Androgenetic alopecia (AGA or male pattern hair loss) is a problem that will affect most men at some point in their lives (1). By the age of 50 about 50% of men will suffer from some degree of hair loss, which rises to well over 90% in old age.
DHT (short for dihydrotestosterone) is the male hormone believed to be responsible for the gradual process of hair follicle miniaturization and eventual baldness (2). Like everywhere else in the body, DHT exerts its actions on hair follicles via the androgen receptor (AR). Individuals who suffer from androgen insensitivity syndrome and lack a functional AR do not go bald (3). Androgen receptors are 30% more abundant in the front hair follicles of men with AGA compared to the occipital hair follicles in the back of the head which never miniaturize. Also, the enzymes that synthesize DHT (discussed below) are found in 60% greater quantities in the frontal follicles of these men compared to occipital ones (4).
There is a vast and daunting market of products and purported solutions for removing DHT from your scalp and reversing hair loss. In this article we will cut through the confusion and misinformation to give you the simplest, science-backed ways for achieving this.
DHT Blocking Shampoos
Intuitively, a shampoo seems like the most straightforward way to block DHT in the scalp. As obvious a solution as this might see, the reality is there is no shampoo that’s been FDA-approved specifically for this job. The problem is two-fold: first, there is the limited time during which any shampoo is left on the scalp (allowing absorption to the follicle), and secondly a lack of proven compounds that could go into such a shampoo.
Arguably the closest we have to a DHT-blocking shampoo are ketoconazole-based shampoos (5). These are usually sold under the brand name Nizoral, though there are countless generic versions for a fraction of the price.
Though sold primarily as an anti-dandruff shampoo, research has found that regular use of a ketoconazole shampoo gives hair growth comparable to that obtained with minoxidil (6). There is still no consensus on the mechanism through which ketoconazole achieves this effect, but it is widely thought to be down to its mild anti-androgenic properties, including disruption of the DHT pathway (7). This is at least partly mediated through ketoconazole’s blocking of testosterone, the precursor hormone to DHT (8).
The best way to use such a shampoo would be to apply it at the start of your shower, and meticulously rub it in so it is absorbed into the scalp. Allow it to absorb while cleaning the rest of your body, and rinse it off at the very end, at which point you can use your standard shampoo if you wish. Aim for a minimum 5-minute application.
It is worth repeating that this shampoo is sold as anti-dandruff medication and is meant to be used for a limited period of time, so it is best to consult with your doctor prior to starting long-term treatment for hair loss.
Blocking DHT Systemically
Removing and blocking DHT on the source is the obvious first step but bear in mind that most DHT is not produced at the scalp (9). Instead, it is synthesized from testosterone in other tissues in the body – notably the liver – before entering circulation and eventually reaching the scalp. Lowering systemic DHT is therefore a guaranteed way of dramatically reducing its levels in the scalp.
The most straightforward way of achieving this is through an oral 5-alpha-reductase (5αr) inhibitor. As the name suggests, these medications inhibit the 5αr enzyme which converts testosterone to DHT. Without a functioning enzyme, DHT levels in the blood plummet, which is quickly reflected in the scalp.
The most widely used 5αr inhibitor for baldness is finasteride, which was FDA-approved for this purpose more than 20 years ago (10). Aside from reducing serum (blood) DHT levels in excess of 70%, the standard 1mg daily finasteride dosage has been shown to decrease scalp skin DHT levels by up to 64% (11). It is worth noting that a dosage one fifth as strong, namely 0.2mg daily, is still sufficient to decrease scalp DHT levels by 56%. And given the strong nature of this medication and the potential for side effects, the lower the dosage the better.
Another 5αr inhibitor prescribed off-label for baldness is dutasteride, which is even more potent at blocking 5αr compared to finasteride. A 2.5mg daily dosage of dutasteride has been found to decrease scalp DHT levels by 79%, dropping to 51% for the 05.mg dosage (12). Predictably, this dutasteride-induced reduction in scalp DHT was found to inversely correlate with hair counts. In other words the lower a man’s scalp DHT levels, the more hairs he tended to regrow.
Both finasteride and dutasteride are prescription-only medications and should be commenced after consultation with a dermatologist or other qualified health professional.
Thankfully, for those who wish to avoid the pharmacological route there are a number of plant-based treatments known to block DHT. By far the most popular of these is saw palmetto (serenoa repens), which blocks the 5αr enzyme and decreases DHT’s ability to bind to the androgen receptors in the hair follicles. Direct experimental data on saw palmetto’s effects on scalp DHT levels are lacking (13). However, a well-designed randomized study that compared its efficacy to finasteride over a two-year period found it produced regrowth in 38% of patients (vs finasteride’s 68%) and halter hair loss for 90% of men (similar to finasteride). Saw palmetto’s slightly lower efficacy is counterbalanced by its very low incidence of side-effects compared to finasteride or dutasteride.
Diet and Supplementation
Aside from saw palmetto, a number of other plant substances are thought to block DHT to various degrees, and many of these can be incorporated into one’s diet. These include green tea, stinging nettle and pumpkin seeds. With regards to pumpkin seeds in particular, an influential 2014 paper found that 400mg of pumpkin seed oil daily increased hair counts by up to 40% when taken orally (14). Future studies to corroborate these preliminary results are urgently needed.
Given the popularity of finasteride and other 5αr inhibitors it is understandable that most men will place emphasis on blocking the production of DHT in the first place. But the other, generally overlooked side of the coin concerns the metabolism of DHT: in other words how fast our body breaks it down (15). Upregulating these metabolic processes should – in principle – contribute to lowering DHT levels.
The primary pathway through which DHT is metabolized is called glucuronidation (16). This is a fundamental biochemical process in the metabolism not only of DHT and other androgens, but also various toxins and carcinogens. A number of foods have been proposed as inducing the UGT enzymes that underlie glucuronidation. These include primarily cruciferous vegetables, resveratrol and citrus, as well as soy, green tea, dandelion, ellagic acid, ferulic acid and curcumin. The compound in cruciferous vegetables believed to promote glucuronidation is sulforaphane, and the food in which it is found in the highest concentration is broccoli sprouts.
Scalp Hygiene and Exfoliation
The primary concern of many men with hair loss is removing or blocking DHT from the scalp, and this is understandable. But perhaps as important as removing the DHT itself is establishing good scalp hygiene, which is primarily a process of elimination. In other words eliminating the natural and unnatural substances that have built up, which can often contribute to aggravating hair loss problems.
To use a simple analogy, imagine a plant that has to grow through a thick layer of gravel that’s dry and acidic. Even if there is fertile ground beneath, growth is hindered. Our aim is to make it as easy as possible for new hair growth to occur.
The very first step involves exfoliating. Proper scalp exfoliation involves removing dead skin to allow for new healthy cells to grow and works similar to other parts of the body. You also want to be removing any dandruff, as well as all the unnatural chemicals and residues that accumulate in the epidermis from the regular use of cosmetics and hair styling products.
There are endless scalp exfoliating products you can purchase online, but if you want to try a natural method, you can use a homemade exfoliate. To make this yourself you will need:
- Himalyan or Celtic sea salt
- Powdered activated charcoal
- Lemon juice
- A juicing machine (or a blender and muslin cloth)
Take half a tablespoon of salt, 1 teaspoon of powdered activated charcoal and approximately 100ml of mixed ginger and cucumber juice and the juice of 1 whole lemon.
To make the cucumber and ginger juice you will need a juicing machine.
If you don’t yet have a juicer, you can always use an electric blender. Take a large handful of ginger chunks and put them in our high-speed blender along with a whole cucumber. Squeeze in the juice of a whole lemon. Blend up the mixture, without water, or you can add a small amount of water if it’s too dry.
Then, take the mixture and remove the pulp using a muslin cloth or equivalent. This will remove all the pulp and fiber just leaving the cleansing liquid.
Combine all of the ingredients in a small plastic bottle such as a used shampoo bottle and shake thoroughly until well-mixed.
Apply the mixture to the area of scalp that you want to regrow and gently massage into the region. Leave the mixture to sit on the scalp for 5-10 minutes before rinsing out with warm (but not hot) water.
It varies from person to person but there’s a good chance you will need another few peels to fully exfoliate.
Exfoliation is an excellent tool for removing junk that has accumulated on our scalp epidermis, but it is even better to not get it there in the first place. And a few simple lifestyle changes can go a long way in this regard.
Firstly, try to avoid – and preferably eliminate –hairstyling products like gel, mousse, wax. These will typically be laced with harsh chemicals (preservatives, fragrances etc.) and can lead to irritation of the scalp and upsetting of your scalp’s delicate pH balance.
Worse off, as these products dry off they will leave your scalp clogged with debris, leading you to increase your frequency of shampooing. And excessive shampooing is one of the worst things you can do for your scalp, especially if you suffer from hair loss or dandruff. Excessive shampooing strips away of the scalp’s natural oils, forcing it to upregulate its production of sebum, which leads to your head becoming oily very quickly again. A vicious cycle of frequent shampooing then follows.
Removing DHT from your scalp to the point of substantially lowering its levels is certainly feasible, and here we have covered some of the best methods. A multi-pronged approach with simultaneous topical, oral and lifestyle changes is likely to bring about the largest reductions.