The effects of some dietary changes upon the concentrations of serum lipids in rats

Abstract

1. The responses of serum lipids of weanling and adult male rats to different diets have been examined. Total cholesterol, phospholipids and triglycerides were measured. The proteins used in the diets were casein and wheat gluten, the carbohydrates were starch and sucrose, and the main lipid source was groundnut oil supplemented with either gluten oil or maize oil.2. In general, the type of carbohydrate did not influence the experimental results, whereas the type of protein had a marked effect. Compared with casein, gluten caused an increase in concentration of serum triglycerides, phospholipids and cholesterol in weanling rats, but there was no change in adult animals. Much of this ‘gluten effect’ in weanlings was not ob- served when the diet was supplemented with 0.7% L-lysine hydrochloride.3. When 1% cholesterol was added to the gluten diets, the serum cholesterol concentrations were only slightly and variably affected in weanlings. Serum triglycerides and phospholipids were not altered in adult rats by the dietary cholesterol, whereas there were reductions in these lipid components in the weanlings, whether the protein was supplemented with L-lysine hydrochloride or not.4. Gluten oil was not shown to be responsible for any major portion of the differences observed between gluten and casein in their effects upon the lipids of rat serum.