Eating Disorders and Low Heart Rate

By Mark Warren, MD, Chief Medical Officer, The Emily Program

An important topic that comes up relatively frequently with my patients in eating disorder treatment is whether those with low heart rates are at risk. The answer is absolutely yes. A low heart rate is a very significant risk and requires immediate attention.

There is a belief held by some that low heart rates are normal – and safe – in adolescents who are athletes. However, this is not supported by evidence and, in fact, it is almost certainly untrue.

The notion of an athlete’s heart comes from a specific subgroup of the population whose hearts are larger, stronger, and more effective at pumping blood than the rest of us. This is quite different from adolescents with eating disorders.

When patients with anorexia suffer significant weight loss and low heart rates, which doctors refer to as bradycardia, it results in a shrinking of the heart size. In this way, the heart is protecting itself in a malnourished state. Functionally, this is the exact opposite of an athlete’s situation. With eating disorders, low heart rates are not signs of strong hearts instead, they are signs of weak hearts.

Because eating disorders are rarely taught throughout medical training, it is quite common to meet professionals who are not well educated on the literature regarding medical complications from eating disorders. It is up to us in the field to help bring this information to primary care physicians and other providers.

It is critical that if you or someone you love has bradycardia you seek treatment immediately, both initially to correct the low heart rate and then more expansively to treat the eating disorder itself. Cardiac issues are the No. 1 cause of early mortality from eating disorders. But with treatment, they can be prevented.