In short

  • First of all, not all men go bald, and secondly, genes play a significant role in determining hair growth or loss in different parts of the body due to the presence of androgen receptors.
  • Different androgens bind to the receptors and either activate or deactivate the genes that regulate hair growth.
  • However, it is the imbalance of two androgens, testosterone and dihydrotestosterone (DHT) that cause additional discrepancies or paradoxes whereby you can have loads of back hair and a bald head.

First of all, not all men go bald, and secondly, genes play a significant role in determining hair growth or loss in different parts of the body due to the presence of androgen receptors. Different androgens bind to the receptors and either activate or deactivate the genes that regulate hair growth. However, it is the imbalance of two androgens, testosterone and dihydrotestosterone (DHT) that cause additional discrepancies or paradoxes whereby you can have loads of back hair and a bald head. DHT is five times more potent than testosterone, but both are responsible for the typical male sex characteristics and function differently.

During adolescence in males, testosterone causes enlargement of the penis, production of sperm, increased muscle development, deepening of the voice, and sex drive. This is considered an anabolic process, whereas DHT is responsible for the androgenic properties of hair growth, beard growth, and acne. Later in life, excess DHT can cause male pattern baldness and prostate enlargement.

What is DHT?

DHT (dihydrotestosterone) is formed from the enzymatic action of 5 alpha-reductase on testosterone and is hence derived from testosterone. Male pattern baldness is genetically determined and thus explains why some men do not respond to the elevated DHT levels and keep a full head of hair. The effects of DHT on genetically susceptible men leads to scalp hair follicle miniaturisation and hair loss. Inhibitors of the conversion of testosterone to DHT are used to treat baldness and help regrow hair. An excessive amount of DHT can block other essential nutrients from reaching the hair follicles resulting in the degradation of hair, shrinking the hair follicles and thus eventually leading to baldness as the hair stops growing.

How to reduce DHT?

Generally practising a general healthier lifestyle (regular exercise, stopping smoking, reducing stress levels, relaxation) is sufficient in reducing DHT levels in the body. Diet is a significant contributor in DHT levels as some foods have natural DHT blocking properties. Vegetables rich in zinc, containing phytosterol, stop the production of DHT and reduce areas in which DHT can reach hair follicles. Zinc-rich vegetables include spinach, white mushroom and kale, to name a few. Other foods such as tomatoes, watermelons, carrots and mangoes also have natural DHT blocking properties and berries, liver, legumes and fish oil are rich in Biotin (Vitamin B7) which have been linked to healthier hair and nails. 

What if DHT blocker?

If you spend enough time scouring the internet for hair loss treatments, you’ll come across products called DHT blockers (usually in the form of shampoos and conditioners). But what are they and do they do what they claim to do? DHT-blockers give buyers the perception that this increases the amount of DHT to their scalps and hence helps increase their hair growth. Sadly, this is not the case. DHT-blockers are an add on to your daily hair care routine that can aid in slowing down and preventing further hair loss. 

What causes DHT to increase?

The amount of DHT in the body is very closely linked to testosterone (because it is made from testosterone). As your testosterone levels rise, so do your DHT levels. The production of hormones in the pituitary gland is quite complex, with multiple feedback loops at play. However, the science is simple; if you have excess testosterone levels, your DHT levels will closely follow.

Sadly, as much as I know you don’t want to hear this, there is no magical hair loss potion that can restore your hair growth. If you have found products making such claims, we recommend not to waste your money. Scientists have not found a way to stop male-patterned baldness but have found ways to slow down the process with treatments such as Propecia and the generic Finasteride. These are the only licensed prescription treatments in the UK, and you can request them through our online doctor’s service. The medical questionnaire will be reviewed by one of our GPs who can review your answers and prescribe them for you if appropriate. 

Sources

References

2 sources were selected to match the subject of this article. Link destinations were checked twice when added. This does not mean every statement has been individually source-mapped or clinically approved.

  1. Propecia 1 mg Film-Coated Tablets — Summary of Product Characteristics

    electronic medicines compendium (emc) · HTML · SmPC · Last updated on emc 14 July 2026 · Link destination checked 5 September 2026

  2. Dihydrotestosterone

    South Tees Hospitals NHS Foundation Trust · HTML · NHS laboratory medicine explainer · Link destination checked 5 September 2026

Reference links open the cited source pages. If you spot something out of date, tell our content team.

Who wrote this

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Authored by

Ian Coakley, Content Writer

Content Writer

Ian is Simple Online Pharmacy’s Content Writer; he joined the team in 2021. He has had a varied career path, starting as a science communicator and freelance editor and writer. While Ian has been published in some independent outfits, Simple Online Pharmacy marks his first foray into writing for a corporate entity.

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Medically reviewed by

Karim Nassar, Co-Founder, Pharmacist & Author

Karim Nassar

Co-Founder, Pharmacist & Author

Karim is a registered pharmacist with the General Pharmaceutical Council (GPhC) and was a founding member of Simple Online Healthcare in 2015. With a Master of Pharmacy degree from Strathclyde University, Karim brings a strong foundation in pharmaceutical care and a passion for leveraging digital solutions to improve patient access to healthcare.

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