an autodidact meets a dilettante…

just add water and you get stuffed, apparently

The ‘obesity epidemic’ has been big news in the west for some time now. Increasing affluence, increased food production, the popularity of junk food and sugar-laden soft drinks, the pressure of advertising, not to mention the popularity of computer games and activities that exercise only the finger muscles, all have contributed to the rise and rise of western flab, and associated health problems.

Naturally, all sorts of solutions, of varying quality, are being offered, from lap banding to any number of diets, from crash fads to the more or less scientific. Clearly there’s the potential for a lot of money to be made in this area. Crisis can always be spelt as ‘opportunity’.

So it was with some interest that I noted an ad on TV the other day, from the company Swisse. From memory [that very unreliable source] it featured an attractive thirty-something woman, telling us of her busy day and how it was important to stay in trim, and recommending the use of Swisse ‘appetite suppressant’ pills. She also mentioned that the pills, or their active ingredients, were derived from a cactus plant which was used for this purpose for thousands of years by the natives of wherever the cactus grew. I don’t think the location was specified.

Well, I fell to wondering. A pill that suppresses your appetite, so that you’re less hungry and therefore eat less on a daily basis. Isn’t this the solution to the obesity crisis? Well, maybe not the solution, as there’s still the matter of what you eat, and how active you are, but certainly a general purpose appetite suppressant would be a great weapon in the fight against flab, and probably the primary weapon. Surely this is nothing short of sensational. Worthy of headline news at least.

So let’s see what I can learn about this appetite suppressant and how it works. As a seasoned researcher, I accessed that unmatchable research tool, google, and clicked the first link to come up in the list under ‘Swisse appetite suppressant’. It took me, of course, to the Swisse website, where I found a useful summary, from their perspective:

Swisse Ultiboost Appetite Suppressant contains Slimaluma®, a premium quality ingredient to help reduce hunger levels. Slimaluma® is a naturally derived extract of the cactus plant which has been used for centuries in India for its appetite suppressant qualities when food was scarce. Swisse Ultiboost Appetite Suppressant can be used to help control hunger levels and is best combined with healthy eating and as part of a regular exercise regime.

The advice at the end is admirable, though I do wonder whether people who engage in healthy eating and regular exercise are in need of an appetite suppressant. Healthy eating presumably already excludes over-eating. I was also interested in, and on reflection, slightly disturbed by the offhand remark ‘when food was scarce’. After all, to take away or reduce the pangs of hunger when you’re hungry, or even starving, is a bit like giving a painkiller. It reduces the symptoms but doesn’t solve the problem. It could even exacerbate it, when you consider that feeling hungry is nature’s or evolution’s way of telling you that you need to eat. I wondered how such a product could translate to use in an over-indulgent food-abundant society.

In any case we now find that the cactus plant hails from India and that the active ingredient extracted from it is called ‘Slimaluma’. So how effective is Slimaluma and how does it work?

My search took me to the website of Gencor Pacific, the makers of Slimaluma, and here’s what they have to say:

SLIMALUMA™ is a proprietary standardized extract of Caralluma Fimbriata, an edible plant used for centuries in India as a famine food and appetite suppressant. Gencor Pacific has developed a unique patented process to extract the essential constituents of the whole herb without chemical alteration to any of the key constituents, ensuring that the full benefits of the herb are delivered in concentrated form.

Caralluma fimbriata

Sounds impressive, and there’s more. They describe the results of clinical testing of the product, which is a great sign at least:

SLIMALUMA™ has undergone two double blind, randomized, placebo controlled human clinical trials, one in India and the other in California, USA. Many participants experienced significant loss in appetite and some lost inches off their waist and hips. Participants also experienced reduction in body weight and body fat.

They then link to a more detailed description of the studies and their findings, which again is excellent, and much more than we’ve learned to expect from the sellers of ‘natural’ health products. However, for obvious reasons it would be unwise to simply accept the description and interpretation of the studies of a health product by the makers of that product. So we need to look at more than one, possibly multiple descriptions and interpretations of the studies, and at whether other studies have been conducted.

So let’s look at clinical trial number one. It was conducted at the Division of Nutrition, St John’s National Academy of Health Sciences, Bangalore India during January to August 2003, and it involved 50 subjects. The Wikipedia article on Caralluma fimbriata [and I find Wikipedia quire reliable on these matters in spite of its reputation in some circles] reports on this trial rather differently:

In a small clinical trial conducted in India, modest benefits of Caralluma fimbriata extracts were observed. In the study, 50 overweight individuals were given either a placebo or one gram of extract each day for 60 days. Compared to the placebo group, individuals receiving the extract showed no significant change in body weight, body mass index, hip circumference, body fat or energy intake; however, both appetite and waist circumference were reduced

The difference in these descriptions of the same trial naturally demands that we examine those descriptions more closely. In Slimaluma’s description we’re told that ‘many’ participants experienced ‘significant loss in appetite’. Two questions here – first, how many is many? Fifteen, thirty-five? What about a percentage? And second, how do you measure ‘significant loss of appetite’? Weight loss and BMI are easy to measure objectively, but not appetite loss. I can only imagine that it’s measured through reporting, which, however unreliable, can at least be measured against the reporting of the placebo group. So, while the term ‘significant’ here is a bit tricksy, let’s accept that there was discernible appetite loss. Fine, but the findings were that this change did not lead to reduction in ‘energy intake’, meaning that the Slimaluma consumers didn’t eat less, in spite of having reduced appetite. An odd finding. Not only that, they didn’t reduce body weight or BMI, though there was a reduction in waist circumference. In other words the results seem to be all over the place, and of course the Slimaluma manufacturers only reported, and hyped, the positive findings.

The Indian study was quite small, and its results were hardly definitive. Shannon Moffett, in her book about the brain, The Three-Pound Enigma, which I just happened to be reading today, makes a general statement about research which fits nicely here:

..when you make a generalisation from the sample you study to the population at large, there is a chance – bigger or smaller depending on factors like the size of your sample compared to the size of the population as a whole, how well you controlled for other variables, and so forth – that the trend or trait you observed is characteristic only of that sample and not of the population at large

I seem to remember Steven Novella saying that 50 was an okay number for a study of this kind, if a bit on the small side. It would certainly be useful if it was backed up by further research, but really the initial findings are so underwhelming that further funding might be hard to find. One might expect that there would be some weight loss for the whole group over the six-month research period, as they were all obese and knew they were being studied for weight loss. They were advised not to change their diets, but it’s likely they would have. I haven’t been able to find the precise data on the study, as it’s behind a paywall [why?], but there was a further study done. However, it involved only 26 subjects, only 7 of whom were given placebos. This study only lasted for four weeks [an absurdly short period, it seems to me, given the notorious ‘rebound effects’ of people on diets]. As presented in this Gencor gloss on both studies, it produced ‘excellent’ results, but the sample was too small and the research period too short to produce reliable data.

The gloss mentioned above does attempt some science on the action of Caralluma fimbriata’s phytochemical constituents – pregnane glycosides, fIavone glycosides, megastigmane glycosides and saponins – in suppressing appetite, but I can find very little in the mainstream literature on these specific phytochemicals. The fact is, there’s very little scientific evidence for the efficacy of this product, and the Wikipedia article mentioned above makes this very important point.

Various diet pills claiming to contain Caralluma fimbriata extracts are marketed for weight loss. However there is no independent evidence to suggest that the amount of extract found in these products is sufficient to obtain the same results as the clinical trial. The FTC cautions against the use of “miracle diet” products.

This is a major problem with all so-called allopathic products. There is no control or oversight to their manufacture, as there is with all prescription medication. And, let’s face it, if these appetite suppressants really were efficacious, they would become prescription treatments. That’s what happens with evidence-based medicine. So chuck out those pills, eat less, eat healthily, and make sure you get plenty of exercise. There really is no alternative.