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Reviewed January 2011
Are you exercising too much? Eating too little? Have your menstrual periods stopped or become irregular? If so, you may be putting yourself at high risk for several serious problems that could affect your health, your ability to remain active, and your risk for injuries. You also may be putting yourself at risk for developing osteoporosis, a disease in which bone density is decreased, leaving your bones vulnerable to fracture (breaking).
Some athletes see amenorrhea (the absence of menstrual periods) as a sign of successful training. Others see it as a great answer to a monthly inconvenience. And some young women accept it blindly, not stopping to think of the consequences. But missing your periods is often a sign of decreased estrogen levels. And lower estrogen levels can lead to osteoporosis, a disease in which your bones become brittle and more likely to break.
Usually, bones don't become brittle and break until women are much older. But some young women, especially those who exercise so much that their periods stop, develop brittle bones, and may start to have fractures at a very early age. Some 20-year-old female athletes have been said to have the bones of an 80-year-old woman. Even if bones don't break when you're young, low estrogen levels during the peak years of bone-building, the preteen and teen years, can affect bone density for the rest of your life. And studies show that bone growth lost during these years may never be regained.
Broken bones don't just hurt—they can cause lasting physical malformations. Have you noticed that some older women and men have stooped postures? This is not a normal sign of aging. Fractures from osteoporosis have left their spines permanently altered.
Overtraining can cause other problems besides missed periods. If you don't take in enough calcium and vitamin D (among other nutrients), bone loss may result. This may lead to decreased athletic performance, decreased ability to exercise or train at desired levels of intensity or duration, and increased risk of injury.
Girls and women who engage in rigorous exercise regimens or who try to lose weight by restricting their eating are at risk for these health problems. They may include serious athletes, "gym rats" (who spend considerable time and energy working out), and girls and women who believe "you can never be too thin."
Here are some signs to look for:
If you recognize some of these signs in yourself, the best thing you can do is to make your diet more healthful. That includes consuming enough calories to support your activity level. If you've missed periods, it's best to check with a doctor to make sure it's not a sign of some other problem and to get his or her help as you work toward a more healthy balance of food and exercise. Also, a doctor can help you take steps to protect your bones from further damage.
First, be supportive. Approach your friend or teammate carefully, and be sensitive. She probably won't appreciate a lecture about how she should be taking better care of herself. But maybe you could share a copy of this fact sheet with her or suggest that she talk to a trainer, coach, or doctor about the symptoms she's experiencing.
Girls and women who may be dieting often drink diet sodas rather than milk. Yet, milk and other dairy products are a good source of calcium, an essential ingredient for healthy bones. Drinking sodas instead of milk can be a problem, especially during the teen years when rapid bone growth occurs. If you (or your friend) find yourself drinking a lot of sodas, try drinking half as many sodas each day, and gradually add more milk and dairy products to your diet. A frozen yogurt shake can be an occasional low-fat, tasty treat. Or try a fruit smoothie made with frozen yogurt, fruit, or calcium-enriched orange juice.
Years ago, it was not unusual for coaches to encourage athletes to be as thin as possible for many sports (e.g., dancing, gymnastics, figure skating, swimming, diving, and running). However, many coaches now realize that being too thin is unhealthy and can negatively affect performance. It's important to exercise and watch what you eat. However, it's also important to develop and maintain healthy bones and bodies. Without these, it will not matter how fast you can run, how thin you are, or how long you exercise each day. Balance is the key!
Brittle bones may not sound as scary as a fatal or rare disease. The fact is that osteoporosis can lead to fractures. It can cause disability.
Imagine having so many spine fractures that you've lost inches in height and walk bent over. Imagine looking down at the ground everywhere you go because you can't straighten your back. Imagine not being able to find clothes that fit you. Imagine having difficulty breathing and eating because your lungs and stomach are compressed into a smaller space. Imagine having difficulty walking, let alone exercising, because of pain and misshapen bones. Imagine constantly having to be aware of what you are doing and having to do things so slowly and carefully because of a very real fear and dread of a fracture—a fracture that could lead to a drastic change in your life, including pain, loss of independence, loss of mobility, loss of freedom, and more.
Osteoporosis isn't just an "older person's" disease. Young women also experience fractures. Imagine being sidelined because of a broken bone and not being able to get those good feelings you get from regular activity.
How much calcium do I need? It's very important to your bone health that you receive adequate daily amounts of calcium, vitamin D, phosphorus, and magnesium. These vitamins and minerals are the most influential in building bones and teeth. This chart will help you decide how much calcium you need.
|9 to 13||1,300|
|14 to 18||1,300|
|19 to 30||1,000|
Source: Food and Nutrition Board, Institute of Medicine, National Academy of Sciences, 2010.
Where can I get calcium and vitamin D? Dairy products are the primary food sources of calcium. Choose low-fat milk, yogurt, cheeses, ice cream, or products made or served with these choices to fulfill your daily requirement. Three servings of dairy products per day should give you at least 900 mg (milligrams) of calcium. Green vegetables are another source. A cup of broccoli, for example, has about 136 mg of calcium.
Milk and dairy products. Many great snack and meal items contain calcium. With a little planning and "know-how," you can make meals and snacks calcium-rich!
What are other sources of calcium? Many foods you already buy and eat may be "calcium-fortified." Try calcium-fortified orange juice or calcium-fortified cereal. Check food labels to see if some of your other favorite foods may be good sources of calcium. You also can take calcium supplements if you think you may not be getting enough from your diet.
This publication contains information about medications used to treat the health condition discussed here. When this fact sheet was printed, we included the most up-to-date (accurate) information available. Occasionally, new information on medication is released.
For updates and for any questions about any medications you are taking, please contact
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