Lipids, lipoproteins and fatty acid composition in obese adolescents undergoing a very low calorie diet.

Sixteen obese adolescents (mean +/- SD age: group I 12.5 +/- 2.1 and group II 12.0 +/- 2.5 years) were treated at least 3 weeks with two different very low calorie diet (VLCD) regimens. The VLCD in group I contained 33g proteins, 25.5g carbohydrates and 0.7g fat (240 kcal, 1004KJ) and in group II 44g protein, 33g carbohydrates and 0.9g fat (320 kcal, 1339KJ). After the 3 weeks treatment total serum cholesterol decreased from 180 +/- 34 mg/dl in group I and 184 +/- 34 mg/dl in group II respectively, to 125 + 16 mg/dl and 120 + 22 mg/dl. This fall was mainly due to the highly significant decrease of LDL-cholesterol. VLDL-cholesterol, HDL-cholesterol and triglycerides in group I remained almost unchanged. In group II triglycerides increased significantly from 81 +/- 19 mg/dl to 104 +/- 19 mg/dl and HDL-cholesterol decreased slightly. The LDL-C HDL-C- ratio in both groups improved considerably. Fatty acid composition of the serum lipids changed only slightly: In total serum linoleic acid levels declined slightly in group I and remained constant in group II. Linoleic acid content in cholesterylesters declined moderately in group I from 37.5 +/- 5.6% to 34.8 +/- 5.6% whereas arachidonic acid increased slightly in both groups. In phospholipids, oleic acid declined in both groups significantly, linoleic acid declined significantly in group I and arachidonic acid increased in group I significantly. Similar changes occurred in triglycerides. After 3 weeks treatment with a practically fat free alimentation no biochemical signs of essential fatty acid deficiency could be detected.