CLA: The Fat That Makes You Thin
In the Woody Allen movie Sleeper, the plot involves the adventures of the owner of a health food store who is cryogenically frozen in 1973 and defrosted 200 years later. In the future, healthy food such as tofu, alfalfa sprouts, and organic vegetables are not food to be healthy, instead the ideal health foods are hamburgers, french fries, and milkshakes.
Conjugated linoleic acid is a an omega-6 polyunsaturated fatty acid that is found in the fatty acid “linoleic acid.” Interestingly, CLA acts as an antioxidant, helping to prevent free radical oxidative damage in in human tissue. CLA was first hailed for its pronounced anti-cancer effects. Linoleic acid is naturally found in dairy products and beef, and the average diet supplies 15-170 mg of conjugated linoleic acid per day. So not to far off from the movie Sleepers, CLA is found in beef patties and milk shakes. In addition to its potent anti-oxidant and anti-cancer abilities, CLA also prevents atherosclerosis (hardening of the arteries), and weight loss.
CLA works by reducing body fat by preventing fat accumulation in fat cells. CLA inhibits the activity of the enzyme lipoprotein lipase (LPL). This enzyme transfers fats from the bloodstream to the fat cells. As a result of the decreased enzyme activity the transport of fat into fat cells is blocked. At the same time CLA also stimulates the breakdown of stored body fat (lipolysis). Studies have shown that CLA increases the disintegration of cells (apoptosis), resulting in a decreased number of existing fat cells.
Early CLA experiments on laboratory rats generated considerable buzz in the industry when researchers added CLA to the diet of rats, it promoted relatively rapid weight loss in a variety of lab animals. Perhaps more important, the animals lost body fat while increasing their lean muscle mass. Earlier research reported that animals being fed CLA ate less food and lost more body fat than animals not supplemented with CLA. One research study found a diet including 0.5% CLA resulted in animals with 50% to 75% less body fat! In human studies, obese people who took CLA lost about a full inch from their waistbands over 12 weeks – compared to a control group who took no CLA and did not have a significant change in waist measurement. The groups had no change in eating or exercise habits during the period. In another study, 1,800 mg of CLA taken daily for three months was related to up to a 20% decrease in body fat.
A Norwegian study documented significant body-fat loss with just 1.8 grams of CLA per day. This double-blind, placebo-controlled, randomized study of 20 healthy, normal-weight people lasted three months. Subjects performed standardized exercises for 90 minutes, three times a week. They consumed either a placebo or 1.8 grams of a commercially available CLA mixture. Subjects taking CLA experienced significant reductions in body fat,wheres the placebo subjects showed no change in body fat.
60 overweight or obese subjects who were randomly assigned to one of five groups and received daily doses of 1.7-6.8 grams of CLA or placebo. Bodyfat was measured at baseline and then at six and 12 weeks. At the end of 12 weeks, researchers found significantly greater body-fat loss among the groups taking 3.4 grams or more of CLA compared to the control subjects. Intriguingly, the group receiving 1.7 grams of CLA experienced no significant body-fat loss, nor did the groups taking more than 3.4 grams of CLA see any additional body-fat loss. Researchers concluded that a dose of 3.4 grams results in significant body-fat loss compared to placebo, but that greater amounts of CLA do not result in greater fat loss.
Most people think that they can get adequate amounts of CLA from the diet but according to current research, 3 grams per day (or 3000 mg) is the minimum dosage of CLA in clinical testing found to provide a substantial weight loss effect. In order to get 3 grams of CLA from your diet you would have to consume 7 pounds of Grass-Fed Beef or 4 gallons of Milk to get the equivalent of 3 grams of CLA.
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