Plant Part Used
Fruit
Active Constituents
(-)-hydroxycitric acid. (1)
[span class=alert]This section is a list of chemical entities identified in this dietary supplement to possess pharmacological activity. This list does not imply that other, yet unidentified, constituents do not influence the pharmacological activity of this dietary supplement nor does it imply that any one constituent possesses greater influence on the overall pharmacological effect of this dietary supplement.[/span]
Introduction
The use of garcinia cambogia has been growing rapidly in the United States due to the desire of people to lose weight. The United States has the most obese population in the world, and many Americans would love to find “magic bullets” for weight loss. However, individuals must realize that the cornerstone to good health is wise food selection and exercise. If these are coupled with good ergogenic (metabolic enhancing) products, then success at maintaining proper weight is more likely to be long lasting, because it will become a lifestyle. Unlike appetite suppressant drugs, garcinia has no CNS stimulant activity. Preliminary research indicates that it may modulate blood fat levels and have a positive effect on energy and metabolism.(2),(3)
Interactions and Depletions
Interactions
Dosage Info
Dosage Range
500-1000mg (standardized extract), 3 times a day, taken 1/2 hour before meals.
Most Common Dosage
500mg (standardized extract), 3 times a day taken 1/2 hour before meals.
Standardization
[span class=doc]Standardization represents the complete body of information and controls that serve to enhance the batch to batch consistency of a botanical product, including but not limited to the presence of a marker compound at a defined level or within a defined range.[/span]
No true standardization; but 50% (-)-hydroxycitric acid [(-)-HCA] content per dose is desired.
Uses
Frequently Reported Uses
- Insulin Regulation
- Weight Management
Other Reported Uses
- Elevated Cholesterol
Toxicities & Precautions
General
No known toxicity.(4)
Health Conditions
There have been several case reports of hepatotoxicity when using proprietary supplements for weight loss that contain Garcinia cambogia.(15),(16) However, some of the supplements that contributed to hepatotoxicity did not contain hydroxycitric acid, the constituent found in Garcinia cambogia.(17) Proprietary weight loss formulations can contain up to 20 different ingredients. Until further research is performed, it is not recommended to use Garcinia supplements in individuals with pre-existing liver disease or at risk for liver disease with extreme caution.
There was a case report of an 18 year old Caucasian male admitted to an emergency room with acute rhabdomyolysis (serum creatinine kinase was 13,220 IU/L).(18) The patient had been taking Hydroxycut, a formulation containing hydroxycitric acid from Garcinia. The patient was also on multiple prescription medications. When Hydroxycut was discontinued along with hydration and decreased exercise, his CK and liver enzymes returned to normal after 2 weeks.
Pregnancy/ Breast Feeding
If pregnant or nursing, consult a physician before use.
Age Limitations
Do not use in children under 2 years of age unless recommended by a physician.
Pharmacology
The appetite-suppressant mechanism of Garcinia is thought to be due in part to the production of glycogen in the liver and small intestine.(5) The conversion of carbohydrates to fat requires the enzyme, adenosine triphosphate citrate lyase. Garcinia temporarily inhibits this enzyme.(6) At the same time, the liver produces more glycogen and this sends a satiety signal to the brain. Obese individuals have less glycogen storage and more triglyceride storage than thin individuals. The storage mechanism for glycogen in the peripheral muscle tissue is thought to be defective in obese and patients with Type 2 diabetes. Studies have reported that individuals using Garcinia, combined with niacin-bound chromium and a reduction in dietary fats, had three times the weight loss of those on diet alone.(7)
Obesity is often seen in individuals with diets high in refined foods and saturated fat. In one study, the acute and chronic effects of (-)-hydroxycitric acid (HCA) on energy metabolism was studied in laboratory animals.(8) The results suggested that chronic administration of HCA may promote lipid oxidation and spare carbohydrate utilization at rest and during physical activity. A double-blind, placebo-controlled parallel group study in 89 mildly overweight female subjects tested the effectiveness of HCA in weight loss.(9) Forty-two participants ingested 400-mg caplets of Garcinia 30-60 min prior to meals for a total dose of 2.4 g/day (equivalent to 1.2 g/day of HCA), with forty-seven participants ingesting placebos.The HCA treatment group did not exhibit better dietary compliance, significant appetite changes, an increase in energy intake or weight change. Another recent study reported no benefits in the management of obesity in human subjects when given 1500mg Garcinia per day.(10)
However, other authors have commented on this clinical study reported by Heymsfield, et al in 1998, reporting that many factors may have caused the human clinical trial to report results that did not support the use of HCA in weight loss. One report states that for HCA to effectively inhibit fat formation and body weight, it needs to be administered with a simple carbohydrate-rich (lipogenic) diet.(11) Some laboratory and clinical studies report hydroxycitric acid has antilipolytic and antiadipogenic effects.(19) A clinical study did not find any sex hormonal activity when using Garcinia.(20) The use of a high-fiber diet in combination with HCA may reduce gastrointestinal absorption of HCA, since high-fiber diets may reduce absorption of many nutrients and micronutrients. This pharmacological issue is important due to the inhibition of the intracellular enzyme adenosine triphosphate(ATP)–citrate-lyase depending entirely on the presence of HCA inside the target cell. The conversion of citrate to acetyl-CoA by ATP–citrate-lyase occurs only when the rate of glycolysis exceeds the energy requirements of the body, and the low-energy diet used in the human study may have negated the utility of HCA.(12) Also, the dose of HCA used in the study was low compared with that used in earlier successful animal trials, and bioavailability may have been reduced.(13) Excessive levels of calcium (used to stabilize the HCA molecule), high levels of naturally occurring pectin, and low solubility in water are factors that can also reduce bioavailability – and there are products on the market which do not meet specifications necessary for proper bioavailability of HCA.(14) A compound complexes with calcium and potassium is nearly 100% soluble and creates a pH level that is favorable for maximum gastrointestinal absorption. A soluble Garcinia powder and liquid extract containing a lactone form of HCA was compared with a calcium-type Garcinia powder administered in food to rats, and the liquid extract was proven more effective.(14) Continued research needs to be performed to determine if the use of HCA is warranted in weight loss protocols.
References
- Sullivan AC, et al. Inhibition of Lipogenesis in Rat Liver by (-)-hydroxycitrate. Arch Biochem Biophys. 1972;150(1):183-90.
- Sergio W. A Natural Food, the Malabar Tamarind, May Be Effective in the Treatment of Obesity. Med Hypotheses. 1988;27(1):39-40.
- Sullivan AC, et al. Effect of (-)-Hydroxycitrate upon the Accumulation of Lipid in the Rat. II. Appetite. Lipids. 1974;9:129-34.
- Lowenstein JM, et al. Effect of (-)-Hydroxycitrate on Fatty Acid Synthesis by Rat Liver in Vivo. J Biol Chem. 1971;246:629-32.
- View Abstract: Sullivan AC, et al. Metabolic Regulation as a Control for Lipid Disorders. I. Influence of (–)-hydroxycitrate on Experimentally Induced Obesity in the Rodent. American J of Clinical Nutrition. 1977; 30:767-76.
- McGarry JD, et al. In Support of the Roles of Malonyl-CoA and Carnitine Acyltransferase I in the Regulation of Hepatic Fatty Acid Oxidation and Ketogenesis. J Biol Chem. 1979;254:8163-68.
- View Abstract: McCarty MF, et al. Inhibition of Citrate Lyase May Aid Aerobic Endurance. Med Hypotheses. 1995;45(3):247-54.
- View Abstract: Ishihara K, Oyaizu S, Onuki K, et al. Chronic (-)-Hydroxycitrate Administration Spares Carbohydrate Utilization and Promotes Lipid Oxidation During Exercise in Mice. J Nutr. Dec2000;130(12):2990-5.
- View Abstract: Mattes RD, Bormann L. Effects of (-)-Hydroxycitric Acid on Appetitive Variables. Physiol Behav. Oct2000;71(1-2):87-94.
- View Abstract: Heymsfield SB, et al. Garcinia cambogia (hydroxycitric acid) as a Potential Anti-obesity Agent: A Randomized Controlled Trial. JAMA. Nov1998;280(18):1596-600.
- Badmaev V, Majeed M, Conte AA. Garcinia cambogia for Weight Loss. JAMA. Jul1999;282(3):233-4.
- Schaller JL. Garcinia cambogia for Weight Loss. JAMA. Jul1999;282(3):234.
- Sullivan AC, Triscari J, Hamilton JG, et al. Effect of (-)-Hydroxycitrate Upon the Accumulation of Lipid in the Rat, I: Lipogenesis. Lipids. 1974;9:121-128.
- Sawada H, Tomi H, Tamura K, et al. Effects of Liquid Garcinia Extract and Soluble Garcinia Powder on Body Weight Change: A Possible Material for Suppressing Fat Accumulation. Nihon Yukagaku Kaishi. 1997;46:1467-1474.
- Lobb A. Hepatoxicity associated with weight-loss supplements: a case for better post-marketing surveillance. World J Gastroenterol. 14 Apr 2009;15(14):1786-1787.
- Shim M, Saab S. Severe hepatotoxicity due to Hydroxycut: a case report. Dig Dis Sci. Feb 2009;54(2):406-408. Epub 2008 Jul 26. No abstract available.
- Stohs SJ, Preuss HG, Ohia SE, et al. No evidence demonstrating hepatotoxicity associated with hydroxycitric acid. World J Gastroenterol. 28 Aug 2009 ;15(32):4087-4089.
- Dehoney S, Wellein M. Rhabdomyolysis associated with the nutritional supplement Hydroxycut. Am J Health Syst Pharm. 15 Jan 2009;66(2):142-148. Erratum in: Am J Health Syst Pharm. 15 Feb 2009;66(4):328. Dosage error in article text.
- Roy S, Shah H, Rink C, Khanna S, Bagchi D, Bagchi M, Sen CK. Transcriptome of primary adipocytes from obese women in response to a novel hydroxycitric acid-based dietary supplement. DNA Cell Biol. Sep 2007;26(9):627-639.
- Hayamizu K, Tomi H, Kaneko I, Shen M, Soni MG, Yoshino G. Effects of Garcinia cambogia extract on serum sex hormones in overweight subjects. Fitoterapia. Jun 2008;79(4):255-261. Epub 2008 Feb 9.
