Hydroxycitric Acid for Weight Control
How much is usually taken by dieters?
HCA, extracted from the rind of the Garcinia cambogia fruit grown in Southeast
Asia, has a chemical composition similar to that of citric acid (the primary acid in oranges
and other citrus fruits). Preliminary studies in animals suggest that HCA may be a useful
weight-loss aid.1 2 HCA has been demonstrated in the laboratory (but not
yet in clinical trials with people) to reduce the conversion of carbohydrates into stored fat
by inhibiting certain enzyme processes.3 4 Animal research indicates
that HCA suppresses appetite and induces weight loss.5 6 7
8 However, a double-blind trial found that people who took 1,500 mg per day of HCA
while eating a low-calorie diet for 12 weeks lost no more weight than those taking a
placebo.9 A double-blind trial of Garcinia cambogia (2.4 grams of dry
extract, containing 50% hydroxycitric acid) found that the extract did not increase energy
expenditure; it was therefore concluded that this extract showed little potential for the
treatment of obesity at this amount.10 Nonetheless, another double-blind trial
found that using the same amount of Garcinia cambogia extract significantly improved
the results of a weight-loss diet, even though the amount of food intake was not
affected.11
References
1. Lowenstein JM. Effect of (-)-hydroxycitrate on fatty acid synthesis by
rat liver in vivo. J Biol Chem 1971;246:629–32.
2. Triscari J, Sullivan AC. Comparative effects of (-)-hydroxycitrate and
(+)-allo-hydroxycitrate on acetyl CoA carboxylase and fatty acid and cholesterol synthesis in
vivo. Lipids 1977;12:357–63.
3. Cheema-Dhadli S, Harlperin ML, Leznoff CC. Inhibition of enzymes which
interact with citrate by (-)hydroxycitrate and 1,2,3,-tricarboxybenzene. Eur J
Biochem 1973;38:98–102.
4. Sullivan AC, Hamilton JG, Miller ON, et al. Inhibition of lipogenesis
in rat liver by (-)-hydroxycitrate. Arch Biochem Biophys 1972;150:183–90.
5. Greenwood MRC, Cleary MP, Gruen R, et al. Effect of (-)-hydroxycitrate
on development of obesity in the Zucker obese rat. Am J Physiol
1981;240:E72–8.
6. Sullivan AC, Triscari J. Metabolic regulation as a control for lipid
disorders. Am J Clin Nutr 1977;30:767–76.
7. Sullivan AC, Triscari J, Hamilton JG, et al. Effect of
(-)-hydroxycitrate upon the accumulation of lipid in the rat: I. Lipogenesis. Lipids
1974;9:121–8.
8. Sullivan AC, Triscari J, Hamilton JG, et al. Effect of
(-)-hydroxycitrate upon the accumulation of lipid in the rat: II. Appetite. Lipids
1974;9:129–34.))
9. Heymsfield SB, Allison DB, Vasselli JR, et al. Garcinia
cambogia (hydroxycitric acid) as a potential antiobesity agent: a randomized controlled
trial. JAMA 1998;280:1596–600.
10. Martinet A, Hostettmann K, Schultz Y. Thermogenic effects of
commercially available plant preparations aimed at treating human obesity.
Phytomedicine 1999;6:231–8.
11. Mattes RD, Bormann L. Effects of (-)-hydroxycitric acid on appetitive
variables. Physiol Behav 2000;71:87–94.