Effects of Dietary α-Linolenic Acid-rich Diacylglycerol on Body Fat in Man (1): Lowering Effect on Body Fat

Abstract

This study was conducted to investigate the effects of dietary diacylglycerol rich in α-linolenic acid (ALA-DAG) on body fat in human. The ALA-DAG contained 49% α-linolenic acid and was prepared from linseed oil using immobilized lipase. This study consisted of two types of dietary restriction and two types of diet. In test 1, 2.5-3.7g ALA-DAG was ingested as an edible oil under restriction of the amount of oil intake (50±5 g/d) for 12w (66 subjects). In tests 2 and 3, 2.5g ALA-DAG was ingested as a drink for 16w under calorie intake restriction determined based on subject’s calorie requirements (48 and 30 subjects, respectively). In all tests, after a 4 week control-diet period, the subjects started the diet and every 4 weeks during the test period, blood tests for fat metabolism were carried out and body indices (weight, waist, skinfold thickness, body fat computed with tomography) were measured. In subjects ingesting diets containing 2.5 g of ALA-DAG (test 1, 2 and 3), a significant decrease (-6.3∼-13.4%) of body fat area was observed. It was suggested that ALA-DAG had two characters of diacylglycerol and n-3 polyunsaturated fatty acid because of the high effectiveness of a small dose. These results showed that ALA-DAG improved fat metabolism and reduced body fat, and we speculate that ALA-DAG may be useful to reduce the risk of diseases associated with obesity.