What are the causes of hair loss—and how can you stop it?

Learn about the contributors to hair loss and some of the treatments available to ease it.

male beauty

Updated on January 16, 2024.

It's common and completely natural to lose as many as 100 hairs per day. But if you find yourself looking at the hairs in your shower drain and wondering if there’s a cure for baldness, read on for key facts and tips on how to help prevent your hair from thinning too much.

Get to the root of the issue

A certain amount of hair thinning is a natural part of the aging process. But if you have sudden or patchy hair loss, an appointment with a healthcare provider (HCP) is in order. Sudden or patchy hair loss may be a sign of an underlying disease or condition. For example, skin conditions such as vitiligo, autoimmune disorders such as Addison's disease or alopecia areata, and certain thyroid conditions all can cause sudden or uneven hair loss. Talking to an HCP may lead to treatment that can help with the underlying conditon and the accompanying hair loss.

Food for thought

Your diet can also be a contributor to hair loss. For example, certain dietary and nutritional deficiencies may contribute to hair loss. If your thinning hair is accompanied by thin and fragile fingernails, ask your HCP about getting a blood test for iron-deficiency anemia. Some people, such as those who eat a vegetarian or vegan diet, may not be getting enough iron-rich foods in their diet. 

Additionally, a diet rich in omega-3 fatty acids, vitamin B12, and biotin may play a role in the condition of your hair. These nutrients aren't a cure for baldness, but they may help preserve the shine, strength, and integrity of your hair. Cold-water fish, such as salmon, trouth, and herring, are good sources of these nutrients.

Some studies have shown that green tea may have a positive effect on inherited hair loss. Although the evidence that green tea can prevent hair loss is not strong, drinking the antioxidant-rich tea is a valuable and healthy addition to any diet.

Review your medications

Certain medications, such as those administered during chemotherapy, can cause hair loss. But several more common medications can contribute, too.

For example, certain cholesterol reducers, steroids, high blood pressure medications, and oral contraceptives can cause hair loss. Hormone replacement therapies that contain methyltestosterone may also accelerate hair loss and could exacerbate thinning hair problems in postmenopausal women.

If you think your meds may be to blame, talk with your HCP about alternatives.

For most, it's in the genes

For men who experience excessively thinning hair or excessive hair loss for which there is no known underlying medical reason, the cause may have to do with genetics. In fact, most hair loss in men is inherited: It can come from either or both parents.

One significant contributor to male pattern hair loss seems to be the enzyme 5 alpha-reductase (5-AR), which converts testosterone into dihydrotestosterone (DHT). DHT shrinks the hair follicles in men with a genetic predisposition. Over time, the smaller follicles produce shorter and thinner hair.

What not to blame

As you are working down your list of possible explanations, here are some items to cross off: Chemicals, such as those used to color, perm, or bleach hair or those used to chlorinate swimming pools, do not cause hair to fall out at the follicle or cause permanent hair loss. But harsh chemicals can cause hair to become very fragile and susceptible to breakage, so limiting your exposure to them may help protect the integrity of your hair.

Treating hereditary hair loss

One of the most popular hair loss treatments for men is minoxidil. This topical medication inhibits the enzyme 5-AR and has proven to be effective in treating hair loss in men. But there are some drawbacks to minoxidil.

Consistent use is required to maintain hair growth and results may take up to four months to appear. It also works best for hair growth on the crown of the head, not the frontal hairline or receding hairlines. Once treatment is stopped, hair loss typically returns. Local side effects may include dryness, itching, and redness of the scalp, so talk to your HCP about whether the potential benefits outweigh the downsides and what works best for you.

Another possible treatment for hereditary hair loss in men is the oral medication finasteride. Like minoxidil, this medication inhibits 5-AR. Speak with your HCP about the possible risks and benefits of this medication. A small number of men taking this medication have reported sexual side effects, such as decreased libido.

The future is bright

Hair loss research continues at a rapid pace. Researchers have been successful in regrowing hair on bald mice through the implantation of stem cells. They one day may be able to implant such cells into humans to activate the hair follicles to grow more hair.

But until a permanent cure for baldness is available, your best bet for maintaining a full head of hair is to seek treatment at the first sign of thinning. This will increase your chances of minimizing hair loss.

As an alternative, consider changing your mindset and your conception of what you must look like. For many people, embracing a bald look can be satisfying and even empowering.

Article sources open article sources

American Academy of Dermatology Association. What Is Male Pattern Hair Loss, And Can It Be Treated? Last updated: December 13, 2022.
Mayo Clinic. Hair loss: Overview. March 26, 2022.

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