One cup of milk a day is not enough calcium to keep your bones healthy and strong. Calcium needs vary by age, and pregnant and lactating women should try to increase their calcium intake. Some guidelines are:
1,300 mg/day for 9-18 years
1,000 mg/day for 19-50 years
1,200 mg/day after 50
Keeping calcium intake at these levels throughout a lifetimecan protect bone density.
Why do humans need so much calcium?
The short answer is to maintain strong, healthy bones and good general nutrition, as well as to prevent osteoporosis. Ninety-nine percent of the calcium in the body is stored in bones and teeth. The remaining 1 percent is in the blood and soft tissues and is essential for life and health.
Without this 1 percent of calcium, muscles wouldn’t contract correctly, blood wouldn’t clot and nerves wouldn’t carry messages. If the body’s blood-calcium levels are not being amply fed by food intake, the body will leach calcium from the bones. The human body actually tears down and builds bone all of the time in order to make its calcium available for essential functions.
If the body continues to tear down more bone than it replaces over a period of years to get calcium, the bones become weak and break easily. This leads to the crippling bone disease called “osteoporosis,” literally “porous bones” from lack of calcium and other minerals that constitue the structure of bone. Approximately 25 million American women and five million American men have some degree of osteoporosis. The disease will affect one-third to one-half of post-menopausal women. Before the age of 30, more bone is made than lost; after 30, this trend reverses.
Women need to be especially vigilant about calcium. Women make less bone and lose it at a greater rate than men do. A woman’s calcium stores are also drawn on during pregnancy and lactation. Adding to this, women generally live longer than men, giving their bones more time to become brittle, less dense, and prone to fracture.
The two best things to do now to prevent future osteoporosis are:
1.include enough calcium in your diet
2.exercise often, and include weight-
bearing activities in your routine.
A family history of osteoporosis and your body’s ability to absorb calcium are other risk factors for osteoporosis. You have no control over these factors, but you can control how much calcium is in your diet and how much you exercise.
An easy trick for keeping track of the amount of dairy-source calcium in your diet each day is what is known as the Rule of 300’s: Give yourself 300 mg for each cup of milk and yogurt or 1.5 ounces of cheese that you include in your daily diet. If your target intake is 1,000 mg, then you’ll need to add 2 and 1/3 extra servings of dairy products a day.
If drinking 3 and1/3 cups of milk a day does not appeal to you, or if you choose not to consume dairy products for any number of reasons, you can get calcium from a wide range of nondairy sources:
Less than 100mg calcium
1 cup of sweet potatoes or green beans
1 cup of cooked lentils, chick peas, navy or pinto beans
3 ounces of shrimp, crabmeat, or clams
100 to 199 mg calcium
1 cup of cooked dandelion greens or kale
3 ounces of canned salmon with bones
8 oz. tofu
1 Tbsp. blackstrap molasses
1 cup of fortified soy beverage
299 mg calcium
1 cup of cooked broccoli or turnip greens
1 cup of oysters
300+ mg calcium
1 cup of cooked collard greens
8 medium sardines
1 cup of fortified orange juice
Three substances dramatically tax your calcium supply: salt, phosphorous, and caffeine. Regardless of how much calcium you get from your diet, researchers have found that adding a lot of salt to your food or eating high sodium foods can lead to a loss of calcium. Phosphorous has the potential to replace calcium in bones, leading to bones with a weaker structure (most sodas are high in phosphorus). It is widely believed that caffeine may deplete the body of calcium. For every cup of coffee, it appears that the body is be robbed of about 5 mg of calcium.
By eating a calcium-rich diet and exercising regularly it is possible to help ensure a lifetime of strong bones and fend off osteoporosis. If you want to read more, there is a wealth of information on calcium and health online:
is a great general information site, with everything from calcium basics to in-depth explanations.
is part of the Vegetarian Resource Group and has a wealth of ideas on getting enough calcium for vegetarians and vegans.