Shankh Bhasma (Conch Shell Ash)

Shankh Bhasma is not a food or dietary supplement in the conventional sense but a calcined mineral preparation. Its primary composition is calcium carbonate (CaCO3), which upon traditional incineration (shodhana and marana processes) converts largely to calcium oxide (CaO) and trace mineral oxides. Key constituents and approximate concentrations: **Primary mineral:** Calcium (Ca) — approximately 35–39% by weight (predominantly as calcium oxide/calcium carbonate forms); serves as a highly bioavailable source of elemental calcium due to the repeated calcination process reducing particle size to the nanoscale (often <100 nm), which significantly enhances intestinal absorption compared to raw calcium carbonate (bioavailability estimated 1.5–2× higher than unprocessed shell). **Trace minerals:** Iron (Fe) — 0.02–0.1%; Magnesium (Mg) — 0.1–0.5%; Zinc (Zn) — trace amounts (~0.01–0.05%); Strontium (Sr) — trace; Sodium (Na) — trace; Phosphorus (P) — trace amounts. **Bioactive compounds:** The alkaline nature (pH ~9–12 in aqueous suspension) is itself pharmacologically active, acting as a natural antacid. No significant protein, fat, fiber, carbohydrate, or vitamin content. **Other characteristics:** Contains no organic macronutrients; caloric value is negligible (essentially zero). The bhasma form may contain trace amounts of carbon residue from organic media (e.g., Aloe vera juice, lemon juice) used during the levigation (bhavana) process, potentially contributing minor organic acids and phytochemicals at sub-therapeutic levels. **Bioavailability notes:** The traditional multi-cycle calcination and trituration process yields ultra-fine particles (nanoparticle range), dramatically increasing the surface-area-to-volume ratio. This enhances dissolution in gastric acid and subsequent calcium ion absorption in the duodenum. Studies on properly prepared bhasmas suggest particle sizes of 30–90 nm, which facilitates transcellular and paracellular absorption pathways. Heavy metal contamination (lead, mercury, arsenic) must be absent or within permissible limits per Ayurvedic Pharmacopoeia standards (Pb <10 ppm, Hg <1 ppm, As <3 ppm). Typical therapeutic dose: 125–500 mg, taken 1–2 times daily with honey, ghee, or warm water as anupana (vehicle), which further modulates bioavailability.