“Your labs look fine” can be some of the most harmful words in eating disorder care.
People often find it surprising when I say that labs are often normal, even when someone is very sick with their eating disorder. That being said, bloodwork gets a lot of attention, and it’s easy to see why. It gives doctors something concrete to do, and they are objective. However, in eating disorder treatment, they are often misleading.
Over the years, patients and families have told me again and again that when they went to their doctor with concerns about an eating disorder, they were reassured. They were told, “Your labs look fine, and there is nothing to worry about.” While this sounds harmless, it isn’t. This reassurance frequently results in a delay of care and potentially worsens the disease, especially given that early intervention is linked to a better prognosis.
There are two specific reasons why we should check labs in someone with an eating disorder who has lost weight.
First, we want to make sure we aren’t missing another cause for weight loss. Children and adolescents shouldn’t be losing weight. When they are losing weight, we need to be sure there aren’t other reasons why. Eating disorders are a diagnosis of exclusion, and we must rule out conditions like diabetes, thyroid disease, inflammatory bowel disease, and celiac disease.
The second reason to check labs is to evaluate for the medical complications of an eating disorder. Weight loss can impact electrolytes, blood counts, vitamin D levels, iron levels, hormone levels, and more.
However, labs do not necessarily tell us how sick someone is. The reality is that labs are often normal when someone is very sick. The wise body does everything it can to protect vital functioning and finds a way to compensate for malnutrition. Therefore, the bloodwork often looks reassuring. Someone can be medically hospitalized with a critically low heart rate and still have normal labs.
Unfortunately, there is real potential harm in saying, “Good news, the labs look good.” For a worried parent who has been witnessing disordered eating behavior, it can give them the message that their concern was unwarranted. And, for the child suffering from the eating disorder, who is feeling ambivalent about getting treatment and working toward recovery or continuing the eating disorder, it can send a message to them that they are not sick enough, and they should keep going.
So, how should we approach the labs? Labs are a small part of the clinical picture. We need to treat them as part of the story and history, along with the trajectory on the growth chart, the resting heart rate and orthostatic vital sign changes, the symptoms, and the history from the patient and their family. And we should follow along over time, since normal labs one day doesn’t mean they will stay normal in the setting of an eating disorder.
For the clinician, if a patient or parent is concerned about eating behaviors and labs are normal, consider saying, “Labs are typically normal in people who have eating disorders, even when someone is very sick. Normal results are good to see, but they don’t tell us that your health isn’t being affected.”
For the parent, if the clinician reassures you that the labs are normal but you are still concerned about your child’s eating behaviors or health, you can ask to speak to an eating disorder specialist and have your child re-evaluated. You heard it from this doctor: Don’t stop at the normal labs, and listen to your gut.
