Calcium intake in the primary prevention of osteoporosis has received much attention. Recommendations for the intakes of calcium and several bone-related nutrients were made in 1998 by the Institute of Medicine (Food and Nutrition Board, 1998).

Calcium intakes often do not meet the desired AI for age, especially for females. According to Arthritis Osteoporosis Dietitian in mumbai India near me Geetanjali Mengi , teen and adult women consume considerably less than the current AIs; men are more likely to consume somewhat greater amounts than women, but they do not meet the recommended levels either. These deficits translate, on average, into the need for an additional 500 mg/day for teenage girls and adult women. Although it is recommended that calcium should be supplied by foods because of the concurrent ingestion of other essential nutrients, many individuals, especially elderly women, may need to increase their intakes of calcium by using supplements.

A major concern among nutritionists is that a large percentage of girls beyond age 11 are not consuming sufficient amounts of calcium intake. The importance to adolescents of an adequate calcium intake is unquestioned, even though the precise requirements may not be known with certainty.

AI levels of calcium should be the first goal. In one study, the goal of increasing daily calcium intake from 80% of the RDA to 110% through supplementation with calcium citrate malate resulted in significant increases in spinal and total body bone density in adolescent girls, which may translate into later protection against osteoporosis (Lloyd et al., 1993).

Calcium consumption during childhood and adolescence is beneficial for the acquisition of peak bone mass (PBM). An 18-month double-blind study was conducted on BMD of 70 pairs of identical twins to determine the impact of additional calcium from supplements (Johnston et al., 1992). The twins who were given calcium supplements had significantly greater BMD at all sites after 18 months than those given placebo. Mean daily calcium intakes were 908 mg for those taking placebo, and 1612 mg for those taking the supplement. The gain in BMD from the supplement group, however, did not persist after an additional period of 12 months without supplementation.

Low calcium bioavailability from selected foods may adversely affect calcium status. For example, spinach and a few other high oxalate-containing vegetables have low calcium bioavailability (Weaver et al., 1991). Dairy products have high amounts of calcium in a well-absorbed form. Wheat bread may be a good source of calcium for those who consume a lot of bread; green, leafy vegetables such as broccoli, kale, and bok choy have good calcium bioavailability, and calcium from soybeans is also very well absorbed. The amount of calcium in major food sources is listed in Table 28–3.

An additional benefit of meeting calcium requirements from foods alone is that the foods containing calcium are also rich in several other nutrients needed for health in general, and for bone health in particular, and that the consumption of a calcium-rich diet from foods is also a marker of a balanced intake of all micronutrients.

Calcium is currently being added to some brands of orange juice at about 300 mg/cup of juice and some brands of soy milk at 200 to 300 mg/cup. It is also added to some breads and other foods.

Although increasing calcium intake for the first several years after menopause has little effect in slowing the high rate of BMD loss of 1% to 2% per year, it remains important to maintain an adequate calcium intake for even a potentially small benefit (Dawson-Hughes et al., 1990). Beyond these early postmenopausal years, however, BMD has been shown to be retained when calcium supplements are taken (Reid et al., 1993). One major benefit of the additional calcium from supplements is the suppression of PTH secretion and, hence, the retention of bone (McKane et al., 1996). Men are thought to respond to adequate intakes of calcium in a similar way as women. Recommendations to meet the current AIs seem reasonable at all ages, including the elderly years, to try to match calcium losses as best as possible and to suppress PTH.