on cardiovascular disease (CVD) risk factors. Acceptable alternatives must be adjudicated. Our objective was to assess the effect of a recent commercial fat substitution, corn oil for partially-hydrogenated soybean oil.
Methods: Using a double-blind cross-over design, 30 postmenopausal women >or=50 years with LDL-cholesterol concentrations >or=120 mg/dL were randomly assigned to each of two 35-day phases; all food and beverage was provided to maintain body weight. Corn or partially-hydrogenated soybean oil was incorporated throughout the diet and contributed two-thirds of fat. Primary outcomes included fasting and non-fasting lipid, lipoprotein, apolipoprotein, and fasting high sensitivity C-reactive protein (hsCRP) concentrations; secondary outcomes included fasting small dense LDL (sdLDL)-cholesterol, remnant lipoprotein cholesterol (RemLC), glycated albumin, adiponectin and immunoreactive insulin concentrations, and endogenous cholesteryl ester transfer protein (CETP) and lecithin:cholesterol acyl transferase (LCAT) activities.
Results: Relative to the partially-hydrogenated soybean oil enriched diet, the corn oil enriched diet resulted in lower fasting total cholesterol (7%; P<0.0001), LDL-cholesterol (10%; P<0.0001), VLDL-cholesterol (7%; P=0.052), apo B (9%; P<0.0001), lipoprotein (a) [Lp(a)] (5%; P=0.024), sdLDL-cholesterol (17%; P=0.001), and RemLC (20%; P=0.007) concentrations, and no significant effect on the other outcomes. Changes in postprandial (4-h post-meal) lipid, lipoprotein and apolipoprotein concentrations were similar to the fasting state.
Conclusion: The replacement of partially-hydrogenated soybean oil with corn oil favorably affects a range of CVD risk factors and is an appropriate option to decrease cardiovascular disease risk factors in moderately hypercholesterolemic individuals.
Trial registration: ClinicalTrials.gov NCT00175071.