Calcium Sources and Functions

Healthy Eating Minerals - Calcium

Calcium Sources

Healthy Eating Minerals - Calcium

All of the nutrient minerals work together to keep you healthy and feeling good. Here is a summary of the role of calcium, a major mineral in your good health.

What it does Helps maintain healthy bones and teeth, normal blood pressure and clotting and proper muscle and nerve function
Daily needs
[Infants: 200-260 mg] [Children: 700-1300 mg] [Men: 1,000-1300 mg] [Women: 1,000-1300 mg] [Pregnant: 1,000-1,300 mg] [Lactating: 1,000-1,300 mg]
Not enough Stunted growth in children; Osteoporosis in adults
Too Much Frequent urination; constipation; nausea; thirst; abdominal pain Severe: delirium; coma
Foods Dairy products; greens (kale family); legumes; some tofu

*The lower value is for infants up to 6 mos., the higher value is for infants up to a year old.
† The first value is for children 1-3 with the amount increasing until age 18.
# Adequate Intake (AI) is the average amount a healthy person consumes; no RDA established.

The most abundant mineral

Not surprisingly, calcium is the most abundant mineral found in your body, with most of it being located in your bones and teeth. The calcium in your bones allows you to have a rigid frame; without it, your bones would be soft, and you would have a posture like a wet noodle!

Calcium storage

In addition to providing a rigid structure for your muscles and tendons to attach to, the bones are also depositories for calcium, so that it is readily available to maintain your blood calcium levels. Although calcium is also stored in your teeth, it is less available than the calcium in your bones.

Interesting Fact: Although bones appear to be solid and unchanging, they are actually constantly gaining and losing minerals, including calcium. If your body detects that your blood calcium level is low, it can remove calcium from your bones to bring up the level in your blood. Conversely, when your blood calcium levels are high enough, your body can replace the calcium in your bones.

Important functions besides bone health

The calcium that circulates in your body is important for (1) normal blood pressure and  (2) clotting of the blood. It also is involved in the (3) contraction of your muscles, (4) blood vessel dilation, (5) hormone secretion, (6) enzyme activity and (7) normal nerve function. There is also some evidence that calcium may have a role in (8) maintaining a normal body weight and in the (9) prevention of diseases such as hypertension (high blood pressure), colon cancer, and diabetes.

Good sources of calcium

Calcium is found most abundantly in dairy products.

Milk… Yogurt… Cheese… Ice cream…

It is also found in some non-dairy sources.

Broccoli… Chia seed... Cauliflower… Kale… Parsley… Bok Choy… Tofu… Sardines and other fish eaten with their bones… Oysters… Almonds… Sesame seeds… White beans… Pinto beans… Sweet potatoes… Whole wheat bread…

--Caveat: Although calcium is present in some foods, such as spinach and rhubarb, these foods also contain oxalic acid, which binds the calcium and makes it virtually unavailable to your body. However, you can still enjoy these foods for all of the other important nutrients they contain, and you may get a small amount of absorbable calcium into the bargain!

Fortified products

Some products, such as orange juice, some fruit drinks, and some cereals, are fortified with calcium. It is important to note that the type of calcium used in fortification will affect its availability for absorption in your body. This means that it is possible that not all of the calcium listed on the label of the fortified food, will actually be accessible to your body.

Should I supplement with calcium pills?

As always, it is better to get your calcium from the foods you eat, especially because calcium works in concert with other vitamins and minerals. However, if you are unable to get enough calcium in your diet, possibly due to lactose-intolerance or a vegan lifestyle, you can supplement your diet with calcium pills. Talk to your health care provider about whether you should take a supplement and how much you need.

Be aware that most calcium supplements should be taken with meals and that for the sake of good absorption; you should limit your supplementation to 500 mg at one time. Accordingly, you may want to break up your calcium supplementation, taking one in the morning and one in the evening.


Not surprisingly, when calcium is discussed, the subject of osteoporosis often comes up. Since bone loss and calcium deficiency are closely linked, it is important to get enough calcium in your diet, especially in the first three decades of your life, when your bone density is being established.

Caveat: It is not easy to know if you are at risk for osteoporosis, since your blood calcium levels will not reflect bone loss. You can lose calcium from your bones for years, and it will not show up until the bone loss is in an advanced stage.

Who gets osteoporosis?

Risk factors associated with osteoporosis are well documented:

-Long-term calcium  and Vitamin D deficiency

-Women more than men

-Older people rather than younger

-Frail people rather than sturdy

-Cigarette smokers

-Excessive alcohol consumption

-Family history of osteoporosis

-Sedentary lifestyle

-Estrogen deficiency in women

-Testosterone deficiency in men

Although your chance of developing osteoporosis is affected by some factors you cannot control, such as heredity, gender and age, your diet and lifestyle also have an effect on your bone health.

The two periods of your life when calcium consumption most affects your bone health are the first part, when you are growing and developing and the last part, when your ability to absorb calcium and your stores of calcium may be compromised.

Fun Fact: Weight bearing exercise, such as brisk walking, tennis or working out with weights can significantly reduce your risk of developing osteoporosis. This is because when you build heavier muscles, your body responds by building heavier, denser bones to support those heavier muscles. I guess thin is not in!

Healthy Eating Minerals - Upper Limit

The Upper Intake Level for adults that has been established for calcium is 2500 mg per day.

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