Goji berries, from the plant *Lycium barbarum*, have been consumed for millennia in traditional Chinese medicine for their tonic properties, particularly regarding sexual vitality and fertility. They are often presented as a “natural testosterone booster.” This article examines the available scientific evidence on the link between goji berries (or their extracts) and testosterone levels, distinguishing between preclinical (animal) studies and clinical data in humans. We rely exclusively on published studies to avoid misinformation. Important note: Contrary to some popular claims that goji berries directly and significantly increase testosterone in humans with regular consumption, robust scientific evidence is lacking in humans. The observed effects are primarily protective or restorative in models of stress or deficiency, and are mostly derived from animal studies. There is no conclusive evidence of a “boosting” effect in healthy individuals.
What is *Lycium barbarum*? Lycium barbarum, commonly known as goji berry or wolfberry, is a shrub native to Asia whose dried red fruits are rich in polysaccharides (LBP), flavonoids, carotenoids (such as zeaxanthin), and other antioxidant compounds. In Traditional Chinese Medicine, these berries are used to tonify Qi, nourish the blood, protect the liver and kidneys, and improve reproductive function.
The main active compounds involved in the potential effects on reproductive health are the polysaccharides of Lycium barbarum (LBP), which possess antioxidant, anti-inflammatory, and immunomodulatory properties.
Effects on testosterone: what animal studies say Most research demonstrating a positive link with testosterone comes from studies on animal models, often in contexts of oxidative stress, late-onset hypogonadism, or toxicity:In aged rats modeling late-onset hypogonadism (LOH), goji extracts (Lycium chinense, a closely related species) increased serum testosterone levels, improved sperm count and motility, and reduced testicular oxidative stress.
LBPs protected the testes against toxins such as doxorubicin and radiation, restoring testosterone levels and mitigating oxidative damage. In mouse and rat models of diabetes and obesity, LBPs improved testicular function, increased testosterone, and reduced inflammation. A glycopeptide isolated from Lycium barbarum promoted testosterone synthesis in Leydig cells in vitro and in vivo, via the regulation of pathways such as TGF-β.
These studies suggest that goji compounds exert a protective effect on testosterone production by reducing oxidative stress and cell apoptosis, rather than a direct stimulatory effect in healthy subjects.
Human evidence: limited and indirect
- Randomized clinical trials in humans are rare and do not demonstrate a direct increase in testosterone:No study has shown a significant increase in testosterone levels in healthy men consuming goji berries or standardized juice.
- A recent trial on patients with varicocele (a scrotal venous problem linked to infertility) tested an extract of LBP: although improvements in oxidative stress and sperm parameters were observed, testosterone levels were not significantly altered (measured but not noticeably increased).
- Studies on general well-being (goji juice) have reported a subjective improvement in vitality, but without specific hormonal measurements.
- Claims of an aphrodisiac effect or increased libido often rely on tradition and indirect effects (improved energy, reduced stress), rather than a measurable increase in testosterone. Potential Mechanisms
The effects observed in animal models involve:
Reduction of oxidative stress (increased SOD, reduced malondialdehyde).
Protection of Leydig cells (testosterone-producing cells).
- Modulation of pathways such as PI3K/Akt or TGF-β to promote steroidogenesis.
- These mechanisms could be beneficial in cases of deficiency related to age, stress, or disease, but not necessarily in healthy individuals.
- Precautions and Consumption
Goji berries are generally safe for dietary consumption (20-30 g/day). They can interact with anticoagulants (warfarin) or blood pressure medications. Consult a doctor if you are currently taking these medications, are pregnant, or have an allergy.
For potential effects on reproductive health, studies often use concentrated LBP extracts, which are not equivalent to regular consumption of dried berries.
- Conclusion
- ) possess demonstrated antioxidant and protective properties, particularly in animal models of testosterone deficiency. They may help preserve reproductive function in cases of oxidative stress or aging. However, there is no strong scientific evidence demonstrating that they naturally increase testosterone in healthy humans. Marketing claims of a “natural testosterone booster” are exaggerated and not supported by robust clinical trials. A diet rich in antioxidants remains beneficial, but for hormonal issues, consult a healthcare professional.
Scientific References
Park HJ, et al. “Lycium chinense Mill improves hypogonadism via anti-oxidative stress and anti-apoptotic effect in old aged rat model.”
Aging Male
, 2019. DOI: 10.1080/13685538.2018.1498079
Liang J, et al. “Lycium barbarum Glycopeptide Promotes Testosterone Synthesis and Glucose Metabolism in Leydig Cells of the Testis.”Biomolecules, 2025. DOI: 10.3390/biom15030425
Zhou L, et al. “Protective effect of Lycium barbarum polysaccharides against doxorubicin-induced testicular toxicity in rats.”
- Andrologia , 2012.Shi GJ, et al. “The effects of Lycium barbarum polysaccharide on oxidative stress and sperm health in varicocele patients: A randomized clinical trial.”
- Andrologia , 2025 (preprint).Lau BWK, et al. “Administration of Goji (Lycium chinense Mill.) Extracts Improves Erectile Function in Old Aged Rat Model.”
- World J Mens Health , 2017.Teixeira F, et al. “Lycium barbarum Berries (Solanaceae) as Source of Bioactive Compounds for Healthy Purposes: A Review.”
- Int J Mol Sci , 2023. DOI: 10.3390/ijms24054777
