Garcinia Cambogia (HCA) Supplements: Are They Safe?

Key Findings

This review concludes significant safety uncertainties exist for hydroxycitric acid (HCA) from Garcinia cambogia in sports supplements. Subchronic animal studies identified testicular toxicity (testicular atrophy and impaired spermatogenesis) at high doses, establishing a no observed adverse effect level (NOAEL) of 389 mg HCA/kg body weight/day. Crucially, the review states there is a "lack of adequate human data on the safety of HCA preparations, particularly with respect to the human male reproductive system," leading to substantial safety concerns for supplements containing high HCA amounts. Unlike synephrine (the other compound reviewed), no safe human intake level for HCA could be established due to insufficient evidence.

Study Design

This is a narrative review (not a primary research study) published in 2017. It synthesizes and evaluates existing scientific literature, including animal studies, human studies, and case reports, specifically focusing on risk assessment for synephrine and HCA in sports supplements. The review methodology involved analyzing data from previously published research to identify potential health risks and establish safety thresholds where possible. No original data collection, human/animal subjects, or experimental intervention was conducted by the authors.

Dosage & Administration

The review analyzed doses reported in prior studies. For HCA, the critical finding came from subchronic animal studies where high doses of "certain HCA-containing preparations" were administered. The established NOAEL was 389 mg HCA/kg body weight/day in animal models. The review does not specify exact human doses used in the cited human studies for HCA, emphasizing the lack of robust human safety data instead. Administration routes in the underlying animal studies were typically oral.

Results & Efficacy

The review focused solely on safety, not efficacy. It found no evidence supporting the safety of high-dose HCA supplements in humans. The primary safety result was the identification of testicular toxicity in animal models at doses exceeding the NOAEL of 389 mg HCA/kg bw/day. The review explicitly states that due to the absence of adequate human safety data, particularly concerning male reproductive health, "substantial uncertainties exist regarding the safety" of high-HCA supplements. No statistical analyses (p-values, confidence intervals) of efficacy or safety outcomes were performed within this review itself.

Limitations

As a review, its limitations stem from the quality and availability of the underlying primary research. Key limitations highlighted include: the "lack of adequate human data on the safety of HCA preparations," especially long-term human studies on reproductive health; reliance on animal data which may not perfectly translate to humans; potential variability in HCA preparation composition across studies; and the absence of dose-response data in humans to establish a safe intake level. The review inherently cannot resolve these data gaps.

Clinical Relevance

Supplement users, particularly athletes and men, should be aware of significant safety uncertainties regarding high-dose Garcinia cambogia (HCA) supplements. The animal evidence of testicular toxicity, coupled with the lack of conclusive human safety data, suggests potential risks to male reproductive health that are not adequately characterized. Consumers should exercise caution with HCA-containing products, especially those providing high doses, and recognize that the common perception of "natural = safe" does not apply. Healthcare providers should counsel patients on these unresolved safety concerns. Further human studies are critically needed.