Friday, January 24, 2014

Do fat-burning supplements really work? by Jerry Brainum

When I first began bodybuilding, the choices for "fat burners" was strictly limited. In those days, you relied on what was called "lipotropics," which means "fat loving."The primary lipotropics were two nutrients, namely choline and inositol. The notion that they help rid the body of excess fat was based on the fact that when you are deficient in choline, your liver reacts by increasing the storage of fat in the liver. This is the first step of liver failure. Choline helped to rid the fat of liver by offering what chemists call methyl donors, which allow the liver to effectively process excess fat through transporting them out of the liver through the production of lipoproteins. Choline aided in the production of these lipoproteins. Somehow, the choline-associated process of liver fat reduction transmogrified into an overall body fat loss effect. In fact, however, neither choline or inositol were ever shown to promote systemic fat loss.
   The other popular "fat loss" supplement years ago were kelp tablets. Kelp is a rich natural source of iodine. Iodine, in turn, is essential for the production of thyroid hormone, which primarily controls the resting metabolic rate. So the idea was that if you took enough kelp tablets, you would boost thyroid hormone output, which would lead to increased resting metabolism, and then--presto!--you lost body fat. Unfortunately,none of us who gobbled handfuls of kelp tablets knew at the time that excess iodine intake had a paradoxical reverse effect of inhibiting thyroid hormone synthesis.
   In recent years, the category of "fat burning" supplements has become a big business, garnering a large percentage of the profits of the billion dollar food supplement business. One reason for this is that unlike other supplements targeted to bodybuilders and athletes, fat burners are a crossover supplement, appealing to anyone with a desire to lose excess body fat. Since so many people are obese, the market for such supplements is immense. Adding to this is the fact that there are no current effective pharmaceutical weight-loss products available.  Most of the weight-loss drugs work by either suppressing appetite, or blunting enzymes that digest dietary fat. Not only are such drugs ineffective for most people, but they also produce frequent unpleasant side effects.
   Thus, if you could offer a safe, over-the-counter fat-loss supplement, it would be very appealing. Probably the most effective supplement in the category was the combination of ephedrine and caffeine. Some formulas also added a form of aspirin, natural or otherwise, because it extended the effectiveness of the ephedrine/caffeine duo. Such products did work because they provided an enhanced thermogenic effect, which simply means that they converted calories into heat, which also involved a rise in the resting metabolic rate. In addition, ephedrine and caffeine also promoted the conversion of inactive thyroid hormone into the active form, which as noted, would favorably affect fat loss by maintaining an elevated resting metabolism. But in 2004, ephedrine and caffeine were removed from the commercial market due to concerns about toxicity, especially in relation to causing heart attacks and strokes. In fact, ephedrine and caffeine had a long history of safety, and when used in suggested doses, were safe, with the notable exception of those with pre-existing cardiovascular disease. Warnings on all product labels advised that those with CVD should not use the product, but many ignored the warning to their peril. In other cases, people overdosed, thinking that if two pills worked, ingesting eight or ten would speed fat loss. Small wonder why such idiots experienced health problems.
    So ephedrine was banned, but caffeine went on to become the number one active ingredient in current fat loss supplements. There is no doubt that caffeine does modestly boost resting metabolic rate. It also boosts the release of catecholamines, hormones such as epinephrine and norepinephrine, which do promote fat mobilization. But a frequently overlooked fact is that caffeine itself does not burn or oxidize fat. It merely promotes the exit of stored fat into the blood. If you do nothing to burn the fat, such as exercise, the fat is simply sent right back to be restored in the fat cells. This is a key point regarding fat loss supplements. While they may aid the process of fat loss through a heightened release of fat, they do not themselves actually burn fat. Most ads for such products are deceptive, in that they lead unwary consumers to believe that the product itself burns fat. It doesn't.
    The other frequent ingredient often seen in current fat-loss supplements is green tea. Green tea contains a number of potent antioxidants, with the primary one being EGCG, that do seem to provide a mild thermogenic effect. One suggested way that green tea helps burn fat is through blunting an enzyme that degrades catecholamines called COMT. If you extended the time of catecholamine activity, you would theoretically burn more fat if you also exercised. However, this effect of green tea remains a theory, rather than a proven commodity. More recent studies of green tea provided alone show little or no fat-reduction effect. On the other hand, green tea may be synergistic with other substances, including caffeine, and some studies have indeed shown this. The main problem with green tea is that some people have experienced severe liver problems after using it. Some suggest that it was the green tea content of a popular fat loss supplement called Hydroxycut that resulted in users showing severe side effects, many of whom experienced liver problems. This has never been verified, however. Indeed, some formulations of green tea were found to be tainted with the herb, germander, which has been shown to be toxic to the liver. In fact, germander was banned in France in 1992 after 26 cases of hepatitis were reported in users of the herb.
     After ephedrine was banned, companies hustled to find an appropriate substitute. One candidate was the similarly structured compound, synephrine. Synephrine, like ephedrine, acts as a sympathomemetic, meaning that it works like catecholamines to promote fat release from fat cells. The initial advertising suggested that synephrine worked by promoting the activity of beta-3 adrenergic receptors. The only problem with this was that this particular fat-cell receptor is most active in brown adipose tissue, which, while existing in humans, is far more active in rodents. Indeed, attempts by drug companies to produce a beta-3 activating drug for human use has uniformly failed to promote significant fat loss, but has produced significant side effects.
    Some of the most recent fat-loss supplements list esoteric herbs that few people have ever heard of. If you check the medical literature for information about the efficacy of such herbs, you'll find that there is a dearth of human research, and in many cases, there is none. The inclusion of such substances in fat loss supplements is based entirely on a few animal studies, in which the animal subjects are often supplied inordinately large doses to promote fat loss. How humans would react to ingesting similar doses is anyone's guess.
   Another, more alarming, problem related to fat loss supplements is possible contamination with ingredients not listed on the label. This came to light recently, when it was revealed that certain OTC fat loss supplements contained a prescription drug linked to heart problems. The lack of quality control in the supplement industry makes this a genuine risk. In other cases, the production of supplements is farmed out to Chinese companies, where quality control is non-existent. This is far more common than is realized. I recently found out that a popular online supplement company's house brand of supplements is manufactured entirely in China. When I wrote to the company for confirmation about this, they refused to answer me.
   One way to prove the efficacy of any food supplement is through quality research. But such research is expensive, and since the ingredients in most supplements are not patent-protected, many companies do not sponsor such research. Those that do often produce studies that aren't very convincing, involving too few subjects, no placebo, no controls, and no comparison to similar products. As such, such "studies" are merely ads for the company product.
   So will fat burners fulfill their promise? The best way to view them is as minor adjunctive diet aids. They do boost resting metabolism for about 6 hours following ingestion, and when combined with a suitable diet and exercise program, will help promote some additional fat loss. Will they produce such body composition change without exercise or diet? Absolutely not. There is only one substance that I am aware of that will promote extensive fat loss without exercise or diet. That substance is called dinitrophenol or DNP. It works by inhibiting energy production in the cell. The good news is that it often produces a fat loss of a half-pound of fat a day. The bad news is that it's highly toxic, and has caused several recent deaths.Those seeking an easy road to effortless fat loss will find a road that never ends.


©,2015 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited

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The Applied Ergogenics blog is a collection of articles written and published by Jerry Brainum over the past 20 years. These articles have appeared in Muscle and Fitness, Ironman, and other magazines. Many of the posts on the blog are original articles, having appeared here for the first time. For Jerry’s most recent articles, which are far more in depth than anything that appears on this blog site, please subscribe to his Applied Metabolics Newsletter, at This newsletter, which is more correctly referred to as a monthly e-book, since its average length is 35 to 40 pages, contains the latest findings about nutrition, exercise science, fat-loss, anti-aging, ergogenic aids, food supplements, and other topics. For 33 cents a day you get the benefit of Jerry’s 53 years of writing and intense study of all matters pertaining to fitness,health, bodybuilding, and disease prevention.


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