Recent Studies on CLA

CLA may help support weight loss in healthy overweight individuals

Journal of Nutrition, 'Conjugated Linoleic Acid Reduces Body Fat Mass in Overweight and Obese Humans' Henrietta Blankson et al, 2000.

Conjugated linoleic acid (CLA) has been shown to reduce body fat mass (BFM) in animals. To investigate the dose-response relationships of conjugated linoleic acid with regard to BFM in humans, a randomized, double-blind study including 60 overweight or obese volunteers (body mass index 25?35 kg/m2) was performed. The subjects were divided into five groups receiving placebo (9 g olive oil), 1.7, 3.4, 5.1 or 6.8 g conjugated linoleic acid per day for 12 wk, respectively.

Repeated-measures analysis showed that a significantly higher reduction in BFM was found in the conjugated linoleic acid groups compared with the placebo group. The reduction of body fat within the groups was significant for the 3.4 and 6.8 g CLA groups.

No significant differences among the groups were observed in lean body mass, body mass index, blood safety variables or blood lipids. The data suggest that conjugated linoleic acid may reduce Body Fat Mass (BFM) in humans and that no additional effect on BFM is achieved with doses.

American Journal of Clinical Nutrition, 'Conjugated linoleic acid supplementation for 1 y reduces body fat mass in healthy overweight humans', Jean-Michel Gaullieret al, June 2004

Background: Short-term trials showed that conjugated linoleic acid (CLA) may reduce body fat mass (BFM) and increase lean body mass (LBM), but the long-term effect of CLA was not examined.

Objective: The objective of the study was to ascertain the 1-y effect of CLA on body composition and safety in healthy overweight adults consuming an ad libitum diet.

Design: Male and female volunteers (n = 180) with body mass indexes (in kg/m2) of 25?30 were included in a double-blind, placebo-controlled study. Subjects were randomly assigned to 3 groups: CLA-free fatty acid (FFA), CLA-triacylglycerol, or placebo (olive oil).

Results: BFM in the CLA-triacylglycerol and CLA-FFA groups was respectively lower than that in the placebo group. Subjects receiving CLA-FFA had greater LBM than did subjects receiving placebo. These changes were not associated with diet or exercise. LDL increased in the CLA-FFA group, HDL decreased in the CLA-triacylglycerol group, and lipoprotein(a) increased in both CLA groups compared with month 0.

Conclusion: Long-term supplementation with CLA-FFA or CLA-triacylglycerol reduces BFM in healthy overweight adults.

CLA may help to improve cholesterol levels

Journal of Nutritional Biochemistry, 'Effect of supplementation with conjugated linoleic acid on human serum lipids and body fat', V. Mousgios et al, 2001

Background: Conjugated linoleic acid (CLA) is a natural component of meat and dairy products with anticarcinogenic, fat lowering, antiatherogenic and anticatabolic activity in animals. The purpose of this study was to examine the effect of CLA supplementation to humans on body fat, certain biochemical parameters of serum, and the CLA content of serum lipids.

Method: Twenty-two volunteers were divided into a study group and a control group in a doubly blind design. The study group received 0.7 g of CLA for four weeks and 1.4 g of CLA for the next four weeks, while the control group received placebo. Diet was controlled and no significant differences in energy or macronutrient intake were found between the two groups. Measurements were taken at baseline, four weeks, and eight weeks.

Results: The sum of the thickness of ten skinfolds, percentage body fat calculated from it and fat mass was significantly reduced in the CLA group during the second period but not overall during the study. Serum HDL-cholesterol decreased significantly andtriacylglycerols as well as total cholesterol tended to decrease in the CLA group during the first period. The CLA content of serum non-esterified fatty acids, triacylglycerols, phospholipids, and cholesteryl esters increased gradually with supplementation; the CLA content of total serum lipids doubled at the end of the study compared to baseline. Phospholipids had the highest CLA content regardless of supplementation.

Conclusion: These data indicate that supplementation with 0.7-1.4 g CLA daily for 4-8 weeks may modulate body fat and serum lipids, as well as increase the CLA content of serum lipids in humans. Thus it may help lower cholesterol levels.