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Calcium: A Healing Nutrient Profile

Your body needs this mineral to build strong bones, move muscles and more
Written by 
Canyon Ranch Staff
Canyon Ranch Reviewer: 

What does calcium do?

The most well-known role of the mineral calcium is maintaining strong bones. In fact, 99 percent of the calcium in our bodies is found in our bones and teeth. The remaining one percent does a lot of heavy lifting. Calcium helps our muscles to contract and our nerves to carry messages from the brain to the rest of the body. And because it mediates the dilatation and constriction of our blood vessels, we need to get enough calcium to have normal blood pressure.

Recent research suggests that calcium plays additional roles in our bodies, too. Calcium appears to help prevent esophageal, stomach and colorectal cancer and it may have a protective effect against other cancers, including those of the breast.
 

How much calcium do you need?

This depends on your gender and age. The general recommendations are:

  • 1000 mg for women ages 19 to 50 (this includes women who are pregnant or breastfeeding) and men ages 19 to 70
     
  • 1200 mg for women 51 and older and men 71 and older

Many people don’t get the amount of calcium they need through their diets. All of us require more calcium as we get older in order to withstand the slow bone loss that naturally occurs with aging. This process happens earlier in women: The decline of estrogen during menopause is associated with lower calcium absorption and faster bone thinning. (Strength-training can help combat bone loss.)

If we don’t have enough of the mineral in our blood, our bodies will draw on the calcium “bank” in our skeletons, worsening bone loss and putting us at risk for fractures. People with low bone mass have a condition called osteopenia; those whose bone density is even lower have osteoporosis—by then their bones have become porous and fragile.

Some people are more likely than others to be calcium deficient. Anyone who avoids dairy products, such as vegans and some people who are lactose intolerant, may be low in the mineral. If you fall into one of these categories, you may want to talk to your doctor or nutritionist to find out how you can increase your calcium intake from food or if you might benefit from supplements. 


More: Nutrition for Strong Bones


Where can you get calcium?

Dairy foods are the main source of calcium in our diets, but they’re not the only place you can get the mineral. Some of our favorite foods that contain plenty of calcium:

 

Food

Serving Size

Amount of Calcium (mg)

Sardines

4 oz

495

Nonfat plain yogurt

1 cup

450

Milk    

8 oz

300

Calcium-fortified juice

1 cup

300

Collard greens (cooked)

1 cup

266

Canned salmon

4 oz

223

Turnip greens (cooked)

1 cup

197

Broccoli

1 cup

177

Bok choy (cooked

1 cup

158

Cottage cheese

½ cup

155

Tofu, firm

½ cup

151

Kale

1 cup

94

Almonds

1 oz

75

You can look up the calcium content of other foods by referencing the USDA National Nutrient Database for Standard Reference.  

As with other nutrients, it’s best to get your calcium from food (recent research suggests that calcium from supplements may contribute to blocked arteries). Still, your health care provider may suggest that you take a supplement if your diet does not provide enough calcium. There are two forms of calcium supplements: carbonate and citrate. Check to see which one you’re buying—calcium carbonate is more affordable, but calcium citrate is more easily absorbed without food.

And keep in mind that it’s also important to get enough vitamin D from food and sunshine because your body uses it to absorb calcium. 

 

Reference(s) 
Institute of Medicine
National Institutes of Health