Calcium absorption is most efficient when taken in amounts of what per dose?

• A. 1200 mg
• B. 1000 mg
• C. 500 mg or less
• D. 800 mg with iron

Answer: (C)

Calcium absorption happens best when you take smaller portions at a time because the intestine can only transport a limited amount in one sitting. About 500 mg or less per dose is absorbed efficiently; when you exceed that, the absorption process becomes saturated and a smaller fraction is absorbed, with the rest passing through. To maximize total daily absorption, spread calcium intake into multiple doses rather than one large dose. (Note: the form and timing matter too—calcium carbonate is best with meals, while calcium citrate can be taken with or without food—but the key point for per‑dose efficiency is about 500 mg or less.)