The Legume Inflammation Feeding Experiment (LIFE): Effects of Serum Lipid Levels

Abstract

The LIFE Study was a randomized controlled crossover feeding study designed to test the effects of a low‐glycemic index diet rich in legumes on biomarkers of inflammation and insulin resistance (IR). Sixty four male subjects (35–75 yrs), who had undergone a screening colonoscopy within the past 2 years, were recruited in Central Pennsylvania, representing 4 combinations: IR (Y or N) and history of adenomatous polyps (Y or N). All subjects consumed a 4‐wk legume diet (LG; 1 ½ cups of cooked dry beans) and a 4‐wk isocaloric average American diet (AA) separated by a 3‐wk washout period. At baseline, mean (±S.D.) levels of serum total, HDL and LDL cholesterol (TC, HDL‐C and LDL‐C), and triglycerides (TG) were 200.2 (37.4), 45.1 (11.1), 128.9 (32.5), and 135.2 (72.3) mg/dL. Preliminary results show that serum TC was significantly reduced on both LG and AA diet (9.4% and 3.5%, respectively), with a significant difference between diets (P=0.0002). HDL‐C levels were reduced by 6.1% on LG diet and 1.9% on AA diet, and LDL‐C declined by 9.4% on LG diet and 1.6% on AA diet. For both HDL‐C and LDL‐C the differences between diets were significant (P=0.0138 and 0.0008, respectively). Serum TG levels were reduced significantly on both diets (LG diet, 7.2%; AA diet, 7.4%); however, the difference between diets was not significant (P=0.9620). These results suggest that a legume‐rich diet may have favorable effects on serum lipids and lipoproteins.Supported by the National Cancer Institute; partial support provided by the GCRC, PSU.