Low-Dose Psilocybin Shows Promise Against Obesity, Fatty Liver Disease, and Type 2 Diabetes in University of Padova Study

Low-Dose Psilocybin Shows Promise Against Obesity, Fatty Liver Disease, and Type 2 Diabetes in University of Padova Study

Psilocybin—the primary psychoactive compound in “magic mushrooms”—has drawn intense scientific interest mainly for its potential in treating depression, anxiety, and addiction through profound changes in consciousness and brain plasticity. A new preclinical study from the University of Padova (Padua), Italy, points to a completely different therapeutic angle: very low, non-psychedelic doses may improve key metabolic conditions, including obesity, metabolic dysfunction-associated steatotic liver disease (MASLD, formerly NAFLD), and type 2 diabetes.

Published in Pharmacological Research (2026; volume 224, article 108080; online first December 29, 2025), the work was led by Martina Colognesi and colleagues in the Department of Pharmaceutical and Pharmacological Sciences.

Study Design

Researchers used a well-established mouse model of diet-induced metabolic disease. Mice were fed a high-fat, high-fructose diet that reliably produces obesity, insulin resistance, hyperglycemia, and liver fat accumulation (steatosis). One group received chronic low-dose psilocybin at 0.05 mg/kg for 12 weeks; controls did not. This dose is far below levels that produce psychedelic or central nervous system effects.

The team assessed body weight, liver histology, insulin sensitivity, blood glucose, skeletal muscle function, and performed transcriptomic and lipidomic analyses of liver and muscle tissue. Follow-up experiments in human liver cell lines (using pharmacological blockers and CRISPR/Cas9 gene editing) probed the roles of serotonin receptors 5-HT2A, 5-HT2B, and 5-HT2C.

Key Findings

Treated mice showed several clear benefits despite continued exposure to the unhealthy diet:

• Reduced body-weight gain (without changes in food intake, pointing to a direct metabolic effect rather than simple appetite suppression).
• Decreased liver steatosis (fat accumulation).
• Improved insulin sensitivity and lower blood glucose (reduced hyperglycemia and insulin resistance).
• Better skeletal muscle strength and function, possibly linked to restored leptin sensitivity.

Multi-omics data indicated near-complete normalization of disrupted hepatic pathways involved in lipid and carbohydrate metabolism. Importantly, no central nervous system or psychedelic-like effects were observed at this dose.

Unexpected Mechanism

Classic psychedelic effects of psilocybin (via its active metabolite psilocin) are driven primarily by agonism at the 5-HT2A receptor in the brain. The metabolic benefits here proved independent of 5-HT2A. Instead, they depended on antagonism of the 5-HT2B receptor in the liver. CRISPR knockout and pharmacological experiments confirmed that blocking or removing 5-HT2A did not abolish the metabolic improvements, while 5-HT2B activity was central.

This peripheral, non-psychedelic mechanism is a notable shift from most prior psilocybin research.

Implications and Caveats

If these results translate to humans, low-dose (or non-psychedelic analog) psilocybin could offer a novel, orally available approach to the interconnected cluster of obesity, MASLD, type 2 diabetes, and related muscle decline (sarcopenia)—conditions that currently place enormous burdens on global health systems. The absence of psychoactive effects at the tested dose could simplify clinical development and broaden potential patient populations.

However, this remains a preclinical study in mice and cell lines. Human trials are essential to confirm safety, efficacy, optimal dosing, and long-term outcomes. Some authors have disclosed relationships with companies interested in psilocybin-related intellectual property, which is common in the field but worth noting.

Related work from the same group has also explored psilocybin’s hepatoprotective potential in models of steatohepatitis, reinforcing interest in its effects on liver metabolism and inflammation.

Looking Ahead

The University of Padova findings expand the scientific conversation around psilocybin beyond psychiatry into metabolic medicine. They highlight how a compound long associated with altered states of consciousness may also act as a subtle modulator of peripheral serotonin signaling with tangible metabolic benefits. As research continues, the distinction between psychedelic and non-psychedelic applications of tryptamine compounds is likely to become increasingly important for both science and potential therapeutics.

Source: Colognesi M, et al. Low, non-psychedelic doses of psilocybin as a novel treatment for MASLD, obesity and type 2 diabetes via 5-HT2B receptor-dependent mechanisms. Pharmacological Research. 2026;224:108080. DOI: 10.1016/j.phrs.2025.108080.