Cistanche Deserticola: Is It Safe? Research Findings

Key Findings

This 90-day subchronic toxicity study found no evidence of systemic toxicity or adverse effects in Sprague-Dawley rats fed powdered Cistanche deserticola at doses up to 8% of their diet (equivalent to 7.8 g/kg body weight/day). The no-observed-adverse-effect level (NOAEL) was established at 7.8 g/kg/day, the highest dose tested. No mortality, changes in body/organ weights, food consumption, blood biochemistry, hematology, or histopathological abnormalities were reported across treatment groups.

Study Design

The study employed a subchronic oral toxicity design in 80 Sprague-Dawley rats (sex distribution unspecified, but likely equal males/females per standard toxicology protocols). Rats were divided into four groups (n=20/group) and fed diets containing 0% (control), 2%, 4%, or 8% powdered C. deserticola for 90 consecutive days. Toxicological assessments included mortality monitoring, body/organ weight measurements, food intake tracking, clinical chemistry, hematology, gross necropsy, and histopathological analysis of major organs.

Dosage & Administration

Powdered C. deserticola was administered via dietary incorporation at concentrations of 2%, 4%, and 8% (w/w). The highest dose (8%) corresponded to an estimated 7.8 g/kg body weight/day, based on reported food consumption data. The control group received an untreated diet. Dosing duration was 90 days, aligning with OECD guidelines for subchronic toxicity testing.

Results & Efficacy

The study did not assess efficacy, as its focus was safety. All measured parameters showed no statistically significant differences between treatment and control groups:
- Mortality: No deaths occurred.
- Body/organ weights: No dose-dependent changes in weight of liver, kidney, heart, spleen, or other organs.
- Hematology/biochemistry: No abnormalities in red/white blood cell counts, hemoglobin, liver/kidney function markers, or electrolyte levels.
- Histopathology: No treatment-related lesions in tissues examined.
The absence of adverse effects at the highest dose (7.8 g/kg/day) supports its short-term safety profile in rats.

Limitations

1. Species extrapolation: Results in rats may not fully predict human responses.
2. Short duration: 90 days is insufficient to assess long-term or chronic toxicity.
3. Lack of reproductive/developmental endpoints: Safety for pregnant individuals or during prolonged use remains untested.
4. Formulation specificity: The powdered form tested may differ in bioavailability from extracts or capsules commonly used in supplements.
5. Limited statistical detail: The summary does not specify p-values or confidence intervals for individual outcomes, though overall conclusions state no significant treatment effects.

Clinical Relevance

This study provides preclinical evidence that powdered C. deserticola is well-tolerated in rats at high doses (up to 7.8 g/kg/day), suggesting a wide safety margin for short-term use. For supplement users, this supports the potential safety of C. deserticola as a food ingredient, though human trials are needed to confirm these findings. The lack of observed toxicity aligns with its traditional use but does not address long-term risks or effects in sensitive populations (e.g., pregnant individuals, those with organ dysfunction). Doses in human supplements should consider allometric scaling from animal data, though specific recommendations require further research.

Conclusion: The study demonstrates the safety of powdered C. deserticola in a rodent model over 90 days, but clinical validation and longer-term studies are necessary to generalize these findings to humans.