There are some supplements that can help when used in combination with a healthy diet and regular exercise. However, we view the new extract called Irvingia Gaboneniss, a West African tree, with considerable doubt. It is supposed to work on multiple fronts to promote weight loss. One is to lower blood sugar, thereby reducing fat storage. The other is to affect two hormones involved in weight control.
On the net, most refer to a 2008 trial that showed a 10 week loss of an average of 28 pounds, waist slimming and reduction in average blood sugar. However, as you will see below, there is considerable doubt about the accuracy of the study. At $40 – $50 a month, we don’t currently see this as a good investment. Take a look at the following summary from a “Low Carb Confidential” article, Nov. 28, 2008.
“Does Irvingia Really Deliver Rapid Weight Loss?”
“The short answer to this questions is: “I dunno”. I spent some time reading Life Extension Magazine. They do research that they cite, and references to follow up on (though they seem to be basing irvingia on the study below). They usually ends up pushing one of their products – in this case, irvingia. |
The stuff is from an African tree – and supposedly has almost magical powers – 4, to be exact. Here’s an excerpt from their description on what it does – it’s enough to get a fat science geek all excited:Weight Management: Reversing Leptin Resistance Fat cells produce C-reactive protein, a pro-inflammatory compound that leads to “leptinresistance.” Overweight people given Irvingia have lower levels of CRP, and therefore less CRP is able to block the activity of leptin. Leptin is important in weight management because it promotes the breakdown of fat in adipocytes and tells the brain to turn off chronic hunger messages.Hormones: Increasing Adiponectin Large fat cells secrete less adiponectin, and adiponectin is a crucial hormone that helps support insulin sensitivity as well as cardiovascular health. Overweight people given Irvingia show markedly increased adiponectin levels.Body Fat: Inhibiting the Fat Converting Enzyme An enzyme called glycerol-3-phosphate dehydrogenase facilitates the conversion of glucose into triglycerides that increase adipocyte size. Irvingia inhibits glycerol-3-phosphatedehydrogenase, thus reducing the amount of glucose (sugar) that is converted to fat in the body.Diet: Reducing Carbohydrate Absorption In order for carbohydrates to be fully absorbed, they must be broken down in the digestive tract by the amylase enzyme. Irvingia inhibits amylase, and thus reduces the amount of ingested starches that will be absorbed as sugar.It probably helps you get better gas mileage in your car as well. The kicker is Life Extension’s claim: “Several studies demonstrate the weight loss properties of Irvingia. In the largest placebo controlled human study, those taking Irvingia lost 28 pounds over a 10-week period compared to only up to 3 pounds in the placebo group. The study participants did not alter their diet.” So the question of the moment for me is: should I try it? It seems like cheating if the stuff works – and further proof of my being an idiot and sucker as well if it doesn’t. Now I lost 90 lbs (avoiding processed foods, exercise, reducing dairy products and eating large food portions). I think that any of the above is acceptable if it helps you to lose weight. If you can find a way to get the pounds off short of starvation, or something else really damaging, you can sweat the details later. A study on Irvingia I found a study on irvingia, (Here). I’ve excerpted parts below. If you are really interested, you can read the source. Here is the gist of their study: A total of 40 obese subjects aged between 19 and 55 years were selected. None of these subjects took any weight reducing medication and none was following any specific diet. Subjects were given two different types of capsules containing 350 mg of Irvingia gabonensisseed extract. Three capsules were taken three times daily (a total daily amount of 3.15 g – much more than Life Extension recommends @ 150 mg. twice per day). So the results can’t really be compared when the dose is so different. These people were also counseled to adhere to a low fat diet, which helps to obscure the actual change from irvingia alone as it introduces a second variable. Does any measured change have to do with the irvingia, the low-fat diet, or a combo of both? Here’s what it says about irvingia’s impact on body composition: 1. Irvingia gabonensis induced a decrease in weight of 2.91 ± 1.48% (p < 0.0001) after two weeks and 5.6 ± 2.7% (p < 0,0001) after one month. 2. Although the percentage of body fat was not significantly reduced with both placebo and IG, the waist circumference (5.07 ± 3.18%; p < 0.0001) and hip circumference (3.42 ± 2.12%; p < 0,0001) were significantly reduced by IG. 3. A reduction of 1.32 ± 0.41% (p < 0.02) and 2.23 ± 1.05% (p < 0.05) was observed with the placebo after two and four weeks respectively of treatment. What I translate this to mean: Someone weighing 200 lbs. could expect to lose 10 lbs. in a month. As body fat isn’t significantly different in the control group and the irvingia group, the weight loss must come from water, muscle, or the study didn’t control this variable properly. If you started out with a 40 inch waist, you were a 38 inch waist after a month. OK – that’s not bad – but as this study only lasted a month, we can’t see the acceleration of weight loss between month 1 and month 2 described in the Life Extension article. Some impressive results were also seen in blood pressure and serum cholesterol:
These reductions aren’t bad, but bringing down each number by 5 doesn’t seem to be all that amazing – and again – might it have had something to do with the low fat diet? Who knows? And what’s with the seemingly large margins of error here? And why would they vary so much between the active and placebo group? For example: the margin of error for the first reading of the folks taking irvingia has a margin of error of +/- 19.57. For the placebo group, it’s +/- 5.05. Why would this differ by almost a factor of 4? Next up is the reported effect on blood total cholesterol (TC), triglyceride (TRI), high density lipoproteincholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c) and glucose. Looking at the reductions, it seems impressive. However, do you notice that the active group starts out with total cholesterol at 215 and the placebo group at 163? The active group is defined as having high cholesterol by that number, and the control group has cholesterol that would be characterized by some as dangerously low. I might be missing something, but shouldn’t the control group be more or less the same as the active group in a well-designed study? And where do you find 20 obese people with an average total cholesterol of 163? Not around here. Also – the reported margin of error again still seems high. What I’m seeing is what I would say is an interesting study that leads one to believe something is going on here, but it is too poorly designed to tell us what. Our researchers also did have some speculation on what’s happening here. This is where research is replaced by guesswork. That’s not necessarily bad – an educated guess is better than saying: I dunno. The soluble fibre of the seed of Irvingia gabonensis like other forms of water-soluble dietary fibres, are “bulk-forming” laxatives. Irvingia gabonensis seeds delay stomach emptying, leading to a more gradual absorption of dietary sugar. This effect can reduce the elevation of blood sugar levels that is typical after a meal. Controlled studies have found that after-meal blood sugar levels are lower in people with diabetes. Overall diabetic control is improved with soluble fibre-enriched diets according to preliminary and controlled trials. Like other soluble fibers, Irvingia gabonensis seed fibre can bind to bile acids in the gut and carry them out of the body in the faeces, which requires the body to convert more cholesterol into bile acids. This can result in the lowering of blood cholesterol as well as other blood lipids. Studies have shown that supplementation with several grams per day of soluble fibre significantly reduced total blood cholesterol, LDL cholesterol, and triglycerides and in some cases raised HDL cholesterol, these being comparable with effects noticed with Irvingiagabonensis. I’ve edited this somewhat for clarity, though I don’t think I’ve altered their point: irvingia is a bulk-forming laxative (like psyllium) and this type of fiber is already known to improve cholesterol bers. |