Hair Loss and Obesity: Five Considerations on World Obesity Day

Obesity and Hair Loss: What do hair specialists need to know?

Today is World Obesity Day. We’re all familiar with the general use of the terms “overweight” and “obese”, but medical professionals actually define the terms quite precisely. Overweight is defined as a body mass index (BMI) above 25. Obesity is defined as a body mass index (BMI) above 30. BMI is calculated as weight in kilograms (kg) divided by height in meters squared (m2).

About 24 % of people in Canada are obese and about 33 % of people in the US are obese. These numbers represent a doubling since the 1980s. Worldwide, about 500 million people are obese and this its expected to rise to 1 billion by 2030. Behavioural factors, genetics and the environment all have a role in obesity. It’s a subject of intense research.

Five things Hair Specialists Should Remember about Obesity

It’s important to recognize many things about the patient. It’s important to recognize if a patient is tall or short. It’s important to recognize if they wear glasses or not. It’s important to recognize if the patient is overweight, obese or underweight. It all matters.

1. Obesity may be an important clue to the underlying cause of hair loss.

Obesity can be an important clue to potential causes of hair loss. This may differ across different ages.

In young children, obesity and abnormal growth may be clues to an underlying health issue - especially certain genetic and/or endocrine issues.  For example, I tell junior doctors that I work with that the only way they are even going to think about a possible diagnosis of late onset congenital adrenal hyperplasia in an obese child who is brought in by parents regarding concerns about hair loss is by recognizing that the child is heavier and taller than their classmates. Obesity in children who present to clinic with hair loss must never go overlooked - as it’s very often relevant to the cause of hair loss. Every young child and teenager with hair loss needs a careful workup.

Obesity in patients with hair loss is potentially a clue to an underlying endocrine issue. This is true for both men and women. Obesity in female patients age 15-25 years of age who come into clinic with concerns about hair loss might be a sign of an underlying hormonal disorder. Issues such as polycystic ovarian syndrome, thyroid disorders, Cushing syndrome all need to be considered.

In polycystic ovarian syndrome, the hyperandrogenism drives obesity, insulin resistance, acne and androgenetic alopecia. I’ve reviewed PCOS in other articles, but it’s important to not to miss this diagnosis. Women with PCOS typically have irregular periods and may have acne, hair growth on the face. In the United States, about 80 % of women with PCOS are overweight or obese.

In some cases, obesity can reflect poor intake of micronutrients necessary to support health hair. Deficiencies of vitamin D, biotin, thiamine and vitamin C have been associated with obesity. These deficiencies can affect hair growth if severe.

Obesity and thyroid disease are also known to be closely linked. In fact, many people in general public have come to view hypothyroid states as being a key cause of obesity. Recent data suggests that obesity may also causes thyroid disease and even trigger thyroid autoimmunity. All clinicians need to be aware of the possibility of thyroid dysfunction in obese patients. This type fo thyroid dysfunction can sometimes be the cause of hair loss.

2. Obesity may be a contributor in certain hair loss conditions.

Obesity may be more than just a coincidence in certain hair conditions. More research is needed for many of these conditions but I will highlight a few here including the role of obesity in androgenetic alopecia, alopecia areata. dissecting cellulitis and acne keloidalis.

a) Androgenetic Alopecia

In males with androgenetic alopecia, obesity is associated with greater severity of hair loss. Whether this hold true for women is still controversial. A Taiwanese study showed that overweight and obese males had about a five times increased risk for severe forms of hair loss compared to males who were not overweight.

The relationship between obesity and male balding continues to be studied in other areas too. Some investigators have proposed that some male patients with early male balding (before age 25) may in fact have a male equivalent of “PCOS”. These males may be at risk of developing the same complications associated with PCOS, including obesity, metabolic syndrome, insulin resistance, cardiovascular diseases, and infertility. Addressing obesity in males with early balding it generally thought to be important as male patients with early balding are now known to be at increased risk for heart disease later in life.

There may be an important relationship between a hormone called leptin and androgenetic alopecia. Leptin was discovered in 1994 and is an important hormone that tells that body that enough food has been consumed. In obesity, high levels of leptin in the blood are consistently noted and researcher have proposed that ‘leptin resistance’ may be part of the problem in obesity. A 2017 study in the journal Experimental Dermatology showed that higher leptin levels were associated with a risk of developing more severe forms of androgenetic alopecia. This highlights the important relationship between obesity and balding.

b) Alopecia Areata

Obesity may also have a role in alopecia areata in ways that we never appreciated before. A 2020 study from the Cleveland Clinic showed that children with alopecia areata were much more likely to have obesity that children who did not have alopecia areata. Of course, not all children with alopecia areata are obese but this study highlighted the potentially important role of obesity. The same findings were also noted in adults with alopecia areata. In fact, a 2021 study by Conic and colleagues found a nearby 9 fold increased risk of obesity in patients with alopecia areata compared to those without alopecia areeata.

c) Dissecting Cellulitis

In 2018, Lee and colleagues showed that about 65 % of patient with dissecting cellulitis are obese or overweight. This may be contributing in ways that are not completely clear.

d) Acne Keloidalis

Obesity may also be a factor in acne keloidalis, a type of scarring alopecia that affects the back of the scalp. A small study from Brazil identified obesity in 100 % of patents with acne keloidalis. The median BMI was 32.2.

e) Scalp Psoriasis

Studies have shown that obesity increases the risk of developing psoriasis by 2 to 3 fold. In fact several research studies have now proven that obesity is an independent risk factor for the onset and severity of psoriasis.

3. Treatment of Obesity can Cause Hair Loss

Weight loss is one of the common causes of telogen effluvium or “hair shedding.” Patients that start strict diets often develop shedding about 6-8 weeks after starting the diet. Diets that are more restrictive than 1300 calories per day often give hair shedding. In addition, dieting that is associated with more than 10 pounds of weight loss per month are at significantly increased risk of telogen effluvium.

Bariatric surgery is a very common trigger of hair loss nowadays. According to the American Society for Metabolic and Bariatric surgery about 250,000 bariatric procedures are performed in the United States every year. These procedures are associated with high rates of hair loss. Hair loss occurs in about 60 %-75% of patients and may be more common in women than men. Studies point to a variety of factors that trigger hair loss after bariatric surgery, including various mineral and vitamin deficiencies. Hair loss typically starts at month 3-4 and can last 5-6 months.

4. Some Hair Loss Medications Add to the Problem of Weight Gain and May Create Problems for Patients Trying to Lose Weight.

Some mediations used in treating hair loss make it more difficult to lose weight and may even cause weight gain. Finasteride and dutasteride, which as used for treatment of androgenetic alopecia, cause weight gain in a proportion of users. This may be more common in women than men but more studies are needed.

Doxycycline, used for treating scarring alopecia like lichen planopilaris also causes weight gain in some users. The immunnosupressant prednisone is a well known cause of weight gain. Antihistamines used in lichen planopilaris and alopecia areata can cause weight gain in some users.

5. Hair Loss Specialists Need to Learn Skills to Openly Discuss Obesity.

We live in a society which aims not to create any sort of direct confrontation that might embarrass another person. For this reason, people scoot around the topic of obesity. Recent studies teach us that physicians are no different. One study suggested that nearly two-thirds of U.S. physicians say they don’t discuss weight loss with their obese patients for fear of embarrassing them.

Study after study suggest that talking about obesity can help patients make important changes. Hair specialists are not generally specialists in obesity but the first step is simply showing that one cares. Talking about obesity is not easy but experts tell us that the first step is to ask patients for their permission to talk about this topic. Through the simple act of caring for another person, it’s possible for a hair specialist to help a patient with obesity formulate an initial plan to seek help.

References

Conic et al. Comorbidities in pediatric alopecia areataJ Eur Acad Dermatol Venereol. 2020 Dec;34(12):2898-2901.

Conic et al. Prevalence of cardiac and metabolic diseases among patients with alopecia areata. J Eur Acad Dermatol Venereol. 2021 Feb;35(2):e128-e129.

Kelly T, Yang W, Chen CS, Reynolds K, He J. Global burden of obesity in 2005 and projections to 2030. Int J Obes (Lond). 2008;32:1431-7.
Flegal KM, Carroll MD, Kit BK, Ogden CL. Prevalence of obesity and trends in the distribution of body mass index among US adults, 1999-2010. JAMA. 2012;307:491-7.

Katsagridaki G et al. Hair Loss After Laparoscopic Sleeve Gastrectomy. Obes Surg. 2018 Dec;28(12):3929-3934.
Lee et al Dissecting folliculitis (dissecting cellulitis) of the scalp: a 66-patient case series and proposal of classification. J Dtsch Dermatol Ges. 2018 Oct;16(10):1219-1226.

Matsunaga AM et al. High Frequency of Obesity in Acne Keloidalis Nuchae Patients: A Hypothesis from a Brazilian Study. Skin Appendage Disord 2020 Nov;6(6):374-378.

Sanke S et al. A Comparison of the Hormonal Profile of Early Androgenetic Alopecia in Men With the Phenotypic Equivalent of Polycystic Ovarian Syndrome in Women. JAMA Dermatol 2016 Sep 1;152(9):986-91

Sam S et al. Obesity and Polycystic Ovary Syndrome. Obes Manag. 2007 Apr; 3(2): 69–73.Sen O et al. Hair Loss After Sleeve Gastrectomy and Effect of Biotin SupplementsJ Laparoendosc Adv Surg Tech A 2020 Aug 5.

Setty AR, Curhan G, Choi HK. Obesity, waist circumference, weight change, and the risk of psoriasis in women: nurses' health study II. Arch Intern Med.(2007) 167:1670–5. 10.1001/archinte.167.15.1670

Yang et al. Higher body mass index is associated with greater severity of alopecia in men with male-pattern androgenetic alopecia in Taiwan: a cross-sectional study. J Am Acad Dermatol 2014 Feb;70(2):297-302.e1.

Yang et al. Higher plasma leptin is associated with higher risk of androgenetic alopecia in men. Exp Dermatol. 2017 Jun;26(6):524-526.