Micronutrients
Calcium and bone health: how much you need
Bone isn't inert scaffolding — it's living tissue that's constantly broken down and rebuilt, and calcium is the raw material for the rebuilding half.
How much you need
| Group | RDA |
|---|---|
| Adults 19–50 | 1,000 mg/day |
| Women 51–70 | 1,200 mg/day |
| Adults 71+ | 1,200 mg/day |
Requirements rise later in life because absorption efficiency falls and, after menopause, bone loss accelerates.[1]
Where to get it
Dairy is the most concentrated common source, but it's far from the only one: canned sardines and salmon (with the bones), tofu set with calcium salts, fortified plant milks, kale, bok choy, and broccoli all contribute meaningfully. Spinach contains calcium but binds much of it in oxalates, making it poorly absorbed — a good example of why the number on a label isn't the whole story.[1]
Calcium doesn't work alone
Absorbing calcium depends on adequate vitamin D, and the signal that tells your body to deposit calcium into bone is mechanical loading — resistance training and weight-bearing activity. Calcium intake alone, without those two, is the least effective version of a bone-health strategy.[2]
Keep reading: Vitamin D explained · Micronutrients vs. macronutrients · Protein intake for women