Eating Disorders and Hypothalamic Amenorrhea

Hypothalamic Amenorrhea is a commonly occurring medical condition in women of childbearing age with eating disorders. The body enters survival mode, periods stop, and women will not be able to reproduce. Learn more about what causes it, the consequences, and how it is treated.

When an eating disorder is present, the most common cause of missing a period is hypothalamic amenorrhea (HA). The hypothalamus is an area of the brain that plays a central role in maintaining the balance of body systems. It receives input from throughout the body in the form of hormones and chemicals; it responds by secreting hormones that affect other organs including those involved in reproduction.

When the hypothalamus receives a signal that something in the body is off-kilter and needs addressing, it rebalances the body by releasing hormones into the bloodstream. Sometimes, when things go wrong in the body, the hypothalamus can’t restore balance; such is the case with hypothalamic amenorrhea.

A diagnosis of HA is only made after other causes of amenorrhea are ruled out. However, in the case of an eating disorder, HA is a likely cause, even when weight is not extremely low.

The contributing factors to hypothalamic amenorrhea include energy imbalance, food restriction, weight loss, exercise, stress, and genetics. Each person expresses these factors differently, and each factor contributes in varying degrees to the development of HA. Let’s look at each in turn.

According to Nicola Rinaldi—a biologist who both experienced and ran an online forum for women who had HA—and colleagues, “In the vast majority of cases, the primary driver is an energy deficit from undereating and overexercising regardless of body size.” Our bodies need fuel in order to function optimally. 

Restricting the range of food eaten can contribute to the development of HA. Low-fat diets are a common culprit – our bodies need fat to function optimally.

Low weight and body fat percentage, as well as a history of prior weight loss, can be contributing factors. It is important to point out that some women lose their period at higher weights than others. Each person’s body appears to have a different weight at which it will function optimally—it is reasonable to believe that as with anything else in the natural world, people’s bodies naturally come in different sizes and shapes. Having lost a significant amount of weight (10 pounds or more)—even years in the past—increases the risk for HA. 

A common misconception is that one needs to be extremely emaciated to lose one’s period. This has been shown to be untrue: in a study of 286 women with HA, the body mass index (BMI) at which they lost their period ranged from 15 to 25, with a median of 19. 

Exercise contributes to HA by burning energy and leaving less available for body functions and also by increasing stress hormones including cortisol.  

Chronic stress can lead to increased production of cortisol. High levels of cortisol also appear to stop the hypothalamus from releasing reproductive hormones. 

There is genetic variability in the various factors that determine the sensitivity of our reproductive systems to energy deficits and stress. This explains why some people can continue to menstruate at relatively low weights, while others will lose their period at a much higher weight. 

It is estimated that HA affects approximately 1.62 million women between the ages of 18 and 44 in the United States and 17.4 million women worldwide. 

The presence of secondary amenorrhea (defined as the cessation of regular menses for three months or the cessation of irregular menses for six months) used to be a diagnostic criterion for anorexia nervosa but was removed in the latest update of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).

While the prevalence of amenorrhea is high among adolescent and premenopausal women with anorexia, it has been removed as a criterion for multiple reasons. First, the predisposition to hormone dysregulation is variable—some women with very low weights continue to menstruate. Second, this criterion is simply not useful across the broader spectrum of those susceptible to anorexia, including men and females who are premenarchal, post-menopausal, or taking birth control pills. 

HA results in estrogen deficiency and the cessation of the menstrual cycle in young premenopausal women. This, in turn, has significant effects on the body’s cardiac, skeletal, psychological, and reproductive system. These effects can mimic menopause and all the physical and psychological changes that it works on the body.

One difficulty is that many women with HA, due to lack of bothersome symptoms, often feel quite well. Thus, they may be reticent to seek treatment.

Longer-term consequences include higher cardiovascular disease risk and threatened bone health. Low estrogen suppresses bone production, which can lead to bone loss, osteopenia (loss of bone calcium), and increased risk of fractures. Amenorrhea can cause bone loss in as little as six months. HA is also implicated in increasing depression and anxiety. HA can cause an absence of ovulation and infertility during a woman’s peak reproductive years. 

The goal of treatment for HA is to reestablish a regular ovulatory menstrual cycle. Appropriate weight gain appears to be the most important predictor of menstrual resumption. Typically, all the contributing factors must be addressed: energy imbalance, food variety, excessive exercise, low weight, and stress. 

Many women with HA who present to a medical provider are prescribed birth control pills. This is unfortunate. While this is an estrogen replacement that will provide a fake bleed, it does not solve the underlying problem or help the resumption of normal natural hormone activity. The underlying HA still needs to be addressed and birth control pills may only mask the problem. 

Furthermore, if you are already on birth control pills, be aware that the artificial period you get from birth control pills does not provide an accurate indicator of your health. You won’t be able to tell whether you’d menstruate on your own and whether HA is an issue for you until you go off them. “If you’re getting your period only because you are on birth control pills, it doesn’t count,” (Rinaldi, 2019, p. 12). Studies have shown that birth control pills do not help prevent further bone loss. Therefore, birth control pills should not be used as a treatment for HA. 

It should go without saying that if your HA accompanies an eating disorder, you should be getting help from a professional. Working with a therapist, dietitian, and medical doctor experienced with eating disorders can help you recover from HA. Eating disorder treatment will likely include the goals of eating more, exercising less, and learning to manage stress better.

If you believe you are recovered from your eating disorder, but your period has not yet resumed, you are encouraged to follow the recommendations below. Some women may think they are recovered, but still have more work to do in terms of increasing weight or food flexibility. 

Recovery requires eating enough—not only to adequately fuel current energy needs but to also to make up for the history of under-fueling. For most women with HA, recovery requires eating at least 2500 kcal per day. Eating a greater variety of foods, from all macronutrient groups including fats and starches, seems to stimulate more hormone production. Full-fat dairy is particularly good for stimulating ovulation. 

You may not want to gain weight, thinking that you already feel healthy. However, if you are not menstruating due to HA, your body disagrees with you. Try gaining 5 pounds and see what happens. You may be pleasantly surprised to see your cycles resume. Although healthy body weights vary greatly, most women with HA need to obtain a BMI of 22 to 23 or even higher to resume menses.

Recovery is also facilitated by eliminating intense exercise. Faster recovery is associated with cutting exercise entirely. Slower recovery is achieved when exercise is reduced in intensity or duration or both. Running seems to be the exercise that makes it hardest to regain natural menstrual cycles. 

Research shows that reducing stress can help with recovering from HA. However, you might be managing your anxiety in ways that can contribute to HA—strenuous exercise or restrictive eating to deal with body image. Learning other coping skills such as relaxation, mindfulness, distress tolerance, and sedentary joyful activities can help complete the recovery puzzle. 

The length of time it takes to resume regular menses varies based on factors such as rate of weight gain, exercise level, stress level, age, and genetics. One study found no correlation between the length of time a period had been missing and the length of time to recovery. 

One survey of women with HA tracked how long it took for women to regain their cycle after making lifestyle changes and found that success rates increased over time:

• After three months: 24 percent
• After four months: 34 percent
• After six months: 57 percent

If you’ve lost your period, you may think there’s no reason to be concerned with your health. However, the absence of regular cycles is not normal. You are encouraged to see a medical professional and ask about the possibility of a diagnosis of hypothalamic amenorrhea.

You can reduce irreversible damage to your bones by seeking help and following the lifestyle change suggestions above. If you are on birth control pills and don’t know if you’d still menstruate without them, you are encouraged to speak to your treatment providers about whether you are truly at a healthy weight.