People who are decades away from retirement often aren’t too concerned about their calcium intake—but a new study suggests that they should be. A review and meta-analysis from Wenzhou Medical University found that among 35-year-olds, greater calcium intake improved bone mineral density and/or bone mineral content compared to a placebo or no treatment.

Bone mass gradually increases early in life before it peaks and reaches a plateau at age 20 to 35, then begins to decline. According to the study, having a “head start” on bone health while you’re still young might pay dividends when it really matters: old age, when bone density loss is inevitable.

“Our review provides a new train of thought regarding calcium [intake] and the optimal timing of its effects,” senior author Shuran Wang stated. “In terms of bone health and an individual’s full life cycle, the intervention window of calcium [intake] should be advanced to the age around the plateau of peak bone mass – namely at 20–35 years of age.”

The researchers determined that boosting the calcium intake of the diet with less than 1,000 milligrams calcium per day improved bone mineral density or bone mineral content. Increased calcium intake was more effective among people aged 20 to 35 years than in younger individuals. Bone mineral density particularly increased in the femoral neck, the site of the majority of hip fractures.

The meta-analysis included 43 randomized, controlled trials that evaluated the effects of calcium from various sources with or without vitamin D on bone mineral density or bone mineral content in the forearm, lumbar spine, hip, femoral neck and/or total body among a total of 7,382 participants. The average age of the participants in each study ranged from 2.7 to 23.7 years. Some of the studies assessed the effects of non-food calcium sources while the remainder evaluated the impact of food sources of the mineral. The findings appeared on September 27, 2022, in the journal Elife.¹