Abstract
Calcium montmorillonite (CMM) clay is a naturally occurring mineral with a longstanding history in medical applications, now receiving increased scientific attention for its broad therapeutic potential. Known for its ability to bind a range of harmful substances, including bacterial toxins, heavy metals, mycotoxins, and inflammatory mediators, it exerts its effects without systemic absorption, acting locally within the gastrointestinal tract or at the skin surface. This narrative review synthesizes current clinical and preclinical evidence on the human health applications of calcium montmorillonite, with focused sections on the gastrointestinal/metabolic, dermatologic, immune, and musculoskeletal systems. The gastrointestinal section covers its documented role in treating pediatric diarrhea, radiation enteritis, and dietary toxin exposure. In dermatology, the clay has been incorporated into topical preparations for acne, rashes, and wound care, supported by both laboratory data and real-world use. Hepatic and metabolic studies suggest that it may reduce liver fat accumulation, improve glucose metabolism, and modulate the gut microbiome, particularly in models of non-alcoholic fatty liver disease and obesity. Additional sections explore its potential relevance in renal toxin clearance, immune regulation, mucosal healing, and surgical recovery. Across these systems, calcium montmorillonite has demonstrated a strong safety profile, with minimal nutrient interaction and no evidence of systemic toxicity when properly sourced and used in appropriate contexts. With growing access to carefully studied, pharmaceutical-grade formulations, CMM may offer safe and consistent benefits across clinical and preventive care settings.