Preventing AGA in Men and Women
I'm often asked if one can prevent genetic hair loss. The typical scenario is a patient whose parent or sibling is bald or balding and wants to know if they can reduce their chances of developing a similar pattern of hair loss. Can one prevent balding outright? In the present day, that answer is no. However, there are things that can be done to reduce the magnitude and speed of progression of the hair loss.
Genetic Hair Loss is strongly ... genetic. It's the genes inside the hair follicles that influence how the hair loss will or will not unfold. We'll take a look at factors that can affect genetic hair loss to a slight degree in a moment, but first let's turn our attention to studies of identical twins.
Studies of identical twins are very important in answering questions like "does what I eat affect my rate of balding?" or ,,,, "does being stressed affect how fast I bald?"
Identical twins carry the same genetic profile. By studying the appearance of identical twins at various points throughout their lives, we can get a better sense of how important factors like genetics and the environment actually are. If genes are the "key factor" in how balding progresses then, identical twins should look ‘identical’ in terms of their hair density at various points in their lives. In contrast, if environmental factors like smoking, drinking, stress, weight loss and ultraviolet radiation are important, identical twins might not have the same hair density because their environment is different.
The 1992 Hayakawa Study
Interesting research studies in 1992 showed that genetics is by far the most important factor and the environment only has a minor role. 92 % of identical twins were found to have "no significant" differences in their hair density at later points in their lives. However, 8% of identical twins had a slight difference. Interestingly, no twin had a striking difference! In other words, there was never a situation where one identical twin was bald and another had full hair. These studies support the notion that one’s genetics is by far the most important factor in the balding process - but there is a slight role for how outside 'environmental factors' shape genetic hair loss.
Limiting Genetic Hair Loss: Optimizing Environmental Factors
The Hayakawa studies taught us that there is a bit of room to optimize how fast genetic hair loss occurs. Overall, these factors have a minor role but still have some role. These factors include the following.
1) Be a non smoker.
It's clear that smoking can influence genetic hair loss by speeding up how fast it progresses. An important study examing the relationship between smoking and hair loss was a 2007 study by the Taiwanese group of Dr. Su and Dr Chen. These researchers examined 740 patients between the ages of 40 and 91 over a 2 month period. They found that smokers generally had worse androgenetic alopecia compared to non-smokers. In fact, smokers had nearly a two-fold increased risk of having moderate or severe genetic hair loss compared to non-smokers. In addition, the early development of male balding was more likely in smokers. The exact reasons is not clear but it has been proposed that smoking is damaging to the tiny blood vessels and the there are toxic substances in cigarette smoke that damage the cells in the hair follicles. It's also possible that smoking causes inflammation which speeds up the process of genetic hair loss.
2) Keep a healthy weight.
It does appear that obesity increases one's risk of developing worsening androgenetic alopecia. A 2011 study looked at the risk factors for male balding in policeman in Taiwan. Interestingly, young male policemen who were obese had much higher rates of male balding than thinner policemen. In 2014, researchers from Taiwan explored whether there was a relationship between obesity the severity of male balding. They studied 142 men (average at 31 years) with male balding who were not using hair loss medications. The study showed that men with more severe hair loss tended to be more overweight than men with less severe hair loss. In fact, men who were overweight or obese had an approximately 3.5 fold greater risk for severe hair loss than men with more normal weights. In addition, young overweight or obese men had a nearly 5 fold increased risk of severe hair loss. The exact reasons are unclear. However, obesity leads to altered metabolism, insulin resistance and worsening inflammation that could affect balding.
3) Limit excess triggers that cause shedding (weight loss, stress, some medications).
Individuals with genetic hair loss are well advised to limit triggers of shedding. This is not always easy to do, but shedding can trigger worsening of hair loss in some people. Repeated cycles of shedding speeds up the arrival of genetic hair loss in patients who are genetically predisposed to develop genetic hair loss. In my hair clinic, I use the term AFMPS - or Accelerated Follicular Miniaturization from Prolonged Shedding. It's a phenomenon that happens only in those who are predisposed to develop androgenetic alopecia. It's a phenomenon that is frequently seen but rarely is it fully appreciated.
The concept of AFMPS is very important. It is critically important to limit hair shedding in those predisposed to genetic hair loss. Everything that causes shedding - iron, thyroid issues, dieting, medications, stress, seborrheic dermatitis - must be properly managed.
4) Limit anabolic steroid use.
Anabolic steroids can worsen genetic hair loss in those that are predisposed. These steroids increase the pool of androgens that all act to facilitate miniaturization.
5) Reduce ultraviolet radiation to the scalp.
An interesting study from researchers in Taiwan offers further clues that sunlight just 'might' contribute in some way to male balding. The researchers compared balding patterns in 758 policemen and 740 men in the general polulation. Interestingly, policemen aged 40 to 59 had a two fold increased risk of having male balding. In addition, there was a statistically significant association between male balding and sunlight exposure. More research is needed understand if and how ultraviolet radiation affects the process of male balding. Reference
It's not always possible to prevent genetic hair loss. However, it may be possible to reduce the speed of its progression by limiting hair shedding and limiting toxic (i.e. smoking, obesity, UV radiation) and hormonal effects (i.e. anabolic steroids) on the hair follicle.
Hayakawa K, et al. Intrapair differences of physical aging and longevity in identical twins. Acta Genet Med Gemellol (Roma). 1992.
Su LH and Chen T H-H. Association of Androgenetic Alopecia with Smoking and Its Prevalance Among Asian Men. Archives of Dermatology 2007 143; 1401-1406.
Mosley JG and Gibbs AC. Premature grey hair and hair loss among smokers: a new opportunity for heatlh education? British Medical Journal 1996; 313: 1616.
Severi G et al Androgenetic alopecia in men 40-69 years: prevalence and risk factors.British Journal of Dermatology 2003; 149: 1207-1213
Chao-Chun Y 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; 70; 297-302.
Su LH et al. Androgenetic alopecia in policemen: higher prevalence and different risk factors relative to the general population (KCIS no. 23). Arch Dermatol Res. 2011 Dec;303(10):753-61