Gray hair is a tell-tale sign of aging and stress—or, at least, that is what society believes. This is why the sight of even a single gray hair can be so distressing—we tend to associate it with negative feelings or getting older.

But are age and stress really to blame for going gray? And if so, why do some people get gray hair much earlier in life than others? Here are the scientific secrets behind gray hair.

The cause of gray hair

The biggest misconception about gray hair is that hair “turns” gray, as if a single strand could be both pigmented and gray at the same time. This is not what happens.

A particular strand of hair will retain its pigment throughout its life cycle. However, when a new strand of hair grows in its place, it may be less pigmented than the previous one. The reasoning behind this is rooted in the hair follicles in your scalp.

Over time, your hair follicles lose the cells that produce pigment. Thus, your hair is likely to become less colored over time, eventually growing out gray. You may not notice this right away because of how slow the hair growth and shedding phases are. This is why people tend to notice one or just a few gray hairs at first—because the pigment is determined by each follicle.

Genetics is one of the major influences on how early your follicles may begin to lose pigment, which is why people tend to get gray hair at different ages. However, it’s safe to say that after the age of 35, gray hairs are likely to become more and more common.

What this means is that age is linked to growing gray hair—but only somewhat, since everyone will grow their first gray hair at slightly different ages! Additionally, stress is not a direct cause of gray hair; however, it can be linked to hair loss.

Premature graying

Although gray hair is largely linked to aging follicles, there may be some instances where people experience graying much sooner or much more rapidly than they expect to.

One of these instances may be linked to stress. Chronic stress can be a trigger for a condition called telogen effluvium, in which hair is put into its resting phase prematurely and falls out much earlier en masse. Hair typically begins growing again once this happens, so gray hair may become much more noticeable after the period of hair loss if your follicles have begun to lose pigment.

Other situations can cause premature graying by affecting the follicles themselves. These are usually illnesses or medical conditions that should be treated by a doctor. A deficiency in vitamin B12, thyroid disorders and tumors could be at the root of premature graying.

Vitiligo may also be at fault. In this condition, the body affects cells that contain pigment, called melanocytes—destroying them or inhibiting their growth. Experts are not sure what causes vitiligo, but it can affect numerous parts of your body, including patches of hair, your skin and your mouth.

Finally, smoking has been linked to premature graying, as well.

Is gray hair reversible?

When you discover your first gray hair, you may panic and immediately search for ways to reverse the natural graying process. In some cases, this is impossible—it is merely a side effect of aging. However, you may be able to reverse prematurely graying hair, delay it or simply cover it up to fit your personal style.

• Stop smoking: If you’re a smoker, quitting may help prolong the life of your melanocytes and retain your hair’s natural color for longer. Plus, smoking is bad for your health in many other ways, so you’ll be doing both your hair and body a favor!
• Get more B vitamins: Vitamin B12 deficiency has been linked to a reduction in melanin production, which could affect your hair color. Try to add more vitamin B-loaded foods to your diet, such as beef, chicken, yogurt and eggs, or take vitamin B supplements.
• Relieve stress: Because stress has been linked to poor hair health and potential conditions like telogen effluvium, taking time for stress relief may help your hair stay on your head for longer, delaying the appearance of gray hair.
• Natural remedies: There are many natural remedies that may help delay the appearance of gray hair or reverse premature graying, including Fo-Ti root, Indian gooseberry and curry leaves.
• Styling: If gray hairs have appeared and are there to stay, you can try to style your hair to hide them by doing twists and using hair accessories. If your roots or all your strands are gray, you may also choose to dye your hair back to its original color—just make sure to take care of it to prolong its health!

Gray hair isn’t something to be ashamed of. It’s a natural part of life, and many people choose to rock their gray hair in its natural state! Just remember; whether you choose to embrace your gray hair or find ways to reverse or mask it, pay close attention to the health of your hair first and foremost.