Light Menstruation From Losing Weight by Exercising

Losing too much weight with exercise can lead to irregular or absent periods.
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Periods aren’t all that convenient, but they’re certainly necessary for life and health. That’s why women who engage in high levels of exercise need to keep a close eye on their body weight and make sure it doesn’t dip too low. Dropping too many pounds through exercise can affect your life-giving menstruation cycle and possibly cause it to cease altogether, putting you at risk for a range of health problems both physical and mental.

Menstruation and Exercise

    If you compete in sports or train hard for running or cycling events, you may lose enough weight to experience light periods or advance to a condition called amenorrhea in which your body stops menstruating altogether. A weight that is too low for your body’s natural point of health interrupts hormonal functions in your body, including the production of gonadotropin releasing hormone (GnRH), which causes the pituitary gland to release the hormones that control your menstrual cycle. These hormones regulate the ovaries and, when disrupted, can lead to abnormal or ceased ovulation.

Health Problems

    When you exercise to a weight that is too low for your body’s genetics and begin experiencing abnormal or absent periods, you are at risk for health problems such as osteoporosis, underdeveloped breasts, stress fractures, thinned hair and even depression and anxiety. Without ovulation, you also eliminate your ability to become pregnant. Until your cycle returns, you won’t be able to conceive, and even then your risk of fertility problems increases.

Regaining Menstruation

    With your body’s ability to repair itself, you can potentially restore your menstruation by reducing your exercise by 5 to 15 percent to start and by focusing on adequate nutrition. If you have been restricting fat from your diet, it's important to resume eating healthy fats such as nuts, peanut butter, avocado, fish and olive oil. Eating red meat two or three times a week can also encourage menstruation, as vegetarian women are five times more likely to have menstrual problems than meat eaters.


    Depending on your level of training, it can take between two to six months or more to restore regular cycles, and further alterations to your training regimen may be necessary. Because abnormal or absent periods are a medical issue, it’s important to work with a physician and registered dietitian to ensure your total health restoration. In some cases, your doctor may prescribe medications such as oral contraceptives, which contain low levels of hormones and can help your body resume regular menstruation. If the condition is heightened or related to an eating disorder, it may also be necessary to seek treatment from a mental health professional.

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