Effect of barley protein supplementation on coronary heart disease risk reduction

Objective: High animal protein weight loss diets have been associated with rises in LDL‐C. We wished to determine the effect of high barley protein intake on LDL‐C. Method: 23 hypercholesterolemic individuals (16F, 7M; 57±7y; LDL‐C, 3.90±0.21mmol/L) completed two 4‐week treatments of bread supplementation containing either 30g/d (based on a 2000 kcal diet) of barley protein (treatment group) or dairy protein (calcium caseinate placebo), in a randomized controlled crossover design. Serum lipids, body weight and blood pressure were measured biweekly on each treatment. Results: At week 4, changes expressed as the difference between baseline demonstrated no evidence that barley protein supplementation altered LDL‐C and TChol:HDL‐C (−0.09±0.11mmol/L, P=0.454 and 0.13±0.14mmol/L, P=0.364, respectively). Corresponding data for the dairy protein supplementation also showed no overall improvement (LDL‐C, 0.00±0.11mmol/L, P=0.989 and TChol:HDL‐C, 0.19±0.11mmol/L, P=0.088). Furthermore, the effect of barley protein on blood lipids was not significantly different from dairy protein (LDL‐C, P=0.836; TChol:HDL‐C, P=0.964). Conclusion: This study demonstrates that neither barley nor dairy protein appear to alter blood lipids and may be equally suitable for weight reduction diets. Funding: Natural Sciences and Engineering Research Council of Canada, Loblaws Ltd.