Calcium is the most abundant mineral in your body; almost all of it is stored in bones and teeth, and the rest helps muscles move and nerves send messages2.
Almost all body calcium is stored in bones and teeth, giving them structure and hardness2.
Your muscles need calcium to move2.
Nerves need calcium to carry messages between your brain and every part of your body2.
Helps blood vessels contract and relax to move blood around your body1.
The small pool of calcium in blood and tissues takes part in blood clotting1.
| Food and serving | Amount |
|---|---|
| Yogurt, plain, low fat, 8 oz | 415 mg |
| Mozzarella, part skim, 1.5 oz | 333 mg |
| Milk, nonfat, 1 cup | 299 mg |
| Soymilk, calcium fortified, 1 cup | 299 mg |
| Tofu, firm, made with calcium sulfate, ½ cup | 253 mg |
| Soybeans, cooked, ½ cup | 131 mg |
| Kale, cooked, 1 cup | 94 mg |
| Chia seeds, 1 tablespoon | 76 mg |
| Food and serving | Amount |
|---|---|
| Sardines, canned in oil, with bones, 3 oz | 325 mg |
| Salmon, pink, canned, with bones, 3 oz | 181 mg |
About 30% of calcium from dairy and fortified foods is absorbed, but oxalates cut absorption from spinach to about 5%1. Amounts per serving from1.
Many fruit juices, soy and almond drinks, tofu and ready-to-eat cereals have added calcium; check the label1.
The same reference table draws the reference lines on your charts in Ayuvo. Needs differ in pregnancy and breastfeeding, which are not covered here.
| Age | Women | Men | Upper limit |
|---|---|---|---|
| 19–30 | 1,000 mg | 1,000 mg | 2,500 mg |
| 31–50 | 1,000 mg | 1,000 mg | 2,500 mg |
| 51–70 | 1,200 mg | 1,000 mg | 2,000 mg |
| 71+ | 1,200 mg | 1,200 mg | 2,000 mg |
RDA (Recommended Dietary Allowance) is the daily amount that meets the needs of nearly all healthy people. Per day, for adults1.
Upper limit (UL) is the most per day that is unlikely to cause harm. Applies to food, drinks and supplements combined.
Signs like these have many possible causes. They are a reason to talk to a clinician, not to self-treat.
Getting too little calcium over time can lead to weak, fragile bones2.
Higher supplemental intakes might raise kidney stone risk, while very high blood calcium usually comes from a health condition, not diet1.
Blood calcium is tightly controlled, so it doesn't reflect how much you eat; a bone density scan better reflects long-term calcium status1.
| Serum calcium | What it may mean |
|---|---|
| < 8.5 mg/dL | Low (hypocalcemia) |
| 8.8–10.4 mg/dL | Typical range in healthy people |
| > 10.5 mg/dL | High (hypercalcemia) |
Labs use different units and ranges. Your clinician reads a result alongside your history and other tests.
The two most common forms are calcium carbonate and calcium citrate, and the label lists elemental calcium1.
About 40% calcium by weight; absorbed more fully when taken with food1.
About 21% calcium; less dependent on stomach acid, so it can be taken without food1.
Gluconate, lactate, phosphate and other forms appear in supplements and fortified foods2.
Supplements can interact with medicines. Talk to a clinician or pharmacist before you start one, especially at high doses.
Yes, several non-dairy foods help. Calcium-set tofu, fortified soy and almond drinks, fortified juices and cereals, kale, bok choy, and canned sardines or salmon with bones all provide calcium. Check labels, because tofu made without a calcium salt has little calcium.
Calcium carbonate contains more calcium by weight and is absorbed more fully with food. Calcium citrate is absorbed well with or without food and is easier to absorb for people with low stomach acid, which is more common in older adults.
Spinach contains oxalic acid, which binds calcium into a form your gut can't absorb well. Greens without much oxalate, such as kale, broccoli and bok choy, give up their calcium about as well as milk does, though they contain less per serving.
Ayuvo charts calcium by day, week, month and year, with the reference lines from this page, personalised by age and sex where they differ. Supplements you log in Medications count too. Free, with no account.
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Facts on this page come from these sources, checked on the dates shown. Intake numbers come from Ayuvo's shared reference table, which cites the sources marked for them.
General information, not medical advice. This guide is for healthy adults and does not cover pregnancy, breastfeeding, children or medical conditions. It cannot diagnose or treat anything. Talk to a clinician before starting high-dose supplements, or if you think you may have too little or too much of a nutrient. Spotted an error? Email us.