You can buy them in any drugstore: slimming supplements containing fibre from the cactus Opuntia ficus-indica. You can see the plant in the drawing below. The supplements go by the name of Proactol, Prickly Pear Cactus or simply Opuntia. According to a sponsored human study, published recently in Current Therapeutic Research, the supplements may actually work. A little. A teeny weeny bit.
The researchers, who did contract research at a private laboratory in Germany, gave healthy subjects with a normal weight two tables containing Opuntia ficus-indica fibre twice a day after meals for a week. Each tab contained 500 mg fibre. On another occasion the researchers gave their subjects a placebo.
Before and during the supplementation the researchers measured the amount of fat in the subjects’ stools. The figure below shows that the Opuntia ficus-indica supplementation caused the amount of fat to rise.
When the subjects took a placebo they lost about 4.6 percent of the fat in their diet through excretion. When they took the Opuntia fibre this increased to 15.8 percent.
Expressed in grams this meant that the subjects lost 4.3 g fat if they took the placebo and 15.1 g fat if they took the supplement. That’s a difference of 10.8 g fat or 97 kcal per day.
Do the sums
If you burn 7000 kcal more than you consume you can lose 1 kg of body fat.
Opuntia, the weight-loss cactus
If you walk you burn 3.5 kcal per kg bodyweight each hour. So if you weigh 70 kg you lose the 97 kcal in just 24 minutes of walking.
Another example: jogging burns 7 kcal per hour per kg bodyweight. So if you weigh 70 kg you’ll burn the 97 kcal in just 12 minutes of jogging.
You can see why we’re sceptical.
The study was sponsored by InQpharm, the producer of the slimming supplement XLS Medical. This contains Opuntia ficus-indica fibre. Two of the authors of the study are also employees of InQpharm.
Effects of cactus fiber on the excretion of dietary fat in healthy subjects: a double blind, randomized, placebo-controlled, crossover clinical investigation.
Cactus (Opuntia ficus-indica) fiber was shown to promote weight loss in a 3-month clinical investigation. As demonstrated by in vitro studies, cactus fiber binds to dietary fat and its use results in reduced absorption, which in turn leads to reduced energy absorption and ultimately the reduction of body weight.
The objective of our study was to elucidate the dietary fat binding capacity of cactus fiber through determination of fecal fat excretion in healthy volunteers.
SUBJECTS AND METHODS:
This clinical investigation was performed as a double-blind, randomized, placebo-controlled, crossover study in healthy subjects for a period of approximately 45 days. Twenty healthy volunteer subjects were randomized to receive cactus fiber or placebo, 2 tablets thrice daily with main meals. All subjects were provided with meals during the study period (except washout) according to a standardized meal plan, with 35% of daily energy need coming from fat. Two 24-hour feces samples were collected during both the baseline and treatment periods for analysis of the fat content.
Cactus fiber showed an increased fecal fat excretion compared with placebo (mean [SD] = 15.79% [5.79%] vs 4.56% [3.09%]; P < 0.001). No adverse events were reported throughout the study period. CONCLUSIONS: Cactus fiber has been shown to significantly promote fecal fat excretion in healthy adults. The results of our study support the hypothesis that cactus fiber helps in reducing body weight by binding to dietary fat and increasing its excretion, thus reducing dietary fat available for absorption. ClinicalTrials.gov identifier: NCT01590667. PMID: 25067985 [PubMed] PMCID: PMC4109417 Source: http://www.ncbi.nlm.nih.gov/pubmed/25067985/