Hydroxycitric acid's therapeutic uses
Hydroxycitric acid (HCA) is a natural compound primarily derived from the Malabar tamarind fruit, known scientifically as Garcinia cambogia. It has been studied for its potential therapeutic uses, notably in weight loss and the prevention of kidney stones. While some animal and laboratory studies suggest that HCA might aid in weight loss by influencing metabolism and appetite, human clinical trials have produced mixed results, indicating that its effectiveness in this area remains uncertain. Additionally, HCA shows promise in reducing kidney stone formation by preventing calcium oxalate crystals from adhering to kidney walls, though more research is needed to confirm these benefits.
HCA is commonly consumed in various supplement forms, with recommended dosages ranging from 250 to 1,000 mg taken three times daily. Although considered safe in moderation, there are some safety concerns, particularly for specific populations, including pregnant or nursing women and individuals with certain medical conditions or on specific medications. Overall, while HCA is often promoted in the complementary and alternative medicine community for its potential health benefits, further clinical research is necessary to fully understand its efficacy and safety.
Hydroxycitric acid's therapeutic uses
DEFINITION: Natural plant product used to treat specific health conditions.
PRINCIPAL PROPOSED USES: None
OTHER PROPOSED USE: Weight loss
Overview
Hydroxycitric acid (HCA), a derivative of citric acid, is found primarily in a small, sweet, purple fruit called the Malabar tamarind, or, as it is most commonly called, Garcinia cambogia. Test-tube and animal research suggest that HCA may be helpful in weight loss because of its effects on metabolism. However, studies in humans have found mixed results.
HCA may also have applications in developing new kidney medications for individuals prone to kidney stones. HCA has shown an ability to reduce the occurrence of kidney stones and dissolve existing stones.
Requirements and Sources
HCA is not an essential nutrient for the body. The Malabar tamarind is the only practical source of this supplement, particularly in the rind of its fruit. Other relatively negligible sources of HCA include the plant roselle (Hibiscussabdariffa), apples, berries, plums, cherries, peaches, citrus fruits, carrots, cabbages, eggplants, coffee, and artichokes.
Therapeutic Dosages
A typical dosage of HCA is 250 to 1,000 milligrams (mg) three times daily. Supplements are available in many forms, including tablets, capsules, powders, and even snack bars. Products are often labeled G. cambogia and standardized to contain a fixed percentage of HCA. Various proprietary forms of HCA are also available and are often claimed by their promoters to be more effective.
Therapeutic Uses
Although animal and test-tube studies, as well as a handful of human trials, suggest that HCA might encourage weight loss, other studies have found no benefit. Some positive therapeutic evidence exists for HCA in treating and preventing kidney stones. HCA binds to calcium oxalate crystals, preventing them from adhering to and damaging kidney walls. However, this finding requires further research.
Scientific Evidence
It remains unclear whether HCA offers any weight-loss benefits. In an eight-week double-blind, placebo-controlled trial of sixty overweight individuals, the use of HCA at a dose of 440 mg three times daily produced significant weight loss compared with placebo. In contrast, a twelve-week, double-blind, placebo-controlled trial of 135 individuals who were overweight who were given either a placebo or 500 mg of HCA (as G. cambogia extract standardized to contain 50 percent HCA) three times daily found no effect on body weight or fat mass. However, this study has been criticized for using a high-fiber diet, which is thought to impair HCA absorption.
A twelve-week double-blind trial of eighty-nine individuals found that HCA did not affect appetite, while other research indicated that HCA contributes to appetite reduction by increasing the body's fat oxidation rate. Another study tested HCA to see if it could cause weight loss by altering metabolism, but no effects on metabolism were found. Conversely, another study found that HCA improves metabolism by promoting ideal blood triglyceride (cholesterol) levels. Many in the complementary and alternative medicine community still tout HCA for its weight loss properties and ability to boost endurance. Others claim HCA can lower cholesterol, prevent diabetes, and stop cell damage. Some studies have found that patients with nonalcoholic fatty liver disease lose weight quickly when they incorporate an HCA supplement into their diet. Further clinical study in humans is necessary.
Safety Issues
The Malabar tamarind, from which HCA is extracted, is a traditional food and flavoring in Southeast Asia. No serious side effects have been reported from animal or human studies involving either fruit extracts or the concentrated chemical. A proprietary calcium-potassium salt of HCA appears to have undergone considerable formal safety study without evidence of toxicity appearing. However, maximum safe doses have not been established, especially for pregnant or nursing women, young children, or people with severe liver or kidney disease. Patients monitoring their blood sugar, those with Alzheimer’s disease, and those taking medications that may increase serotonin levels should not take HCA. Patients on any medication should consult with their healthcare provider as HCA has myriad drug interactions.
HCA has been involved in several supplement controversies in the twenty-first century. In 2009, the US Food and Drug Administration banned the sale of the weight loss supplement Hydroxycut, of which HCA was an ingredient. In 2012, television personality Dr. Mehmet Oz touted the ability of HCA to aid in weight loss without additional diet or exercise. In 2014, he was chastised in front of the US Senate for using his platform to promote unsubstantiated medical claims.
Bibliography
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