DHT, or dihydrotestosterone, is an androgen hormone that plays a crucial role in men’s and women’s physical development and health. However, too much of it can lead to hair loss. Learn more about DHT and its role in male pattern baldness below.
Effects of Excess DHT on Men
In men, DHT is one of the androgen hormones that accounts for changes during puberty, including increased muscle mass, deeper voice, and body hair. However, DHT levels can become imbalanced and exist in excess. An enzyme called 5-alpha reductase normally converts testosterone, producing DHT. About 10 percent of testosterone is normally converted to DHT, but other issues can result in the enzyme converting too much testosterone into DHT.
When DHT is produced in excess it binds to androgen receptor sites in cells. Studies show that DHT binds to these androgen receptor sites with greater affinity compared to testosterone. DHT also stays bound to these sites for longer and is more powerful, resulting in imbalances resulting in problems such as DHT.
Excess DHT has most commonly been connected to benign prostatic hyperplasia (an enlarge prostate) and may contribute to prostate cancer. High DHT levels are also known to contribute to androgenic alopecia, better known as male pattern baldness, by gradually shrinking the follicles in the scalp. Hair follicles at the front of the scalp and at the very top have androgen receptors that bind to DHT.
When DHT binds to these follicles, the hair growing phase while extending the resting phase. Over time, older hair will fall out much easier without any new hair to replace it. Shrinking follicles also cause the hair shaft to become thinner after every cycle, eventually leading to soft, light hairs known as vellus hairs.1
How Does the DHT Blocker Finasteride Work?
Finasteride is one of the few FDA-approved medications for preventing hair loss and promoting hair growth. It is a DHT blocker, it blocks DHT by inhibiting the production of DHT by the enzyme 5-alpha reductase (5-AR). Blocking 5-AR prevents the conversion of testosterone into DHT, which regulates the levels of both hormones and can help to prevent male pattern baldness at the source. The medication has been found to reduce DHT levels in the blood by up to 70 percent and in the scalp specifically by up to 60 percent.2
What are the Typical Results When Using Finasteride?
Finasteride has been studied extensively for its effects. A meta-study reviewed 12 studies to determine the safety and effectiveness of finasteride in male pattern baldness both in short-term (less than 12 months) and long-term (greater than 24 months). The total number of subjects from the studies comprised 3,927 men suffering from androgenic alopecia with outcome measures that included hair count, clinical assessment, and self-assessment. The meta-study found that those who had used finasteride showed a statistically significant improvement in scalp hair compared to placebo groups in both short- and long-term studies. Finasteride therapy also resulted in an increase in average hair count compared to placebo groups. Self-assessment and investigator clinical assessments also improved, particularly in the short-term.1
What Types of Hair Loss Do DHT Blockers Treat in Men?
Not all forms of hair loss are created equal, nor do all potential hair loss treatments affect the same areas of the scalp. Finasteride and other DHT blockers are specifically designed for androgenetic alopecia, which is caused by excess DHT.
DHT blockers are best for hair loss at the vertex of the scalp and thinning in frontal scalp and temples resulting in a receding hairline. In a double-blind, placebo-controlled study, researchers aimed to evaluate the efficacy of finasteride in different parts of the scalp. The study lasted one year followed by a one-year open extension. Subjects with male pattern baldness took 1 milligram of finasteride per day, and researchers determined efficacy based on hair count, investigator assessments, self-assessments, and photographic review. Results found that finasteride is effective for hair loss in the vertex and anterior areas of the scalp with efficacy maintaining or even improving through the second year of the study.4
At What Age Can You Start Taking a DHT Blocker?
Considering how important DHT is during puberty and the development of physical male characteristics, finasteride and other DHT blockers should only be used by adult men.
One study aimed to determine the efficacy of finasteride on men age 18 to 60 with male pattern hair loss. The double-blind, randomized study split groups of men age 18 to 41 and age 41 to 60 into groups given a placebo or 1 milligram per day of finasteride. The researchers then evaluated the effectiveness based on clinical photographic reviews of the vertex, anterior, and middle scalp as well as the front and temporal hairlines over the course of 24 months.
While all men showed improvements in hair loss, only the younger group (age 18 to 41) showed reduced hair loss in all areas of the scalp and hairline. Older subjects (age 41 to 60) showed reduced hair loss only in the vertex and anterior regions of the scalp. This suggests that finasteride and other DHT blocker ingredients may be more effective in younger men than in older men.5
What are Some Side Effects of the DHT Blocker Finasteride?
Although most men who use finasteride do not experience any adverse side effects, some men do experience side effects. About 1.5 percent of men in one study experienced an increase in erectile dysfunction and a possible increased risk of other sexual disturbances. However, most men reported a reversal of any symptoms of sexual dysfunction after stopping use of finasteride.1
Other studies also suggest that finasteride may reduce sperm counts in men during treatment. However, this symptom is also known to reverse after cessation of finasteride treatments.6 Some studies have also found that finasteride may cause gynecomastia, an enlargement or swelling of breast tissue in men caused by hormonal imbalances, in a small number of those treated with finasteride for male pattern baldness.7
In another study, a group of 128 men with androgenetic alopecia were prescribed finasteride. The subjects completed questionnaires from the Beck Depression Inventory (BDI) and the Hospital Anxiety and Depression Scale (HADS) prior to the study and two months after the completed treatment. Results showed that finasteride treatment increased symptoms of depression based on increased scores in both the BDI and HADS.8 However, further studies are required to understand the full behavioral effects of finasteride, particularly in higher doses and in those patients more susceptible to depression.
What are Some Natural DHT Blocker Foods and Herbs?
Although finasteride is one of the only FDA-approved DHT blocking treatments for male pattern baldness, there are a variety of natural foods and herbs as well as topical ingredients that possess natural DHT blocking properties. Many of these natural DHT blockers work through similar mechanisms as finasteride: they inhibit 5-alpha reductase to prevent the enzyme from converting testosterone into DHT. Some of the most common natural DHT blockers include:
- Saw palmetto
- Stinging nettle
- Pumpkin seed oil
- Green tea extracts
Some natural DHT blockers that may be used topically include:
- Tea tree oil
- Lavender oil
Finasteride is an effective DHT blocker ingredient that may be the modern male pattern baldness cure, but it may not be for everyone. If you prefer a natural alternative to reduce hair loss, you should also consider natural DHT blocker ingredients that may support healthy hair growth without the potential side effects of finasteride.