Thymus Extract
A bovine glandular product based on the idea that thymus peptides can prime the immune system. The supporting trials are Italian paediatric studies from the 1980s and 1990s; nothing modern replaces them.
Evidence last reviewed: August 2026
What the science says
- Old paediatric trials of thymomodulin Limited evidence
A randomized trial in children with recurrent respiratory infections reported a preventive effect of thymomodulin, a calf thymus derivative. These studies are more than three decades old, small, single-country, and reported in ways that would not meet current standards.
- Modern reviews cover different products Limited evidence
A Cochrane review of immunostimulants for preventing exacerbations in chronic bronchitis and COPD found possible reductions in exacerbations but rated the evidence low quality, and the agents assessed are pharmaceutical bacterial lysates rather than over-the-counter bovine thymus supplements.
- Oral peptides face a basic obstacle Limited evidence
Thymic peptides are proteins, and swallowed proteins are digested. No trial has demonstrated that intact bioactive thymic peptides reach the circulation from an oral supplement.
Dosage & safety
Scientific references
Where to buy
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