Egg consumption as part of an energy-restricted high-protein diet improves blood lipid and blood glucose profiles in individuals with type 2 diabetes

The role of dietary cholesterol in people with diabetes has been little studied. We investigated the effect of a hypoenergetic high-protein high-cholesterol (HPHchol) diet compared to a similar amount of animal protein (high-protein low-cholesterol, HPLchol) on plasma lipids, glycaemic control and cardiovascular risk markers in individuals with type 2 diabetes. A total of sixty-five participants with type 2 diabetes or impaired glucose tolerance (age 544 (sd 82)years; BMI 341 (sd 48)kg/m²; LDL-cholesterol (LDL-C) 267 (sd 010)mmol/l) were randomised to either HPHchol or HPLchol. Both hypoenergetic dietary interventions (6-7MJ; 14-17 Mcal) and total carbohydrate:protein:fat ratio of 40:30:30% were similar but differed in cholesterol content (HPHchol, 590mg cholesterol; HPLchol, 213mg cholesterol). HPHchol participants consumed two eggs per d, whereas HPHchol participants replaced the eggs with 100g of lean animal protein. After 12 weeks, weight loss was 60 (sd 04)kg (P<0001). LDL-C and homocysteine remained unchanged. All the subjects reduced total cholesterol (03 (sd 01)mmol/l, P<0001), TAG (04 (sd 01)mmol/l, P<0001), non-HDL-cholesterol (HDL-C, 04 (sd 01)mmol/l, P<0001), apo-B (004 (sd 002)mmol/l, P<001), HbA1c (06 (sd 01)%, P<0001), fasting blood glucose (05 (sd 02)mmol/l, P<001), fasting insulin (17 (sd 07)mIU/l, P<001), systolic blood pressure (76 (sd 17)mmHg, P<0001) and diastolic blood pressure (46 (sd 10)mmHg; P<0001). Significance was not altered by diet, sex, medication or amount of weight loss. HDL-C increased on HPHchol (+002 (sd 002)mmol/l) and decreased on HPLchol (007 (sd 003)mmol/l, P<005). Plasma folate and lutein increased more on HPHchol (P<005). These results suggest that a high-protein energy-restricted diet high in cholesterol from eggs improved glycaemic and lipid profiles, blood pressure and apo-B in individuals with type 2 diabetes.