Scientists proclaim supplementation with conjugated linoleic acid effective in combating the effects of holiday weight gain.

It is estimated that more than half of adult Americans (up to 65%) are either overweight or obese.  Because being overweight significantly increases the risk of death due to heart disease, stroke and certain types of cancer, researchers at the University of Wisconsin, Madison set out to determine what could be done about it.

Specifically, they investigated whether or not supplementation with conjugated linoleic acid (CLA), which had shown to drastically reduce body fat in lab animals, would work for humans.

They discovered a very specific and important benefit of CLA – its effect on holiday weight gain.  “Our results indicate that CLA plays a role in mitigating weight gain associated with the holiday season.  CLA significantly reduced body weight compared to placebo during the 6-month study, and during the holiday season, in particular.  In November and December, the placebo group had a significantly higher rate of weight gain compared to the CLA group,” they wrote.

Abstract
The role of conjugated linoleic acid in reducing body fat and preventing holiday weight gain

By A.C. Watras, A.C. Buchholz, R.N. Close, Z. Zhang and D.A. Schoeller

Objective:  The incidence of obesity and overweight in the US has increased considerably during the past two decades and currently affects 65% of the adult population. Research has indicated that small, yet irreversible, gains during the holiday season contribute to increases in weight during adulthood. Conjugated linoleic acid (CLA), a naturally occurring dietary fatty acid, has been found to reduce weight gain and dramatically decrease fat mass in animals. Although research in humans has shown inconsistent results, most studies have been of insufficient duration or have utilized body composition methods that are less accurate than the currently accepted criterion.

Design: Randomized, double-blind, placebo-controlled study of 3.2 g/day CLA for 6 months.
 
Subjects:  Forty healthy, overweight subjects (age: 18–44 years; body mass index: 25–30 kg/m2)
 
Measurements:  Body composition by the four-compartment model, resting metabolic rate (RMR) by indirect calorimetry, self-reported physical activity and dietary intake, and blood chemistries were determined at baseline and after 6 months. Body weight was measured monthly during the pre-holiday season (August–October), holiday season (November–December) and post-holiday season (January–March). Adverse events were assessed monthly.
 
Results:  Compared to CLA, the placebo group showed a greater rate of weight gain during the holiday season (P=0.01). Within the placebo group, holiday weight change was significantly greater compared to the pre-holiday period (August–October) (P=0.03). Six-month change in body composition was improved with CLA compared to placebo (P=0.02), and body fat was significantly reduced within the CLA group (-1.02.2 kg, P=0.05). CLA had no effect on RMR, physical activity or dietary intake. The rate of reported negative emotions decreased significantly with CLA, although there was no difference in any other category of adverse event. In comparison to the placebo, CLA did not affect insulin resistance, blood lipids and markers of liver function or markers of inflammation, with the exception of a significant decrease in a biomarker of endothelial dysfunction.
 
Conclusion:  CLA supplementation among overweight adults significantly reduced body fat over 6 months and prevented weight gain during the holiday season. Although no adverse effects were seen, additional studies should evaluate the effect of prolonged use of CLA.