The NIH Office of Dietary Supplements recommends 1,000mg of calcium per day for most adults, rising to 1,200mg for women over 50 and men over 70. Most people get less than the recommended amount, particularly those who avoid dairy.
Dairy
Dairy products are the most concentrated dietary calcium sources and the most efficient way to meet the daily target:
- Plain Greek yoghurt — ~250mg per cup
- Milk (any fat content) — ~300mg per cup
- Cheddar cheese — ~200mg per ounce
- Mozzarella — ~220mg per ounce
- Parmesan — ~330mg per ounce
- Cottage cheese — ~140mg per cup
Lactose-free dairy contains the same calcium as regular dairy, just with the lactose enzymatically broken down.
Leafy Greens and Vegetables
Several greens are surprisingly calcium-rich, though absorption varies — calcium from greens with high oxalate content (spinach, beet greens, Swiss chard) is less bioavailable than calcium from low-oxalate greens like kale and bok choy:
- Kale (cooked) — ~95mg per cup
- Collard greens (cooked) — ~270mg per cup
- Bok choy (cooked) — ~160mg per cup
- Turnip greens (cooked) — ~200mg per cup
- Broccoli (cooked) — ~62mg per cup
- Okra (cooked) — ~125mg per cup
Fish with Edible Bones
Some fish are calcium powerhouses because they are eaten with their soft bones:
- Sardines (canned with bones) — ~325mg per 3.75oz tin
- Canned salmon (with bones) — ~180mg per 3oz serving
- Anchovies (canned) — ~125mg per 2oz tin
Fortified Plant Milks and Tofu
For those who avoid dairy, fortified plant milks are calcium-equivalent to cow’s milk when properly enriched:
- Fortified almond milk — ~450mg per cup (varies by brand)
- Fortified soy milk — ~300mg per cup
- Fortified oat milk — ~350mg per cup
- Tofu (calcium-set) — ~250–400mg per half cup
Check the label — not all plant milks are fortified, and amounts vary substantially between brands.
Other Sources
- Almonds — 75mg per ounce
- Chia seeds — ~180mg per ounce
- White beans — ~160mg per cup cooked
- Figs (dried) — ~120mg per ½ cup
- Fortified orange juice — ~350mg per cup
- Fortified breakfast cereals — varies (check label)
Vitamin D Matters Too
Calcium absorption depends on adequate vitamin D — without it, you absorb only a fraction of what you consume. Most people need both adequate calcium intake and adequate vitamin D status for bone health. See our companion post on vitamin D foods for more on this.
Should You Supplement?
For most people who eat dairy or fortified alternatives, food sources alone provide enough calcium. Calcium supplements have been associated with increased risk of kidney stones and some cardiovascular concerns in observational studies, so food sources are generally preferred. If you cannot reach your target through food (this is common for postmenopausal women and people who avoid dairy entirely), discuss supplementation with your doctor rather than self-prescribing high-dose calcium pills.
References
- NIH Office of Dietary Supplements — Calcium — Authoritative reference on calcium
- NIH — Calcium and Vitamin D: Important at Every Age — Federal guidance on calcium for bone health
- Harvard T.H. Chan — Calcium — Evidence-based overview
- Mayo Clinic — Calcium and calcium supplements — Clinical guidance on calcium and supplementation
- Dietary Guidelines for Americans 2020-2025 — Federal calcium intake recommendations
- USDA FoodData Central — Reference database for nutrient content of foods