UPDATE: Here is my last post on Irvingia from 12/30/11 – 3+ years after the experiment.
I found a study on irvingia - The effect of Irvingia gabonensis seeds on body weight and blood lipids of obese subjects in Cameroon - published in 2005. You can read it yourself here. I’ve excerpted parts below – if you are really interested, go read the source, as my interpretation could be off.
Here’s the gist of their study:
A total of 40 obese subjects aged between 19 and 55 years were selected from a group responding to a radio advertisement. After physical examination and laboratory screening tests, diabetics, pregnant and lactating women were excluded. 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 (active formulation)… Three capsules were taken three times daily, one-half hour before meals (a total daily amount of 3.15 g of Irvingia gabonensis seed extract) with a glass of warm water… The subjects were also interviewed about their physical activity and food intake during the trial, and were instructed to eat a low fat diet (1800 Kcal) as well as keep a record for seven consecutive days (using household measurements).
OK – these folks were taking way more irvingia than Life Extension recommends - Life Extension recommends 150 mg twice per day, while the people in this study were taking 3 grams of the stuff – more than 10 times the amount.
So what Life Extension is reporting is somewhat ‘apples-to-oranges’ as this study and it’s 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?
This question can’t be answered from this study, in my estimation.
Let’s continue. Here’s what it says about irvingia’s impact on body composition:
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. 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. 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 betwen month 1 and month 2 described in the Life Extension article.
Some impressive results were seen in blood pressure and serum cholesterol:
Effect of Irvingia gabonensis on systolic (SBP) and diastolic (DBP) blood pressure
| Treatment period (weeks) | ||||
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|
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| 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 lipoproteincholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c) and glucose.
| T-cholesterol | TRI | HDL-c | LDL-c | LDL/HDL | T-cho/HDL | GLUCOSE | ||
| Active | Initial | 215 ± 55.12 | 162 ± 33.15 | 61.23 ± 20.36 | 121.37 ± 36.3 | 1.98 ± 1.78 | 3.51 ± 2.70 | 3.8 ± 1.92 |
| Final | 130.68 ± 39.5 | 89.22 ± 55.63 | 89.9 ± 28.44 | 66.08 ± 34.27 | 0.735 ± 1.20 | 1.45 ± 1.38 | 2.57 ± 1.03 | |
| Placebo | Initial | 163.70 ± 25.32 | 130.65 ± 37.82 | 31.38 ± 25.21 | 105.06 ± 11.86 | 5.05 ± 3.94 | 6.44 ± 3.37 | 3.6 ± 0.41 |
| Final | 158.36 ± 30.46 | 100.52 ± 32.55 | 41.20 ± 19.53 | 98.55 ± 27.99 | 3.19 ± 1.85 | 4.51 ± 2.07 | 3.9 ± 0.74 |
Again, looking at the reductions, it seems impressive, but 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.
Now – I have no right interpreting these results – I’m no researcher. If any one of the really smart people that read this blog see a mistake in my understanding, please post.
But 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 do 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, but it is what it is – a guess:
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 and 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 - Metamucil) 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 post continues…Part 3.
Filed under: Articles, general health, Supplements Tagged: | irvingia
I joined LEF on the advice of my 88 year old father in law who swears by it and takes a ton of their supplements. I’d bet that if you studied his physiology, he’s in his 70′s compared to the rest of us.
The only supplement I’ve ever tried is their Esophoguard orange-peel extract for GERD, it works as advertised and saves me from spending my life on PPIs as my doctor suggested. I take it about once or twice a year whenever symptoms flare up.
I can’t vouch for the rest of their stuff, but I’m following your blog pretty carefully.
What we’re seeing here is, at least in part, caloric excretion which is a safe, natural way to lose or control weight. I’d give it a try if I were over weight but would probably use natural sources of fiber by consuming more non starchy vegetables.
I’ve tried to drum up some interest in the unabsorbed calories (calorie excretion) phenomenon with little apparent success. You can access what I’ve written by Googling “David Brown Unabsorbed Calories” or “David Brown calorie excretion.”
OMG those people were just wasting away!!!!!!! The fat percentage didn’t change which suggests to me that the calories got restricted, carbs went up, and as a result so did the insulin, which resulted in the fat getting locked in the adipose tissue and the body eating away at the organs and muscle.
So this proves very nicely that you can’t lose FAT on a low fat diet. Doesnt it?
Oh I jumped the gun. I see they didn’t lose significantly more fat % compared to the control group. But still.
Hi Dan,
You might be right, but as the study seems poorly designed, it allows us to draw any number of conclusions.
More to come on this topic…
LCC
I have learned that it pays to be thorough. Regarding research I previously assumed to be about caloric excretion, turns out it was misinterpreted (or misrepresented) by the authors of the two books I read.
At any rate, here’s some discussion on the Calories per hour forum that LCC readers might find interesting:
http://www.caloriesperhour.com/forums/forum19/75.html
“…shouldn’t the control group be more or less the same as the active group in a well-designed study?”
An excellent question. Questions like that sometimes lead to the discovery of fraud, as in this article:
http://www.bmj.com/cgi/content/full/331/7511/288
You know Lou, I’d be surprised if it was an outright fraud – unjustified optimism? Maybe. A poorly designed study? It happens all the time.
LEF is not a ‘fly-by-night’ – they’re not some company named something like ‘Vitanutronics’ that appears out of nowhere and comes up with some magical weight-loss potion, intending to make a quick buck and fold before the authorities catch up with them. LEF has been around for a while, and has a significant reputation to tarnish.
I have their ‘Disease Prevention and Treatment Book’ – you get this free with membership – it’s huge – over 1600 pages, and written in a style that does not offend a long-term skeptic like me. It’s a worthwhile read.
It doesn’t make them infallible, but it does make it seem that they have more to lose than most supplement companies. Look at the posts here – they have a number of supporters that will be *very* disappointed in them if this is bunk.
Me? I still think the jury is out on this – it takes a month to see significant results. I think the next few weeks might tell a fuller story.
I *do* appreciate your skepticism – keep the comments coming – keeps it real.
Oh – by the way – that name Vitanutronics – I just made that up – it’s a cool name, don’t you think?
I checked Google – 0 hits – it’s an original.
Anyone want to start a fly-by-night supplement company? Contact me for licensing info.
I agree that fraud on the part of LEF is very unlikely. Fraud on the part of a researcher from Africa who is head of his department…that’s a different story.
Oben says that the study referenced above was a “placebo-controlled crossover design,” and a “double blind randomised study.” But where is the crossover? I don’t see any evidence of it. And where is the randomness? In two random groups of 20 each, how can one have an initial cholesterol of 215 and the other 164? How can one have twice the initial HDL-c of the other? How can it be a blind study when one group is 30% heavier than the other from the start?
Not possible.
But the real question is, how could LEF not have noticed? If they are so sharp at finding fault with negative studies of vitamins and anti-oxidants, why were they so credulous here? If nothing else, this whole affair shows a complete lack of objectivity on the part of LEF.
I should also point out that, in Table 1 of Oben’s 2005 study, most of the measures of the “placebo” group didn’t change between weeks zero and two. Amost as if they weren’t meansured in week two. But if they weren’t measured, how did the researchers know who not to measure? How could it have been in a double blind study?
I’ve been using it for 1 1/2 weeks so far. I don’t refer to biological changes as miracles. I know must americans are hip to “miracles” and I think thats where mother goose comes to play. I don’t weigh myself so you won’t get any feed back from me there but I will say, my appetite seems to be more controllable. I am more calm and apt to eating less and using more discipline. Let’s see what 2 months will do. Hoodia didn’t do much for me, as far as appetite. PGX works well, but I’m liking the integra-lean so far. Theres more to it but irvingia does contain phosphalipids and phosphalipids cross the blood/brain barrier which seems to be an issue with most weight loss supplements. I’ve been combining it with NT Factor, which is another phosphalipid based, krebs cycle activating supplement for support every other day. Time will tell.
Jae, how is the weightloss going with Integra-Lean Irvingia? I just started it. Are you taking only 2 pills a day? It does not tell you when to take them before meals for the best affect.
Thanks for your help!
Donna
It has been a while since you started with Integra-Lean Irvingia, how has it worked for you? Any comments about it?
It didn’t work for me.
I agree with Lou and others who have observed that the active experimental and placebo control groups do not appear to be adequately randomized, and differ markedly in initial body weight, blood pressure and lipid status. The study published does not explain how subject randomization was performed.
Clearly the more overweight active experimental group would likely experience more weight loss. The placebo group was already at an optimal or suboptimal cholesterol level and ideally would not experience further cholesterol reductions.
The systolic blood pressure decrease in the active group was less than half of the systolic blood pressure decrease in the experimental group.
I also agree the standard errors of measurement from the mean are unusually high and may obscure differences produced by the herbal Irvingia treatment.
Results of the crossover phase of the study were ommitted from the published study. Age and sex demographics of the randomized groups were also ommitted from the publicized study and might help explain the large initial differences in the active and placebo groups.
This study does not appear to have received adequate peer review, prior to publication. Results reported in the study abstract appear to be only partially supported by the full study published at Lipids Health Dis. 2005; 4: 12.
Steven Sponaugle
Research Director,
Florida Detox and Wellness Institute
I have been taking Irvingia for about 3 weeks and suddenly my blood pressure is way too low. To be fair, I have to say I am on a beta blocker, metoprolol, but it wasn’t this low before. It’s sometimes as low as 75/45. Then I am unable to take the metoprolol which was needed to prevent arrythmias. So I am worried. Has anyone else’s blood pressure gone down so much?
Very nice information. Thanks for this.
Life Extension is a good organization. But they do not demand rigor from the studies they comb through. For example, they seem to see no difference between a double-blind, placebo-controlled study versus a simple observation of just one “treatment” group. There IS a difference. This goes hand in hand with their greatest flaw: their bias is that there are lots of beneficial supplements and treatments out there, that if the faintest hint of benefit is shown in even one poorly-designed observation, they’re all over recommending it.
Their recommendations are unlikely to cause harm, but the latest-and-greatest recommendations are likely to be a waste with less benefit than LEF anticipates. Their recommendations with more research backing and longer terms of study (e.g. CoQ10) are much more likely to be worth the money.
I was on this product Irvingia for more than 10 weeks and I believe it was not the reason for my weight loss. I believe I lost my weight because I lost my mind and workout 5xs a week killing myself. There were no changes in my energy levels, I was always tired I just forced myself to workout because I wanted to lose the weight so bad. No matter what LEF is claiming I was a consumer and it did not deliver for me at all. If that were the case, Ishould have lost more weight. I did everything they said to do, ate healthy food, cut out junk and exercised and took the Irvingia product. Companies say what they do to make money. The only way to lose weight is the old fashion way. PERIOD
Although this study does not appear to be adequately randomized, I should mention that I know two women who credit Irvingia for controlling their appetite, without any of the jitteryness or side effects of stimulants.
We are following a patient who is using the newer enhanced Irvingia, for weight loss.
I definitely agree with the previous poster that the ‘Disease Prevention and Treatment Book,” is very well written and researched. It is the best book of this type, I have found.
Steven Sponaugle
Research Director
Florida Detox and Wellness Institute
http://www.floridadetox.com
The study referenced here is the 2005 study. I agree, it is full of flaws. For what it is worth, the LEF article focuses more on the 2008 study. I don’t have a link for the new study, but here is a page that does provide a bit of information.
http://stanford.wellsphere.com/healthy-eating-article/more-information-on-irvingia/544189