ADELAIDE, AUSTRALIA. The Recommended Daily Allowance (RDA) for calcium for men in the USA and Canada is 1000 mg/day up to the age of 50 years and 1200 mg/day for men above age 50. In view of recent reports that high calcium intakes may be detrimental, it is obviously important to know if the RDA reflects the actual amounts needed to achieve a steady calcium balance. A group of researches at the Royal Adelaide Hospital now report that the amount of calcium needed to maintain a steady calcium status is 750 mg/day for men below the age of 60 years. They acknowledge that men older than 60 may need more as the ability to absorb calcium declines with age.
The researchers obtained balances for 72 men aged 17 to 59 years and found that net absorbed calcium (the difference between intake and losses through faeces) was equal to the loss through skin (estimated at 40 mg/day) and urine at an average intake of 750 mg/day. In other words, 750 mg/day will maintain calcium status in men under the age of 60 years. It is common practice to add two standard deviations to the actual intake required to neither lose nor gain a nutrient, thus arriving at a RDA of 900 mg/day.
Nordin, BEC and Morris, HA. Recalculation of the calcium requirement of adult men. American Journal of Clinical Nutrition, Vol. 93, February 2011, pp. 442-45