Did you know that by the age of 50, approximately 50% of men and 40% of women experience noticeable hair loss? In India alone, around 63% of men between 30 and 50 suffer from male pattern baldness. Meanwhile, premature greying affects 27% of young adults.
I am sure, if not you, then someone in your close friends and family might be experiencing this as well.
The question is, what is the reason behind these hair issues like hair greying, baldness, hairfall, etc?
We often look for answers by switching our shampoos, treatments, and home remedies, but what if I tell you the answer to this might be in your genes?
Sounds like another conspiracy theory, right.
However, you are wrong because research shows that hair fall and greying are not just about ageing and switching between hair products, but they are a reflection of how our DNA interacts with daily habits, environmental exposures, and internal stress signals.
In this article, we will discuss how genetics plays a role in hair fall and early hair greying, and how factors like stress, lifestyle, and even hair care products can damage DNA and thereby disrupt the blueprint of healthy hair.
And keep in mind, we are not talking about baldness or baldness genetics! This is all about hair loss and hair greying only!
Related article: Is Your Skincare Routine Silently Damaging Your DNA?
Key Topics:
Genetics of hair loss & greying
Hair loss and hair greying are influenced by a network of genes that control everything from hair length to pigmentation.
Scientists have discovered that there are specific genes that decide how long your hair grows before it falls out, while others control how sensitive your hair is to hormones like DHT (dihydrotestosterone), which can shrink hair follicles and is a key driver of baldness.
For instance, genes ike WNT10A and FGF5 regulate the hair cycle, while the androgen receptor (AR) gene determines how sensitive follicles are to hormones like DHT.
Similarly, when it comes to hair greying, it’s all about melanin. Melanin is a pigment that gives hair its colour. Genes such as IRF4, KIF1A, and NSMCE1 influence the protection and maintenance of melanin.
If there is any disturbance in the regulation of these genes or as certain genes lose their efficiency with age, your hair gradually turns thin, you experience hair fall, and your hair may turn white or grey.
The shocking part here is that although our DNA has set a stage and time for when these events are to take place as we age, everyday factors like stress, lifestyle and the chemicals we use as hair care products can accelerate these events by disturbing the genetic balance.
Environmental triggers and daily habits
A wide range of environmental and lifestyle factors like pollution, poor diet, lack of sleep, stress and even smoking can weaken hair quality. These factors disturb the normal functioning of various hormones, proteins and genes, which can result in oxidative stress and lead to DNA damage in hair follicles.
Pollution
Our hair are unknowingly and unwillingly exposed to pollution through air, water, food, temperature, humidity, UV rays, electromagnetic radiation and noise, a recent clinical study published in brazilian journal of hair health found that these pollutants can alter cellular functions and genetic expression leading to epigenetic changes through the generation of reactive oxygen species (ROS) that accelerate the hair loss.
Related article: How does Air Pollution Affect our Genetics? Peer-Reviewed Studies Suggest
Stress
Stress can be a major contributor to hair loss and grey hair when our body is under chronic stress, a hormone named cortisol is elevated. This hormone can activate certain oxidative stress pathways and disrupt the normal regulation of stem cells in the hair follicle.
A study published in the Harvard Stem Cell Institute explored how chronic stress disrupts hair growth at the DNA level. The study reveals that the stress hormone cortisol maintains the hair follicle stem cells in a resting phase, thereby preventing them from regenerating new hair.
Normally, what happens is, the dermal cells release a molecule called Gas9 to activate these stem cells, but stress hormones block this signal. As a result, follicles fail to enter the growth phase, hair starts shedding without replacement, and stem cells become more vulnerable to DNA damage.
Sleep cycle
When we sleep, our body repairs and restores at the cellular level.
While we are in deep sleep, cells activate DNA repair pathways, clear oxidative stress, and reset circadian genes. When our sleep cycle is disturbed, it can lead to the generation of oxidative stress in our body that can interfere with the DNA repair mechanisms, allowing DNA damage to accumulate in hair follicle cells.
Animal studies further confirm that when the circadian rhythm is disrupted, it in turn impairs hair cycle regulation. Hair follicles have their own clock genes like BMAL1 and CLOCK; these genes play a key role in driving the transition from the growth phase to the resting phase.
When this system is disturbed by irregular sleep, the normal timing of growth and rest phases is also disrupted, therefore weakening hair regeneration.
Harmful chemicals and hair care products
Modern hair care habits like colouring our hair or going for harsh straightening and keratin treatments can often expose our follicles to harsh chemicals. These chemicals can be very harmful to our DNA.
Studies show hair dyes contain aromatic amines like p-phenylenediamine (ppd), which can form DNA adducts. Similarly, straightening products that contain formaldehyde or thioglycolates can produce reactive oxygen species, resulting in DNA strand breaks and oxidative stress in follicle cells.
Even the heat from straighteners and dryers amplifies this oxidative stress and weakens the stem cells vital for hair renewal.
Not only do some shampoos and conditioners contain endocrine-disrupting chemicals such as parabens or phthalates, but exposure to these chemicals can trigger epigenetic changes.
All of these assaults can, over time, disrupt the DNA stability in hair follicles, resulting in hair loss and premature hair greying.
Related article: Vaping vs Smoking: Is Your DNA Safer with E-Cigarettes?
Wrapping up:
Hair issues are often seen as cosmetic problems, but they can be deeply regulated by our DNA and genes.
While DNA sets the baseline for such events, environmental and other factors can disrupt this and result in premature hair loss and hair greying.
The important takeaway from this article is that while we take care of ourselves externally, we often tend to forget what happens internally in our body, and that basically plays a very important role, so it’s high time now that we start taking care of our body at the cellular and genetic level as well.
Works Cited
Geyfman, Mikhail, and Bogi Andersen. “Clock Genes, Hair Growth and Aging.” Aging, vol. 2, no. 3, 18 Mar. 2010, pp. 122–128, https://doi.org/10.18632/aging.100130. Accessed 25 Nov. 2019.
“How Chronic Stress Leads to Hair Loss.” Harvard.edu, 2021, www.hsci.harvard.edu/news/how-chronic-stress-leads-to-hair-loss.
Maiti, Swati, et al. “Hair Dye–DNA Interaction: Plausible Cause of Mutation.” Cosmetics, vol. 2, no. 4, 25 Sept. 2015, pp. 313–321, https://doi.org/10.3390/cosmetics2040313. Accessed 20 Nov. 2020.
Rajput, Rajendrasingh. “Hair Loss due to Pollution, Micro Metabolic Dysfunction, Epigenetics and Role of Nutrients.” Brazilian Journal of Hair Health, vol. 1, no. 1, 24 Sept. 2024, p. bjhh16, https://doi.org/10.62742/2965-7911.2024.1.bjhh16. Accessed 24 Nov. 2024.
