Conjugated linoleic acid accelerates weight loss and improves anthropometric measures in overweight young adult males during weight loss program

Background: With the increasing prevalence of obesity in Iraq, an increasing trend towards better physical fitness has emerged among young adults. At the same time, an increasing number of dietary supplements is offered to improve fitness and shed the extra weight. Conjugated linoleic acid (CLA) is commonly used for such purpose.

Aim: The current study was designed to test if CLA can actually accelerate weight loss when combined with dieting and moderate exercise and to examine its effect on anthropometric measures of obesity.

Subjects & methods: Sixty young males enrolled willingly in the study and were put on a low-carbohydrate low-fat diet and moderate high intensity interval exercise (HIIT) program. Forty of them were given CLA (1000 mg/day) for 8 weeks while the remaining twenty served as control group. Body mass index (BMI), waist/hip ratio (WHR), sagittal abdominal diameter (SAD) and body adiposity index (BAI) were recorded as baseline and again after 4 and 8 weeks.

Results: The CLA-treated group showed significantly greater reduction in all four measures by the end of the study. The control group had significant but less decrease in BMI & SAD but not in WHR or BAI. The percent change difference between the first and second four weeks of the study also showed statistical difference among the two groups and for different measures. The most significant finding was that SAD dropped more rapidly during the first 4 weeks of the study indicating a preferential loss of visceral fat. Oppositely, WHR dropped during the second half of the study indicating loss of more abdominal fat stores.

Discussion: Regardless of the mode of action of CLA, its accelerative effect in weight loss is augmented by the combination with dieting and physical activity. It also corresponds to the natural body preference to losing the more metabolically active visceral fat prior to switching to the loss of subcutaneous fat. Whether or not this effect is sustainable requires further study.

overweight, obesity, conjugated linoleic acid, body mass index, waist/hip ratio, sagittal abdominal diameter, body adiposity index, visceral fat, subcutaneous fat

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