Why Your Hair Gets Thinner With Age and What to Do About It

It's normal to find some hairs in your brush or on the bathroom sink every day. But if that number seems to be ramping up and you notice your hair is looking thinner than it used to, aging or related factors could be to blame.

"Most people experience some hair loss during the aging process. Hair thinning can also occur along with changes in hair texture or color," says Rohit Kakar, MD, owner and director of Orchard Lake Dermatology & Cosmetics in Orchard Lake, Michigan.

As we get older, the number of hair follicles in their growth phase decreases, causing your mane to become less dense. Individual hair strands also start to shrink in diameter, creating the appearance of thinner hair.

These changes are normal and can affect anyone. For people assigned male at birth (AMAB), the changes often take the form of a receding hairline (and/or a growing bald patch at the top of the vertex, or crown, of the scalp), while people assigned female at birth may notice the part in their hair slowly gets wider, according to the Mayo Clinic.

In some cases, factors related to the aging process (or factors that become more likely with age) may worsen hair thinning or make it more noticeable, says Jeffrey Hsu, MD, co-founder and co-director of Oak Dermatology in Chicago.

Here are some of the most common culprits and what you can do about thinning hair.

Everyone's strands tend to get a little sparser as the years go by. But if hair loss or baldness runs in your family, you may be more likely to be affected, according to the American Academy of Dermatology (AAD).

You might notice the changes earlier in life, too, because hereditary hair loss can start in your teens or 20s.

Changing hormone levels that occur during perimenopause and menopause can cause hair to become thinner.

"When levels of the hormones estrogen and progesterone decrease, levels of androgen hormones will increase relatively," explains Dr. Hsu. This change can trigger hair loss.

It's common for prolonged tension or anxiety to take a toll on your body — locks included.

"When the mind or body is stressed, levels of the hormone cortisol increase, which begins to negatively affect our skin and hair," Dr. Hsu says.

Stress can happen for a variety of reasons, of course. But these days, Dr. Hsu notices that it often stems from COVID-19.

"Most recently, we've seen a lot of hair loss after a patient has recovered from COVID," he says. "Post-COVID hair loss is very similar to someone experiencing hair loss while in a stressed state or having had psychological trauma."

Hair loss is a common side effect of many medications, including those used to treat cancer, arthritis, depression, heart problems, gout and high blood pressure, according to the Mayo Clinic.

And these health problems tend to become more common with age.

Both over- and underactive thyroids can cause hair to thin or fall out, notes the Cleveland Clinic.

The good news: The problem typically clears up after starting medication to balance thyroid hormone levels.

Our hair is made mostly of protein, and over time, not getting enough protein in your diet can have a negative effect.

"As one ages, appetite and taste can decrease," Dr. Kakar says.

That can potentially cause a person to eat less and take in fewer nutrients, which can increase the chance for nutritional deficiencies that affect the hair, he explains.

Thinning hair can often be treated. The key is figuring out whether your strands are simply getting thinner due to age or if there's an underlying problem that needs to be addressed, say Drs. Kakar and Hsu. Here's how to do just that.

Make an appointment if you notice your hair is starting to look thinner than usual, is falling out in clumps or if you're starting to notice bald spots.

"We have the tools to determine the type of hair loss," Dr. Hsu says. "Different hair loss warrants different treatments, so it is important to determine the root cause."

Thinning hair caused by a thyroid disorder, for instance, can be addressed by starting thyroid medication. If hair loss is related to chemotherapy, on the other hand, using a special cooling cap during treatment may help minimize the problem, per the Mayo Clinic.

Be gentle with your hair to avoid causing breakage or further damage that can cause it to look even thinner. Try to wash your hair every other day or a few times a week rather than daily, avoid over-brushing your hair and try to minimize your use of heat tools like curling wands or blow dryers, Dr. Kakar says.

Consider your current color routine, too: "If you're dyeing your hair, it's best to have this done in-salon by a stylist who utilizes dyes or systems that are gentler on the hair and can help protect it, such as the Olaplex system," he adds.

Make sure you're getting enough calories overall and eat a variety of wholesome, nutrient-dense foods. Focus on protein and minerals like biotin, zinc and magnesium in particular, Dr. Hsu recommends.

"Hair is made up of a chain of proteins, so consuming enough will minimize the risk of nutrient deficits that can weaken hair," he says.

If you're considering a supplement, look for one specifically targeted toward addressing hair loss. "I personally recommend Nutrafol to all of my patients," Dr. Hsu says. "It's all-natural but it has been formulated to target certain hair-thinning causes."

Thickening shampoos, conditioners and sprays are inexpensive, easy to use, and can help make your hair look fuller, especially when used regularly, Dr. Kakar says. Try OGX Thick & Full Biotin & Collagen Shampoo or Kristin Ess Hair Instant Lift Thickening Spray.

"There are a variety of over-the-counter products for age-related hair loss, including Rogaine and LED light therapy treatments like HairMax or TheroDome," Dr. Kakar says. (But beware, the light therapy treatments are pricey.)

You'll reap the biggest benefits by starting treatments sooner rather than later, but be patient. It can take several months of regular use to notice a change, per the Mayo Clinic.

Oral medications like finasteride can help slow hair loss in people AMAB, Dr. Kakar notes, but it can take a few months to kick in. It also has potential adverse side effects ranging from problems with sexual organs to an increased risk of high-grade prostate cancer, according to MedlinePlus.

Platelet-rich plasma injections, which can be performed in-office, are another option that can be helpful for certain patients. The treatment involves drawing a patient's blood, combining the blood plasma with a high concentration of platelets to promote clotting and reinjecting it into the scalp.