5 Most Common Causes Of Hair Loss In Men

Two-thirds of men in the U.S. experience hair loss by the age of 35. Here, two hair restoration experts break down the most common causes and treatment options.
Written by Samantha Stone
Is this article helpful?6 min read
5 Most Common Causes Of Hair Loss In MenNqobile Vundla/Unsplash

Men are no strangers to hair loss. According to the American Hair Loss Association, two-thirds of men in the United States experience hair loss by the age of 35. By the age of 50, approximately 85 percent of American men report noticeable hair thinning. While receding hairlines and bald spots can be attributed to genetics, there are other types of hair loss and thinning that occur as a result of diet, medical conditions, medications, stress, and more. Here, a guide to the five most common causes of hair loss in men and how to treat them.

1. Genetics

Genetics (read: family history) is the overwhelming culprit of balding among men. Male pattern baldness (MPB) accounts for more than 95 percent of hair loss among men in the U.S. Medically known as androgenetic alopecia, male pattern baldness is characterized by a receding hairline and thinning around the crown of the head. The American Hair Loss Association reports some 25 percent of men start to see the effect of MPB as young as age 21.

Hereditary hair loss is usually caused by hormonal changes. “Hormonal imbalances play a big role in both male and female pattern hair loss,” says Benjamin Paul, MD, a double board certified facial plastic and reconstructive surgeon in NYC. “Genetic hair loss often involves a sensitivity to androgens, hence the [term] ‘androgenic alopecia.’”

As Dr. Paul explains, when the hair follicle is sensitive to androgens — particularly dihydrotestosterone (DHT) — the hair shaft miniaturizes and becomes smaller in diameter. “Over time, the hair may not grow at all,” he says, adding some non-surgical hair restoration solutions directly address this hormonal imbalance. “There are many treatments, such as Propecia and saw palmetto, that directly lower DHT and improve hair growth and longevity,” he shares.

Minoxidil (a.k.a. Rogaine) is a topical medication applied directly to the scalp to stimulate hair growth. Platelet-rich plasma (PRP) injections for hair loss are another minimally invasive treatment option gaining popularity. During the procedure, the doctor will draw blood (usually from the arm) and separate the platelets using a centrifuge to concentrate the growth factors. Once injected into your scalp, PRP brings increased blood flow to the hair follicles, which stimulates new growth and lengthens the anagen (i.e. active) phase of the hair cycle to promote growth.

Men looking for a more permanent solution may consider surgical hair transplants. The surgery involves harvesting hair follicles from a donor site (usually the back of the head) and transplanting them to a bald or thinning area. In a follicular unit extraction (FUE), individual hairs are removed, while a follicular unit transplantation (FUT) involves harvesting a strip of hair. While the process is highly effective, it requires patience. It can take 12 to 18 months to see full results.

2. Diet & Nutrition

While diet does not usually play as big a role in male hair loss as it does for women, nutritional deficiencies can lead to unintended thinning and shedding. This is particularly true when men fail to meet the required dietary allowances (RDA) of vitamins and minerals. Key contributors to hair growth include iron, zinc, vitamin B, and protein, which are naturally found in many animal products.

“Most of us get enough biotin and other b-complex from our diets,” says Gary Linkov, MD, a double board certified facial plastic and reconstructive surgeon in NYC. “But, if not, then supplementation can help.” While vitamins alone won’t restore your hairline, they are important for overall health. “Usually this is not the most effective way to maintain hair health,” he cautions. “But it does have a really good safety profile, so sometimes patients opt to take hair supplements instead of other treatments.”

Be sure to consult with your provider before introducing any new vitamins or supplements to your regimen. Once you get the greenlight, remember that consistency is key. “As with most hair treatments, at least six months of consistent use is recommended before assessing for efficacy,” Dr. Linkov says.

3. Medical Conditions

For men and women alike, there are an array of medical conditions that can cause hair loss. While the thinning or balding is not always permanent, hair restoration options will depend on the underlying medical condition being treated. Dr. Linkov lays out some common medical conditions linked to hair loss below:

Alopecia Areata

The most common condition to cause inflammation-induced hair loss, alopecia areata is characterized by well-demarcated patches of hair loss. It can progress to complete loss of hair from the scalp (alopecia totalis) or from the whole body (alopecia universalis), in severe cases. No treatment is curative, but immunosuppressive therapies are mostly (like corticosteroids) can provide relief. More recently, Janus kinase (JAK) inhibitors have been introduced into the management of alopecia areata.

Hashimoto's Thyroiditis

The leading cause of hypothyroidism, Hasimoto’s thyroiditis occurs when the immune system attacks the thyroid gland, which produces hormones regulating many of the body's activities. If the condition remains untreated, hair loss may result. Additionally, a side effect of thyroid replacement therapy with levothyroxine may lead to prolonged or excessive hair loss.

Graves’ Disease

Another thyroid disorder, Graves’ disease causes antibodies to bind to the surface of thyroid cells leading to the overproduction of thyroid hormones. Hyperthyroidism can affect the production of new hair on the scalp and sometimes on the body. The imbalance of hormones forces hair follicles to enter the resting phase of the hair cycle prematurely.


A chronic autoimmune disease that affects many different systems, hair loss can occur when antibodies created by the body attack the hair follicles, causing the hair to fall out. Hair may grow back on its own during remission periods, but, if scarring occurs in affected follicles, the loss is likely permanent.

4. Medication

There are a variety of medications that can cause hair shedding or exacerbate existing hair loss conditions. Some common drugs to blame include cholesterol-lowering medications, anticoagulants (found in blood thinners), blood pressure medication, steroids, and acne treatments.

Medication can stimulate hair shedding by interfering with the hair growth cycle — usually in the telogen (resting) and anagen (growing) phases.

  • Telogen Effluvium: The more common type occurs when the drug causes the hair to enter the telogen phase. This leads to premature shedding over the course of a few months.
  • Anagen Effluvium: A side effect of treatments like chemotherapy, this type of hair loss occurs much quicker (days to weeks) and is more severe than telogen effluvium.

“Medications may decrease mitotic activity in rapidly dividing hair matrix cells (anagen effluvium) or put the follicles into a premature rest (telogen effluvium),” Dr. Linkov explains. “In anagen effluvium, hair loss usually occurs within days to weeks of taking the medication. In telogen effluvium, hair loss may begin several months after starting treatment.”

5. Stress

Intense emotional or physical stress — whether it be from the pandemic, work, or rapid weight loss — can not only impact mental health but also physical well-being. Regardless of the trigger, stress can induce shedding or exacerbate hair loss. On average, people shed 100 to 150 strands a day. If you are experiencing high levels of stress and excessive shedding of more than 150 strands a day, be sure to consult with your doctor.

The Takeaway

While men most commonly experience hair loss and balding as a result of genetic predisposition, there are other causes of both temporary and permanent shedding. Understanding the root cause of hair loss will ensure patients receive the best treatment for their condition.

Was this helpful?
SAMANTHA STONEis a contributing writer for AEDIT.

Related Procedures



‘Try on’ aesthetic procedures and instantly visualize possible results with AEDIT and our patented 3D aesthetic simulator.

App QR Code