About five years ago we wrote a piece on the slimming supplement Sinetrol, about the fact that it could help you lose up to half a kilogram a week. And it’s not based on suspect stimulants – the active ingredients are polyphenols from citrus fruits. According to a recent human study, Sinetrol is safe – and may even have a mild muscle-building effect.
Sinetrol is manufactured by the French company Fytexia, which is owned by Constantin Dallas, the first author of both the new study and the previously published one on the effect of Sinetrol. Despite this, at the end of the article there’s a sentence that states, “the authors declare no conflict of interest”. Well, you should take that with a grain of salt: this is a sponsored study.
Dallas gave just under a hundred healthy but overweight subjects information on a gentle calorie-reduced diet and recommended they exercise for at least half an hour every day. Half of the subjects also took Sinetrol for 12 weeks; the other half took a placebo.
Sinetrol contains no stimulants like synephrine or octopamine. It’s made from the peel of citrus fruits, and is rich in phenols. The subjects took 450-mg capsules at breakfast and lunch every day. So in total they consumed 900 mg Sinetrol a day. The trial lasted 12 weeks.
The subjects in the Sinetrol group lost more weight and more fat than the subjects in the placebo group.
In terms of change in body composition, the Sinetrol users lost about 3.7 kg fat and the placebo takers only 1.4 kg.
At the same time the lean body mass of the Sinetrol users should have increased by about 1.1 kg.
(Look at that! There’s another one for the Unusual Muscle Building Strategies.)
The supplement had almost no side effects, although the subjects’ heart rate increased slightly and there was a sharp increase in free fatty acids in their blood.
The latter is probably a consequence of the enzyme PDE in the fat cells being inhibited by the citrus phenols. This leads to an increase in the concentration of the second messenger cAMP, which means the fat cells listen better to pep hormones like adrenalin. These are the hormones that induce fat cells to release their contents into the bloodstream.
In the Sinetrol group the concentration of the antioxidant enzyme SOD rose, as did that of glutathione [GSH], a peptide that detoxifying enzymes need. The concentration of malondialdehyde [MDA], a marker for free radical activity, decreased.
The researchers also looked at the effect of Sinetrol on liver and kidney function, insulin sensitivity, cholesterol and blood pressure, but found no noticeable effects.
“We suggest that consumption of Sinetrol-XPur produces beneficial changes in body fat composition and improves inflammatory, glycemic, and oxidative status in overweight healthy individuals”, they conclude. “When taken twice a day for 12 weeks, Sinetrol-XPur supplement was well tolerated with no adverse effects. However, additional research is warranted to delve deeper into the mechanisms of action and confirm these results over a longer period.”
Clinical study to assess the efficacy and safety of a citrus polyphenolic extract of red orange, grapefruit, and orange (Sinetrol-XPur) on weight management and metabolic parameters in healthy overweight individuals.
The present study investigated the efficacy and safety effects of Sinetrol-XPur (polyphenolic citrus dry extract) in weight management; metabolic parameters; and inflammatory, glycemic and oxidative status. In a 12-week, randomized, double-blind, placebo-controlled trial, Sinetrol-XPur was given to overweight subjects twice daily with meals in the tested group (N?=?47) versus a placebo group (N?=?48). Waist and hip circumference and abdominal fat were decreased in the Sinetrol-XPur group as compared with the placebo group (p?< ?0.0001) (-5.71% vs. -1.56% for waist, -4.71% vs. -1.35% for hip and -9.73% vs. -3.18% for fat). Inflammatory markers were reduced (C-reactive protein: -22.87% vs. +61%; fibrinogen: -19.93% vs. -1.61%, p?0.01). Oxidative stress was lowered as seen by the reduction of malondialdehyde (-14.03% vs. 2.76%) and the increase in superoxide dismutase and glutathione (17.38% vs. 2.19% and 4.63% vs. -2.36%, respectively, p?0.01). No adverse effects were observed. Kidney, liver, and lipid panels remained unchanged. These results indicated that Sinetrol-XPur supplementation is a viable option for reducing abdominal fat, waist and hip circumference, and body weight and for improving inflammatory, glycemic, and oxidative status in healthy overweight individuals.
PMID: 23554029 [PubMed - indexed for MEDLINE]