Effects of dietary saturated,monounsaturated and polyunsaturated fats on plasma lipids and lipoproteins in diabetic rats*

The effects of altering the type of dietary fat on plasma lipid and lipoprotein levels were investigated in streptozotocin‐diabetic rats fed non‐purified diets containing corn oil, olive oil, cod‐liver oil, sheep tallow and lard. After 32 days of experimental feeding, plasma levels of glucose, triglycerides, total cholesterol, low density and high density lipoprotein cholesterol were determined. Body weights and food intake were also measured. In neither animal group did the type of fat in the diet affect significantly the plasma levels of lipids and lipoproteins and their calculated ratios, and plasma glucose, body weight change or accumulative food intakes. In all studied diabetic rats, significant correlations were observed between body weight change and the following plasma variables: total cholesterol level (r = —0.37, P < 0.03), low density lipoprotein cholesterol level (r = —0.38, P<0.03) and triglycéride concentration (r = —0.36, P < 0.04). A significant positive correlation (r = 0.60, P < 0.0003) was also found between plasma levels of glucose and triglycérides. No significant correlations were noticed between accumulative food intakes and any of the studied variables. It is concluded that, in uncontrolled hyperglycemia in diabetes, the type of fat in the diet exerts little or no influence on plasma lipid and lipoprotein concentrations.