Calcium is the nutrient crucial for building and maintaining strong bones and teeth.
This mineral combines with phosphate to form calcium-phosphate crystals, especially hydroxyapatite, which give bones and teeth much of their hardness and strength. More than 99% of the body’s calcium is stored in these tissues. Calcium also supports muscle contraction, nerve signaling, blood clotting, and a normal heartbeat.
The body cannot manufacture calcium, so it must come from food or supplements when necessary. Dairy products such as milk, yogurt, and cheese are familiar sources; fortified plant milks, canned fish with edible bones, tofu made with calcium, and some leafy greens can also contribute.
Vitamin D is a common source of confusion. It does not replace calcium, but it helps the intestines absorb calcium. If dietary calcium remains too low, the body can draw calcium from bones, potentially weakening them over time. Adequate calcium, vitamin D, weight-bearing activity, and overall nutrition all contribute to bone health.