Bone health requires calcium, but adequate calcium intake alone is insufficient for bone maintenance. Vitamin D, vitamin K2, magnesium, protein, acid-base balance, and mechanical loading all contribute to bone mineral density. A plant-based diet that includes calcium-rich plant foods, adequate vitamin D supplementation, fermented soy and aged hard cheese for K2, and sufficient protein from legumes can support bone health as well as or better than a dairy-inclusive diet.
Calcium from Plant Sources
- Cooked kale, bok choy, and broccoli: provide highly bioavailable calcium at absorption rates of 40 to 64 percent, higher than the 32 percent absorption from cow's milk
- Calcium-set tofu: 350 to 500mg calcium per 100g portion; highly bioavailable
- Fortified plant milks: typically fortified to the same calcium level as cow's milk; bioavailability varies by fortification form
- White beans and edamame: significant calcium alongside protein, fibre, and magnesium
- Almonds: 75mg per 30g serving, with magnesium and vitamin E alongside the calcium
Vitamin K2 on a Plant-Based Diet
Vitamin K2 from natto (fermented soybeans) is the richest single plant source by a very large margin. Natto provides several times the K2 of any other food. Including natto regularly on a predominantly plant-based diet, or including aged hard cheese if dairy is not excluded, provides adequate K2 for bone health support.