Androgenic Alopecia and the Gut Microbiome
Androgenetic Alopecia is typically framed as a hormone issue, specifically, the follicle’s sensitivity to dihydrotestosterone (DHT), a potent androgen derived from testosterone. But there’s a deeper, systemic story that’s often overlooked: the role of inflammation and the gut microbiome in hormone regulation.
When gut bacteria are imbalanced, the liver’s ability to detoxify and clear excess hormones is compromised. Certain gut microbes help break down and metabolise circulating estrogens and androgens, while others (when overgrown) can produce beta-glucuronidase, an enzyme that reactivates hormones previously marked for excretion—sending them back into circulation.
This recycling of hormones, coupled with gut-derived inflammation, sets up a perfect storm:
- Higher active DHT levels systemically
- Increased sensitivity at the follicle
- Depleted antioxidants like vitamin E and glutathione (needed to protect hair follicle cells)
- Immune hyperreactivity that accelerates microinflammation around the follicle
This means that effective treatment for androgenetic alopecia should go beyond blocking DHT and address the health of the gut–liver axis. Dietary and lifestyle changes can significantly influence this system. Reducing added sugars and ultra-processed foods helps lower chronic inflammation and prevents the overgrowth of harmful gut bacteria.
Increasing fibre intake, especially from vegetables, legumes, and prebiotic foods like leeks, chicory, and oats—feeds beneficial microbes and promotes short-chain fatty acid production, which supports hormone clearance and reduces systemic inflammation.
Zinc supplementation has been shown to improve the composition of the gut microbiome by increasing populations of beneficial bacteria, while also supporting tight junctions in the gut lining and regulating androgen metabolism.
Regular exercise further enhances gut motility, ensuring efficient elimination of hormone metabolites and inflammatory byproducts. Together, these changes help calm the internal environment, reduce inflammatory signals to the scalp, and create the metabolic conditions hair follicles need to remain resilient.
Even in individuals with “normal” hormone levels, a poor microbial population can tip the balance. Harmful gut bacteria—particularly those that produce beta-glucuronidase—can re-release hormones like DHT back into circulation after the body has already marked them for elimination.
In contrast, a healthy and diverse microbial ecosystem supports hormone breakdown and safe excretion. This means that a poor diet doesn’t just affect digestion—it can directly elevate androgen levels systemically, even without overt endocrine disorders. In androgenetic alopecia, this internal imbalance quietly amplifies follicular stress and accelerates miniaturisation.
