“Each person has a unique hair type and texture; the hair that grows out of your scalp is always going to be the true texture of your hair. Even if you go for a straightening treatment, it’ll only affect the bottom half of the hair. So, if you have naturally wavy or curly hair, it will still grow in that way,” explains Cédric, a celebrity stylist and owner of Cédric Salon at Lotte New York Palace Hotel. However, since your hair is aging every day, it’s possible to notice changes (from texture to thickness). By the time you hit your late 30s to early 40s, the products, tips, and styling techniques you used during your 20s may no longer work. While we can’t stop time, there are ways to protect your hair from aging rapidly, and similar to skin care, the key to anti-aging haircare starts with practicing the right habits—the younger, the better. To find out what exactly is happening to our follicles as we get older, we spoke to leading trichologists, celebrity hairstylists, and a dermatologist to understand how hair DNA impacts our hair throughout the years.
What Is Hair DNA?
Hair DNA consists of genetic material used as building blocks for our hair. “Our hair follicle contains nucleic acid DNA, while our hair shaft contains mitochondrial DNA. It provides essential information forming the basis of how our hair grows, contributing to the color, texture, strength, and response to UV damage,” explains Sue Chan, MD, a consultant dermatologist at the Birmingham Skin Centre. It isn’t currently possible to permanently change the building blocks of your hair DNA (e.g., going from straight to curly hair), unless there’s a mutation from a disease like cancer. However, it is possible to break the bonds in the hair which give it its structure, and this is why your hair type can change throughout your life. “There are three types of bonds in the hair: hydrogen, disulfide, and salt,” says Anabel Kingsley, Philip Kingsley brand president and consultant trichologist. “Hydrogen bonds are broken by water, which explains why our hair becomes frizzy in humid weather. Disulfide bonds are broken with chemical processing like perming or chemical straightening, and salt bonds are broken by pH changes.”
How Does Hair Age?
Just like skin, hair DNA damage can accumulate with age. While many people are preoccupied with minimizing the signs of aging on their faces, neck, and hands, they forget to pay attention to their scalp, “which ages at the same rate and encounters daily stress like our skin,” says Dr. Chan. From overly tight hairstyles to washing with water that’s too hot, environmental stressors can slow down nutrients and blood flow to the scalp, which, in turn, disrupts hair growth and affects hair DNA. Several main changes cause hair DNA to age: hormonal, mechanical, and chemical. “When the hair is changed hormonally, the changes come from the follicle and sometimes result in increased oil production and means the hair gets greasier easier. Mechanical changes occur in the hair shaft and are usually caused by heat styling. On the other hand, chemical changes primarily happen when someone changes the color or texture of their hair,” says Gretchen Friese, stylist at Foushee Salon and Spa. While people tend to only focus on their “hair age” once they get their first gray hair (typically in their 30s), Kingsley reminds us that these changes have been happening all along. “As we get older, the cells in our hair follicles that produce melanin or pigment gradually reduce, causing new hair strands to grow unpigmented or white. Gray is not actually a hair pigment in itself—it’s a color that results from a combination of normally pigmented hairs interspersed with white ones and turns from grey to white when all hair pigment cells stop being produced,” she says. As your hair DNA ages, the hair might feel drier and coarser, but it’s not a real texture change. In reality, your sebaceous glands, which are attached to each hair follicle, simply begin to secrete less oil than before as your hair grays. In other words, it’s essential to take care of your scalp with regular treatments and at-home products in order to avoid weakening the natural integrity of your hair DNA.
Which Type of Hair DNA Ages the Quickest?
According to stylists and trichologists, curly, wavy, and coiled textures are the most fragile hair type because the twists create weak points in the hair. When this is combined with daily habits of “heat styling, brushing, and chemical processing, it affects the hair’s condition,” explains Kingsley. These hair types must regularly use intensely hydrating and nourishing ingredients in their routine, like almond and avocado oils, vitamin E, and fatty acids.
Can You Prevent Hair Aging?
The answer is yes and no. Genetics play a big role in how drastically your hair DNA will age. “As we age, our strands gradually get finer in diameter and cannot grow as long as they once could,” Kingsley says. However, the degree of change can be controlled by things like your diet, lifestyle, and general hairstyling habits. Think of it as the same concept as epigenetic skincare, which focuses on how environmental factors can affect the expression of genes. Your hair habits can affect gene behavior and counteract undesirable increases or decreases in activity. In order to help your hair DNA age as healthily—and slowly—as possible, it’s essential to maintain proper scalp care, restore moisture to the hair’s cuticle, limit heat styling and chemical processes like coloring, and manage other environmental stressors.
