Hair Regrowth After Treatment for Anorexia Nervosa

Does hair return back to normal ?

It’s a common question given just how how common anorexia nervosa is. The lifetime prevalence of anorexia nervosa in the United States is estimated to be about 1% although some studies have shown rates as high as 4% among women. The rates among men are lower and estimated in most studies to be around 0.1%.

So does hair return back to normal?

Hair density can improve either partly or fully after weight returns into a normal range.  For the vast majority patients 16-25 years of age, it’s a complete improvement. It does, however, take up to 15-18 months to see the maximum improvements although hair shedding slows down considerably and hair starts sprouting as BMI climbs over 18 and especially as BMI moves above 19. Hair density, shine and manageability improves in parallel along with changes in the skin. For women, resumption of regular menstrual cycles is a positive sign that hair is likely to be receiving adequate nutrients but many patients with anorexia nervosa do experience significant improvements in hair density even if menstrual cycles remain irregular.

If there are other diagnoses that have entered the patient’s life over the period of time that the patient has been experiencing anorexia (such as androgenetic alopecia) the hair growth may not be complete. There is a very very low chance of having coexistent androgenetic alopecia in teenagers, and a low chance of this in women 18-25. The chances of coexistent androgenetic alopecia increase with age.  The diagnosis of androgenetic alopecia can be confirmed by a practitioner skilled in the diagnosis of androgenetic alopecia. Treatment of the androgenetic hair loss will also help to maximize the amount of improvement the patient will have. 

I have witnessed many, many patients through the years improve the hair density in dramatic ways after getting help for anorexia nervosa. It does take a long time so one need to set a time line that extends 18 months into the future.  It’s easy to get discouraged and supports are needed in all aspects of the patient’s continued recovery. The first signs are a reduction in shedding followed by sprouts of hair all over the scalp. The sprouts of hair in the front are referred to by some as “recovery bangs” and are seen in any patent with a resolving telogen effluvium (and not exclusively to recovery from anorexia nervosa).

How I evaluate hair loss in patients with anorexia nervosa.

A complete scalp examination is helpful to exclude other issues such as androgenetic alopecia and seborrheic dermatitis. Rarely other hair issues such as traction alopecia and trichotillomania are present but this is not common. Most patients have a classical telogen effluvium.

I encourage my own patients to get some basic blood tests at the beginning of their recovery in order to know if there are any immediate deficiencies or abnormalities that need correcting. These blood tests include CBC, TSH, AM cortisol, ferritin, albumin, AST, ALT, creatinine, zinc, RBC folate, magnesium, selenium, B12, 25 hydroxy vitamin D and vitamin C. I often advise 12 months of a multivitamin supplement along with vitamin D 1000-2000 IU (in addition to correcting any deficiencies) to support recovery along with healthy eating.

Treatment of any coexisting seborrheic dermatitis (if present) is important. I encourage patients to shampoo the hair regularly.

The changes in the hair density can be dramatic.