By Nancy Clark, MS, RD, CSSD
You have amenorrhea if you're a woman runner who previously had regular menstrual periods but currently have stopped menstruating.
You may believe this condition relates to being too thin and running too much, but that may be incorrect.
Fifty to eighty percent of female athletes do have regular menses. Leanness and exercise are not simple explanations to the complexities of amenorrhea.
The question arises: Why are you experiencing menstrual problems when other similarly active and lean women menstruate regularly?
The answer may relate to your eating habits. If you are struggling to achieve an unusually low weight, you may be eating inadequate calories as well as protein, fat, and other nutrients needed to support regular menstruation, health and performance.
Loss of menses can be a red flag for restrictive eating behaviors. "Absence of at least three consecutive menstrual cycles" is part of The American Psychiatric Association's definition of anorexia.
Although you may consider amenorrhea a desirable benefit of exercise because you no longer have the hassles of monthly periods, amenorrhea can lead to medical problems:
How to Resolve the Problem of Amenorrhea
- a 2 to 4 times higher incidence of stress fractures that can hinder your ability to exercise.
- premature osteoporosis that weakens your bone health today and can easily get worse with aging.
To resume menses, you need to correct an energy imbalance. This can mean running 5 to 15% less and eating a little more. Some amenorrheic athletes have resumed menses without gaining weight; others do so after having gained less than 5 lb. (some of which is muscle).
This small weight gain does not cause a drastic change in physical looks but can help you be healthier and perform better. If you believe poor eating may contribute to your menstrual problem, the following tips may help you resume menses or, at least, rule out nutrition-related factors.
- Throw away the scale.
Don't force your body to weigh a self-selected number on the scale. Rather, honor your genetic weight. To assess your body's natural weight, visualize yourself at a family reunion and compare your body to the physiques of your family members.
If you're far thinner than your family, take note. Perhaps you should stop trying to remodel your body into a size that is abnormal for your genetics?
The general rule to determine an appropriate weight (plus or minus 10%) for your height is:100 pounds for the first five feet of height plus five pounds per inch thereafter.
For example, a 5' 6" woman could appropriately weigh 130 ±13 lbs. Yet, you need to factor in your bone structure (petite, large), weight history (highest, lowest, and "comfortable" weight that you can easily maintain), musculature, and your percent body fat.
Rather than trying to achieve a predetermined number on the scale, let your body settle at a weight you can comfortably maintain.
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- If you have excess fat to lose, don't crash diet.
Instead, moderately cut back on your calorie intake by only about 20%. Severe dieting commonly results in amenorrhea, suggesting amenorrhea may be your body's way to adapt to a calorie deficit and conserve calories.
By following a healthy reducing program, you will not only have greater success with long-term weight loss, but will also have energy to run well.
- Eat when you are hungry, stop when you are content.
Practice this simple rule for eating if you are at an appropriate weight. You were born with a natural ability to regulate your food intake but probably lost it as you began to diet. Now, you may have to relearn how to listen to your body.
Rather than feel hungry all the time and constantly obsess about food, listen to your body's requests for more fuel and respond appropriately by eating larger meals.
Some research suggests amenorrheic athletes consume about 500 fewer calories than their regularly menstruating counterparts.
Other research questions this data and suggests amenorrheic women who maintain their weight do indeed eat the calories they deserve but they tend to follow non-traditional eating patterns (undereating during the day, overeating at night, splurging on weekends). This chaos may interfere with internal health and regular menses.
If you have erratic eating patterns that stem from a fear of getting fat, remember that eating balanced meals on a regular schedule is your best bet for achieving and maintaining an appropriate weight for optimal health. A dietitian can help you stabilize your eating.
- Eat adequate protein.
Some research indicates amenorrheic athletes tend to eat less protein than their regularly menstruating counterparts. A safe protein intake is 0.5 to 0.75 grams per pound of body weight (1 to 1.5 gm pro/kg).
This is higher than the current 0.4 gm pro/lb recommended for sedentary people and allows a margin of safety to reduce the possibility of a protein deficient diet.
An appropriate protein intake for a 120 pound athletic woman is 60 to 90 grams--the equivalent of three to four 8-ounce servings of low fat milk or yogurt plus four to six ounces of meat, fish, chicken, or other protein-rich food (beans, tofu) per day.
If you do not eat meat, note you need more protein than supplied by a diet based on fruits, vegetables, salads, breads, and grains.
- Consider including small portions of red meat two or four times per week.
Surveys of amenorrheic runners suggest they eat less red meat (and are more likely to be vegetarians) than their regularly menstruating peers. Even though some red meats can have a slightly higher fat content than do chicken or fish, an overall low fat sports diet can and should accommodate some fat. Getting a little fat via 2 to 4 small servings a week of lean meats may invest in regular menses.
Vegetarian diets are associated with amenorrhea not only among athletes but also the general population. An estimated 27% of vegetarians lack regular menses as compared to only 5% of women who eat meat.
Why? Possibly because vegetarian women eat more calories from fiber-rich foods and this reduces their estrogen. The high fiber intake common to vegetarian diets may also affect calcium absorption, another concern for the amenorrheic woman who should optimize calcium intake to maintain bone density.
As a woman runner, you might want to take a simple iron supplement such as a multi-vitamin and mineral pill if you don't eat lean red meats. Supplementing your diet may help protect you from becoming anemic.
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- Eat at least 20% of your calories from fat.
Some women have the exaggerated perception if they eat fat, they will get fat. Consequently, they skimp on meat and other protein-rich foods because they are afraid of eating fat. Although excess calories from fat are easily fattening, eating 20 to 30% of total calories from fat is appropriate for a heart-healthy sports diet.
For most women runners, this translates into about 40 to 60+ grams of fat per day and allows lean beef, peanut butter, (low fat) cheese, salmon, nuts, and other wholesome protein-rich foods that provide balance to a sports diet. Clearly, this moderate approach offers big nutritional advantages over attempts to eat a very limited no-fat diet.
- Maintain a calcium-rich diet.
Amenorrhea weakens bones. Hence, you should choose a high calcium diet to help maintain bone density. Because you build peak bone density in your teens and into early adult years, your goal should be to protect against future problems of osteoporosis by eating calcium-rich foods today.
A safe target is 1,000 to 1,500 mg calcium per day, the equivalent of three to four servings of (low fat) milk, yogurt, and cheese, or generous amounts of other calcium-rich foods such as tofu, broccoli, kale, dark green leafy vegetables, and calcium-enriched orange juice and soy milk.
Although you may hesitate to spend your calories on milk, remember that milk is not an "optional fluid" but rather a fundamental food. Milk and yogurt contain many important nutrients other than calcium, such as riboflavin (to help convert food into energy) and protein (to protect muscles). Yogurt often has more calcium than milk, and is a fine alternative to drinking glasses of milk.
If you are eating a very high fiber diet that includes generous amounts of bran cereal, fruits, and vegetables, you may have an even greater need for calcium because the fiber may interfere with calcium absorption. Be sure to eat calcium-rich foods with each meal plus snacks.
Calcium is only one factor that affects bone density. Other factors include:
- your genetic predisposition to osteoporosis.
- your weight. Heaviness increases bone density.
- your exercise program. Weight-bearing (e.g. running) and strengthening exercises protect your bones.
- how much estrogen your body produces. Estrogen protects against calcium loss.
Your bones benefit from the protective effect of running, but this does not compensate for lack of calcium nor lack of estrogen. Is There Long Term Damage with Amenorrhea?
Amenorrheic women who resume menses can restore some of the bone density lost during their months of amenorrhea but not all of it, unless they are teenagers. Hence, your goal should be to eat wisely and resolve the problem quickly.
If you struggle with making the nutrition and exercise changes that would enhance resumption of menses, you might want to look at the bigger picture. That is, why do you so rigidly control your diet, weight, and exercise program?
This desire for control, in addition to a drive for perfection (having the perfect diet and the perfect weight) may be entangled with life issues that could be better addressed by a counselor than a nutritionist or gynecologist.
Copyright: Nancy Clark, MS, RD, CSSD
Nancy Clark's new Sports Nutrition Guidebook (2008), Food Guide for Marathoners, and Cyclist’s Food Guide are available at her website
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