Answer: Calcium Citrate (e.g. Citracal)
Explanation: Calcium Citrate has better absorption than calcium carbonate, in patients with higher gastric pH (i.e. low stomach acid)
Fun Fact: Absorption of calcium is greatest when taken in a dose of 500 mg elemental calcium or less
References: Trailokya, A., Srivastava, A., Bhole, M. and Zalte, N. (2017). Calcium and Calcium Salts. [online] Japi.org. Available at: http://www.japi.org/february_2017/24_dc_calcium_and_calcium_salts.pdf [Accessed 9 Feb. 2019].
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