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There are many ways you can help protect your bones from osteoporosis. In childhood, new bone is added faster than old bone is removed so your bones become larger and denser as you grow. Adolescence is the most important bone-building period. Once you become a teenager and reach your full height, your bones become more dense. The thicker your bones are to start with, the less likely they are to eventually become weak and prone to fracture.

Getting plenty of calcium, vitamin D and physical activity are crucial to your bone health. You are never too young or too old to start. As a child and teenager, calcium, vitamin D and exercise help you build strong bones. As an adult, they help keep your bones strong and prevent osteoporosis. If you have osteoporosis, they can help slow the rate of bone loss and even increase your bone density.  


Women can help protect themselves from osteoporosis by following Canada’s Food Guide to ensure an adequate intake of key nutrients. It is particularly important to get enough calcium and vitamin D.

Calcium and vitamin D
Almost every cell in your body needs calcium. Your heart, nerves, muscles, blood, colon and bones need calcium on a daily basis.

Your bones depend on calcium for strength. About 99 per cent of your body's calcium is stored in your bones. The rest circulates in your blood and takes part in important functions. If there is not enough calcium circulating in your blood, the body takes the calcium it needs from your bones. The bones act like a bank, where you deposit calcium daily and withdraw it as needed. When calcium is taken from your bones, your bones weaken and become more fragile.

Vitamin D is also vital to the health of your bones:

  • it increases your body’s ability to absorb calcium by 30 to 80 per cent, thereby making your bones stronger
  • it helps strengthen your muscles
  • it has been shown to reduce older adults’ risk of falling by more than 20 per cent
  • some initial research has also identified a link between vitamin D deficiency and musculoskeletal pain

Calcium and vitamin D recommendations
Osteoporosis Canada
recommends that adults between the ages of 19 and 50, including pregnant or lactating women, get 1,000 mg of calcium and 400 to 1,000 international units (IUs) of vitamin D3 daily. Adults over the age of 50 should get 1,200 mg of calcium and 800 to 2,000 IUs of vitamin D daily.

Food sources of calcium
The best way to get the calcium we need is from food.

Each serving below provides 300 mg of calcium:

Milk – skim, 1%, 2% or whole milk

1 cup/250 mL

Cheese – firm cheeses, such as brick, cheddar, colby, edam, gouda or mozzarella (regular or low-fat)

1½ oz/45 g

Cheese – ricotta

½ cup/125 mL

Home-made macaroni and cheese

2 cups/500 mL

Salmon, canned with bones

½ of a 7.5 oz can

Sardines, canned with bones

7 medium fish


¾cup/188 mL

Frozen yogurt

1 cup/250 mL

Blackstrap molasses

2 tablespoons/1 fluid oz

Tofu – regular, set with calcium sulfate

1 cup/250 mL

Tofu – firm, set with calcium sulfate

½ cup/125 mL

Rice beverage, calcium-fortified

1½ cups/375 mL

Soy beverage, calcium fortified

1½ cups/375 mL

Soybeans, cooked

2 cups/500 mL

Bok choi, cooked

1 cup/250 mL

Kale, cooked

1½ cups/375 mL

Mustard greens, cooked

1½ cups/375 mL

Turnip greens, cooked

¾ cups/188 mL

Broccoli, cooked

4 cups/1 L


¾ cup/188 mL

Figs, dried


Orange juice, calcium-fortified

1 cup/250 mL





  • Bowes & Church's Food Values of Portions Commonly Consumed. Philadelphia, PA: J.B. Lippincott Co., 1994.
  • Osteoporosis Canada: Building Better Bones: A Guide to Active Living.
  • Main, J. Bone Vivant! Calcium-Enhanced Recipes and Bone Building Exercises. Toronto: Macmillan Canada Inc., 1993.

The best source of calcium is milk and calcium-rich foods. Consider supplements if it is impossible to get enough calcium from your diet. Your doctor or a registered dietitian can recommend the amount and type of calcium supplements you need to take.

Sources of vitamin D
Vitamin D occurs naturally in very few foods: cod liver oil, fatty fish, such as salmon, tuna, mackerel or sardines, and egg yolks. Vitamin D is also added to milk and some rice and soy beverages. For adults over 50 years of age, it is almost impossible to get the recommended daily intake of vitamin D through food sources alone.

Sunshine helps your body to produce vitamin D. Ten to 15 minutes exposure on your hands and face without sunscreen every day is recommended. In the fall and winter months, the sun becomes weak in Canada and does not allow us to get as much of the vitamin. For this reason, your doctor may recommend vitamin D supplements.

Be aware that it is possible to get too much vitamin D. How much is too much is the subject of debate: Health Canada advises against taking more than 2,000 IUs a day whereas others say anything under 10,000 IUs is safe.

Physical activity

Women achieve their maximum bone mass in their teenage years. The more bone mass you accumulate before that age, the more likely you are to have healthy, strong bones later in life. Yet Canada’s Report Card on Physical Activity for Children and Youth for 2008 shows that less than half of children in Canada get the amount of exercise they need each day for healthy growth and development. And girls tend do less physical activity than boys: only 36 percent of girls are meeting physical activity guidelines.

Weight-bearing activity
Examples of weight-bearing activities include:

  • climbing stairs
  • walking
  • Tai Chi
  • dancing
  • hiking
  • aerobics and step classes
  • jogging
  • racquet sports, like tennis
  • skipping rope
  • lifting weights

Low-impact activities, such as cycling, swimming and using an elliptical machine, are great forms of exercise but they are not weight-bearing.

Muscle strengthening activity
Activities that strengthen your muscles also make your bones denser, and improve your posture and balance. Muscle strengthening exercises can be done at home or in a gym by

  • using strap-on velcro ankle and wrist weights
  • lifting free weights
  • using weight machines
  • doing exercises that strengthen your core
  • doing exercises that use your own body weight to exercise your muscles (such as push-ups, curl-ups, lunges and squats)

Consult an exercise specialist to determine which exercises are most appropriate for you.


To promote the health of our bones and prevent osteoporosis, we can also quit smoking, and limit the amount of caffeine and alcohol we consume.

Smoking can cause women to reach menopause as much as five years earlier, which has a direct effect on bone loss. Smoking can also reduce your body’s ability to absorb calcium. Regardless of your age, quitting smoking is good for your bone health.

Caffeine is a diuretic. This means you go to the bathroom more when you drink coffee, tea or carbonated drinks that contain caffeine. As a result, you lose more calcium in your urine.

Drinking moderate amounts of caffeine is safe, but try to avoid having more than three cups of coffee a day.

We don't fully understand the relationship between alcohol and bones, but we do know that alcohol can have a toxic effect on the liver, and may interfere with calcium absorption. Alcohol is also a diuretic so it increases the amount of calcium lost in the urine. Try to drink no more than one or two alcoholic beverages a day.


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  • A publication of:
  • Women's College Hospital