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. 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 “leptin resistance.” 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.
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:
Weeks: 0 2 4
SBP (mmHg) Active 136.41 ± 19.57 132.66 ± 18.48* 132.83 ± 17.97*
Placebo 134 ± 5.05 121.5 ± 5.89 123.83 ± 2.92
DBP (mmHg) Active 98.5 ± 19.52 97.5 ± 22.80 94.08 ± 11.07
Placebo 93.50 ± 10.31 93.83 ± 7.41 91.5 ± 6.53
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 lipoprotein cholesterol (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’m just a dope, 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 don’t know.
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 numbers.
As they don’t mention weight loss at all, I imagine that they have no clue as to why anyone lost weight, but were too embarrassed to admit it. The only conclusion that I come to after reading this is that any fiber therapy, like Metamucil, can help reduce blood lipids, and Metamucil is way cheaper than irvingia. I’m still considering it – one poorly designed study (in my estimation) does not prove nor disprove anything.
This Inquiry Has Gotten Complicated!
I’m not an investigative reporter – just someone curious about irvingia as a way to facilitate weight loss. This has brought me into a world of ‘weight loss supplements’ – I don’t think I ever tried a weight loss supplement in my life, to be honest.
When Life Extension mentioned irvingia, and they breathlessly endorsed it as “more weight loss than any other discovery in supplement history”‘, I took notice. 28 lbs. in 10 weeks is phenomenal, but ingesting something I never heard of, as well as a cost over $100 for a 10-week supply, led me to do some digging.
As I mentioned, irvingia searches on the Internet didn’t turn up much. Irvingia is a tree nut from Africa used in food. It has a lot of fiber and can act as a ‘bulk-forming’ laxative when eaten. There have also been some studies, so far they all seem to have been done in Cameroon, that indicate that it might also have favorable blood-sugar and cholesterol profile effects.
I also found that bodybuilders have been the most vocal about this stuff on their boards. Seems to me that bodybuilders are about the smartest folks you can find when it comes to bodyhacking. They are always looking for ways to get more pumped, and healthier, and will play with all sorts of supplements to do so.
They have also been scammed a lot by peddlers of supplements that claim to provide bodybuilder nirvana but fail to deliver. Their studies should be looked at as highly suspect.
Both of these studies on irvingia gabonensis were conducted by Julius Oben, which raises huge red flags to me. Oben is the researcher behind a study earlier this year showing that cissus quadrangularis was effective as a fat loss aid. After digging around, I found that Oben, the lead researcher, is actually employed at Gateway Health Alliances Inc, which supplied all the testing materials (and probably funded) all of these studies. (If you search, you’ll find “All testing materials were supplied by Gateway Health Alliances”). Apparently, they’ve hired Oben as the “Chief Scientific Officer” at Gateway. How’s that for impartial.
In addition, Oben holds a patent on Cissus’ use as a weight loss aid. Oben is the “inventor” and Gateway Health Alliances is the assignee. Apparently Oben and Gateway Health Alliances have been working together since as early as 2000.
In 2006, Oben published a similar study where he used a different product from Gateway Health Alliances called Cylaris. It was a mixture of several ingredients including cissus. Of course, it had amazing results, results that Gateway Health Alliances relies on heavily in their marketing. This doesn’t mean that Oben’s research is necessarily bogus. But can you tell me why an American corporation is having an obscure university in a poor West African country do all the research on their products, while simultaneously employing the lead researcher?
Smells like bad fish to me.
When you read through all this, it does seem that Dr Oben does have a relationship with the Cylaris, and the Cylaris product does make similar weight loss claims.
As to the author’s questioning of the journalistic credentials of ”Lipids in Health and Disease”, I do find this journal listed on the Georgetown Library website, so at least the librarians there think it’s legit.
What might be going on here is that we have a researcher that specializes in looking for weight-loss formulations. He came up with one around 2000, and sold it to a company that licensed it to Iovate, where it met with some success. Dr Oben has moved on to the study of irvingia. Though perhaps flawed, his studies reveal that something is going on here. Maybe this one is the real deal. He goes to the Life Extension folks, instead of Iovate, and shows them the research. They do their own research on the product and they think that the stuff is the real deal, and launch a product.
The Life Extension people have a lot more to lose. They sell a lot of supplements, memberships, and even prescription drugs. In my years reading their magazine, I honestly believe that they believe in what they are doing. If they were to back this product and put their name on it, and it is garbage, or a dud, there could be blowback. This could harm their reputation and credibility.
My conclusion at this juncture is we can’t be certain of the effects of irvingia. Studies contradict each other daily. Why? Because clinical research is hard. It’s also expensive and time consuming. In addition, researchers are human and suffer from the same cognitive biases that everyone else does. That’s why there’s the concept of peer review. But peer review can’t save us when the peer holds the same biases.
We need to research the decisions we make about our health to the best of our ability, based on the best information we have, knowing that it is lacking, and make informed decisions on them. This post is just as suspect as all the other information presented here. I suffer from the same biases and blind spots that the researchers do.
At this juncture, I see a product that might work. I still have questions, and will probably continue my research.