Chromium picolinate is a dietary supplement that can be used as to increase body weight, so to decrease it. It enhances insulin effect, and it is called the “glucose tolerance factor”. In a randomized double-blind clinical trial, male and female students, enrolled for a 12-week body weight optimization program, were randomly assigned to receive either 200 g of chromium picolinate per day, or placebo.
Although every group showed slight increase in waist circumference and decrease in skin fold thickness, the only statistically significant difference concerning increase in body weight was observed to a larger extent in women receiving chromium picolinate as compared to other 3 groups of patients. These results were supported during the study conducted by Grant et al., that involved 43 obese women receiving 400 g of chromium picolinate per day. Increase in body weight was observed only until initiation of regular physical activity that promoted decrease in body weight and glucose-mediated insulin secretion.
In the study conducted by Pasman et al., body weight dynamics was compared between 200 g of chromium picolinate per day, or dietary fibers, caffeine, or 50 g of carbohydrates per day in 33 patients suffering from obesity. During the first two months, the participants were on a very low-calorie diet. It was revealed that administration of chromium picolinate didn’t have any impact on body weight. Walker et al., compared 200 g of chromium picolinate per day with placebo in terms of their effect on body weight and physical activity, if taken by 20 wrestlers during 14 weeks. Similar results were obtained by Campbell et al., during administration of 200 g of chromium picolinate per day by 18 men aged from 56 to 69 years who were engaged in physical fitness program requiring training equipment; the studies revealed no impact on body weight and force of the participants.
Animal tests for toxicity showed that there is a wide therapeutic dose range of food supplements containing chromium, but chromium picolinate doesn’t in any way affect human body composition, so it is absolutely ineffective as a treatment option for obesity.
Chitosan is acetylated chitin found in the exoskeleton of crustaceans (mainly in shellfish). Its use was suggested for the purposes of lipid binding (including cholesterol and triglycerides) in human intestine; it acts as a “fat-blocking agent”, and that is why administration of chitosan for weight reduction purposes seems quite justified. If chitosan is mixed with vegetable oil in a jar of water, it will absorb oil and precipitate, forming clear emulsion. This experiment is often used to prove the ability of chitosan to block fat absorption in the digestive tract and prevent obesity. It is promised to the patients that even if they don’t restrict fatty food intake, they still won’t experience body weight gain.
Efficacy of chitosan was studied in the course of two double-blind clinical trials. The participants were assigned to oral administration of 1200-1600 mg of chitosan 2 times per day. In the first trial, 51 obese female patients received the drug during 8 weeks; but their body weight didn’t reduce. In the second trial, 34 obese male and female patients received chitosan during 28 days; no dynamics in body weight optimization was seen either as compared to control group. In both trials, neither harsh side effects, nor any influence on metabolism of fat-soluble vitamins and iron was detected. It is possible that chitosan can reduce body weight by binding food lipids in the intestine, but it is not effective in recommended dosages.
As for the weight-loss medicine, ephedra alkaloids are the most widely used agents (ma huang preparation); it is believed that administration of such drugs ensures increase in energy consumption, which, in its turn, helps to reduce body weight. Recently, the information concerning side effects of such drugs came to light, and the FDA USA limited their dosages and duration of their administration.
Distribution of herb mixtures, containing caffeine, used for weight loss has become a tremendous industry. Caffeine found in phytopreparations has practically the same chemical composition as caffeine contained in pharmacological substances. Data from experimental studies in animals and people confirm the ability of caffeine to decrease body weight by activating oxygen consumption and fat oxidation.
Caffeine has been traditionally used in food supplements to treat headache and fatigability; its safety has been established. The FDA USA legalized sale of caffeine without prescription to people who reached 12 years of age as a stimulating agent (administration of up to 200 mg every 3 hours – 1600 mg/day) and as part of analgesics.
In a recent three-month study, the effect of 25 mg and 50 mg ephedrine three times a day was compared to that of placebo. The rate of weight loss was comparable between two dosages, but the incidence of adverse events (increase in blood pressure and heart rate, excitement, insomnia, headache, weakness, heartbeats, dizziness, euphoria, tremor, diarrhea) was higher with 10 mg of ephedrine a day than with placebo. At the end of the first and the second month, weight loss was more marked in the caffeine-treated group, but at the end of the third month the difference completely disappeared.
In a 24-week double-blind trial, the patients suffering from obesity were randomly assigned to receive 20 mg of ephedrine; 200 mg of caffeine; a combination of 20 mg of ephedrine and 200 mg of caffeine; or placebo 3 times/day. In ephedrine/caffeine combination therapy, body weight of patients started to decrease at week 8 and continued to reduce up to the very end of the follow-up period (17.5%); the results of ephedrine/caffeine monotherapies weren’t much different from the result of placebo administration. The incidence of adverse events (tremor, insomnia, dizziness) and arterial hypertension at week 8 was comparable between the groups. Two weeks after dechallenge, headaches and fatigability were observed more often in the combination therapy group. The participants were further enrolled in a 24-week follow-up study of caffeine and ephedrine, provided that the participants were aware of the drug they received. At week 50, body weight reduction persisted in ephedrine/caffeine combination group; anorexia is thought to account for 75% of this effect, while thermogenic activation explains the other 25%.
The studies were conducted to explain the mechanism of action of ephedrine in humans. Although it activates thermogenesis in rodents’ multilocular adipose tissue, such tissue is found in humans only to a certain extent, which explains the reasons why the effect of ephedrine is observed mostly in skeletal muscles. It was revealed that ephedrine decelerates gastric transit of food, which can account for anorexia development.
Ephedrine is traditionally available without prescription for treatment of bronchial asthma, while caffeine is used for drowsiness management. No toxic reactions were observed even in doses exceeding therapeutic dosages in phytopreparations containing ephedrine and caffeine, which are used for body weight reduction. In treatment of bronchial asthma, it is recommended to take 15 mg of ephedrine a day and 1600 mg of caffeine a day. In order to reduce body weight, no more than 100 mg of phytopreparations containing caffeine and ephedrine should be taken per day on pure ephedrine basis. Content of caffeine in phytopreparations varies, but the daily dosage doesn’t exceed 600 mg. Administration of the most preferred phytopreparations stipulates that only 240 mg of caffeine per day enters the body (which is equal to 3 cups of coffee).
It is possible that abundance of obesity in industrially developed countries observed since 1990 is caused by alteration of dietary fiber composition: the percentage of dietary fibers consumed with starch-containing products decreased, while the percentage of fibers consumed with fruits and vegetables increased. The studies aimed at evaluation of interaction between the content of dietary fibers in food and body weight have been conducted since 1980. It was demonstrated that guar gum (water-soluble fibers) reduces the feeling of hunger and helps to manage body weight in a more efficient way than insoluble bran fiber, even in the absence of a special-purpose diet.
Relation between obesity and administration of dietary fibers was also assessed in epidemiological studies. When food intake frequency was studied using questionnaires, it was demonstrated that a diet developed for obese men contained more fat and less dietary fibers than the diet developed for men and women who are not experiencing obesity. In people with normal body weight, total consumption of dietary fibers was higher; the amount of dietary fibers on a 1000 kcal basis turned out to be in inverse proportion to the body mass index.
It has been proved that consumption of dietary fibers leads to decrease in total food volume, reducing the feeling of hunger; efficacy of water-soluble fibers is, probably, higher than efficacy of water-insoluble fibers. Administration of food supplements containing dietary fibers (5-40 g/day) ensures slight body weight loss (1 to 3 kg) more often than administration of placebo. Although weight reduction doesn’t reach 5% (the minimum effective therapeutic value), safety of administration of dietary fibers and their considerable positive impact on cardiovascular risk factors impel to add them to the weight-loss diets.
Garcinia cambogia contains one of 16 isomers of citric acid – hydroxycitric acid obtained from gamboge fruits. It is the only substance capable of inhibiting citrate-lyase – the enzyme catalyzing the first non-mitochondrial stage of fatty acid synthesis. Efficacy and safety of hydroxycitric acid was studied in a series of clinical trials. Administration of 500 mg of Garcinia cambogia extract and 100 g of chromium picolinate 3 times per day was evaluated in an 8-week open clinical trial. At the end of the study, body weight of women decreased by 5.5%, and in men it reduced by 4.9%.
In the course of another cross-over clinical trial, 10 male patients were enrolled in order to evaluate energy consumption and intensity of body substrate oxidation. No differences were detected in respiratory quotient, energy consumption, the levels of glucose, insulin, glucagon, lactate, ß- hydroxybutyrate under rest or stress conditions.
The third randomized double-blind clinical trial (135 adult patients suffering from obesity; a high-fiber low-fat diet; a 12-week follow-up period) compared administration of 1500 mg of hydroxycitric acid per day with placebo; the rate of weight loss was comparable. On today’s market one can find a green food supplement containing hydroxycitric acid calcium salt; for the purposes of obesity treatment, its dosage should not exceed 3 g per day. In the course of experiments with rodents, it was shown that sodium hydroxycitric acid salt reduces the amount of consumed food and body fat percentage having no impact on protein metabolism. There is every reason to believe that inefficiency of hydroxycitric acid preparations in humans is associated either with insolubility of calcium salt, or with species differences between rodents and humans. It is necessary to conduct further investigations to solve the matter. As of today, it is possible to declare that food supplements containing vegetable-grade hydroxycitric acid have no impact on human obesity.
Green Tea Catechins
Green tea is made from leaves of the Camelia sinensis plant that were steamed and dried immediately after their collection. In Asia, they drink green tea all the time. Black tea is produced by enzymatic autoxidation of Camelia sinensis leaves, whereby catechins are almost completely transformed into tea flavins. Catechins belong to the family of substances containing a potent antioxidant – epigallocatechin gallate (EGCG). Catechins also activate adrenoreceptors of adipose cells, which might enhance sympathetic effect.
Since green tea extracts contain caffeine, it is difficult to distinguish between the impact of green tea and caffeine. In a study conducted by Dulloo et al., participants received green tea extract 3 times a day in the form of capsules containing 150 mg of caffeine and 375 mg of catechins (including 270 mg of EGCG); or 150 mg of pure caffeine; or they took placebo, and then they were kept in a calorimetric chamber for 3 days. Energy consumption in the first group was by 3.2% higher than in the second group, and by 4.5% higher than in the third group. Lipid oxidation was observed simultaneously. In general, administration of green tea increased energy consumption by 80 kcal per day. It is evident that the effect of green tea catechins alone is rather hard to define since there is a possibility of their synergetic interaction with ephedrine that is not dependent on caffeine. The last sentence requires further specification.
ß-hydroxybutyrate is a leucine metabolite used as a “fat burner” that induces muscle building and enhances muscular strength. According to the study conducted by Nissen et al., supplementary administration of 1.5-3 g of ß-hydroxybutyrate per day in the context of a body weight gaining program (2-6 weeks) decelerates catabolism in muscles and increases body weight (except for adipose tissue weight). However, such effect wasn’t seen in trained sportsmen. Although the trials conducted for 3-8 weeks established the safety of supplementary administration of ß- hydroxybutyrate, there is no evidence supporting the rationale of its use for the treatment of obesity.