EFSA Sets Safe Daily Limits for Clostridium Butyricum Use in Novel Foods as High as 3.2×10⁸ CFU

On May 2, 2025, the European Food Safety Authority (EFSA) released a scientific opinion on the safety of Clostridium butyricum TO-A, a probiotic proposed as a novel food ingredient in dietary supplements. This strain, commonly linked to gut health, has now undergone a comprehensive assessment by EFSA’s NDA panel, which covers nutrition, new foods, and food allergens.

EFSA confirmed that the production process, formulation, and stability of the product raise no immediate safety issues. A 90-day repeated oral toxicity study in rats was used as the foundation for estimating human safety thresholds, with a conservative uncertainty factor of 200 applied.

The panel emphasized microbiota development in early life as a critical factor for long-term health, and recommended excluding infants under 3 years old, as well as pregnant and breastfeeding women from the target user group.

According to EFSA’s assessment, the safe daily intake levels of C. butyricum TO-A were established as:

• 1.0 × 10⁸ CFU/day for children aged 3 to under 10

• 2.0 × 10⁸ CFU/day for adolescents aged 10 to under 14

• 2.8 × 10⁸ CFU/day for adolescents aged 14 to under 18

• 3.2 × 10⁸ CFU/day for adults

This decision paves the way for potential market approval of the strain as a regulated food supplement within the EU, pending final regulatory steps.