Objective: To study the effects of a High-carbohydrate, Low-fat (HC/LF) diet on the levels of phospholipids and triglycerides in serum and analyze their association with anthropometric indexs and serum biochemical traits.
Methods: 56 healthy volunteers had a HC/LF diet for 6 days. The body weight, waist circumference, hip circumference, biceps circumference, and skinfold thickness were measured before and after the HC/LF diet. Venous blood was taken after fasting of 12 hours. The levers of high density lipoprotein-phospholipid (HDL-PL), high density lipoprotein-triglyceride (HDL-TG), high density lipoprotein-cholesterol (HDL-C) were enzymatically determined after precipitation of serum apoB containing lipoproteins with phosphotungistic acid and non-LDL-phospholipid (NLDL-PL), non-LDL-triglyceride (NLDL-TG), non-LDL-Cholesterol (NLDL-C) levels were enzymatically determined after precipitation of serum LDL with polyethylene sulfate. The levels of serum LDL-PL, LDL-TG, and LDL-C were calculated by minus of non-LDL from serum PL, TG, and TC levels, respectively. The level of TRL-TG was calculated by minus of HDL-TG, LDL-TG from total TG. The level of serum insulin was measured by electrochemical luminescence.
Results: The levels of fasting serum PL, HDL-PL and LDL-PL decreased significantly after HC/LF diet, whereas the levels of TG, HDL-TG and insulin increased. Correlation analyses indicated that after HC/LF diet the change of serum PL (APL) had a negative correlation with the change of BMI(deltaBMI),a positive correlation with the change of HDL-TG(deltaHDL-TG) and insulin (delta insulin). The change of serum LDL-PL (deltaLDL-PL) had a negative correlation with deltaBMI and waist circumference (deltaAWC), meanwhile the change of HDL-PL (deltaHDL-PL) had a negative correlation with deltaHDL-TG, a positive correlation with the change of HDL-C (deltaHDL-L). A positive correlation existed between deltaHDL-TG and wais/hip circumference ratio (deltaW/H).
Conclusion: HC/LF diet can decrease serum PL, HDL-PL level but increase serum levels of TG and insulin. The change of serum PL level had a negative correlation with deltaBMI,a positive correlation with deltaHDL-TG and delta insulin.