Hormones and Endocrine Health
Finding more hair on the pillow or in the shower drain is enough to send most men searching at midnight. The answer is usually genetics, but not always, and the cases that are not genetic are often the ones you can fix completely.
The first job is working out which one you have.
Androgenetic alopecia is the most common cause by a wide margin, affecting around half of men by the age of 50. It is driven by dihydrotestosterone, DHT, which is made from testosterone by the enzyme 5-alpha reductase.
In genetically susceptible follicles, DHT progressively shrinks each hair. Every growth cycle produces a thinner, shorter, lighter hair until the follicle stops producing visible hair at all.
The pattern gives it away: recession at the temples and thinning at the crown, while the back and sides stay thick. Those back-and-side follicles are genetically resistant to DHT, which is exactly why hair transplants take hair from there.
Timeline: gradual, over years. Not sudden.
A sudden, diffuse shed across the whole scalp, typically starting two to three months after a significant stressor. Triggers include a high fever or serious illness, surgery, a crash diet, severe emotional stress, rapid weight loss, and starting or stopping certain medications.
The stressor pushes a large number of follicles into the resting phase at once, and they shed together weeks later.
The key detail is the delay. People look for a cause in the last fortnight when the trigger was three months ago.
Outlook: it usually recovers on its own within six to nine months once the trigger is gone. This is the one worth ruling out before assuming the worst.
Low iron stores are the most studied. Ferritin, the marker of iron stores, is frequently low in people with diffuse shedding, and correcting a genuine deficiency is reasonable. Severe protein deficiency, which can happen during aggressive dieting, also causes shedding. Zinc and vitamin D have associations, though the evidence for supplementing people who are not deficient is weak.
Test before you supplement. Ferritin, vitamin D and a basic panel are cheap. The blood test selector builds a hair-focused panel from what you are trying to rule out.
Both underactive and overactive thyroid can cause diffuse thinning. It often comes with other clues: fatigue, weight change, feeling unusually cold or hot, changes in skin.
A thyroid test is simple and worth doing, particularly since thyroid problems are common in India. The thyroid assessment reads the full pattern rather than TSH alone.
An autoimmune condition producing round, smooth, well-defined bald patches, often coin-sized, sometimes in the beard. Once you know what to look for, it looks nothing like pattern hair loss.
It needs a dermatologist. Regrowth is common, and effective treatments exist.
This is the one most relevant to anyone using or considering anabolic steroids, and it catches people by surprise.
Compounds that are DHT derivatives, or that raise DHT, accelerate pattern hair loss in genetically susceptible men. They do not create the susceptibility. They speed up a process that would have happened more slowly anyway, sometimes compressing years of hair loss into months.
There is also a widely misunderstood interaction. Testosterone converts to DHT through 5-alpha reductase, so blocking that enzyme with finasteride protects the scalp. Nandrolone does the opposite. The same enzyme converts it into a much weaker compound, so the enzyme is actually protecting you. Block it with finasteride and more of the stronger parent compound reaches the follicle. Finasteride alongside nandrolone can make hair loss worse, not better.
The hairloss-proof cycle assessment works through nineteen compounds and shows which ones finasteride helps with and which it does not.
The hair loss protocol engine works through six causes from your pattern, timeline and history, and points to the one worth addressing first.
Pattern hair loss has two mainstays with solid evidence. Minoxidil, applied topically or taken orally under medical supervision, prolongs the growth phase. Finasteride reduces DHT production and slows or halts progression in most men who take it consistently. Both work best started early, because they are far better at keeping hair than regrowing hair that is long gone. Finasteride and dutasteride are prescription medicines and carry a small risk of sexual side effects that should be discussed with a doctor before starting. Ketoconazole shampoo and microneedling are sometimes used alongside them.
Telogen effluvium needs the trigger removed and time. Deficiencies need correcting. Thyroid problems need treating. Alopecia areata needs a dermatologist.
The hair loss market is full of products with more marketing than evidence behind them.
Biotin. It genuinely helps only in the rare case of true biotin deficiency. In everyone else it does little for hair, and at high doses it interferes with blood tests, including thyroid tests, which can send you down the wrong path entirely.
Hair gummies and multivitamins. Unless you are deficient in something, they do not stop pattern hair loss.
Onion juice, herbal oils and DHT-blocking shampoos. The evidence ranges from very weak to absent. Some may do no harm. None is a substitute for treatments with trial evidence behind them.
The most expensive mistake is spending a year on these while pattern loss progresses, because hair that is lost is far harder to regain than hair that is held.
Gradual loss at the temples and crown is almost always pattern hair loss, driven by DHT. Sudden diffuse shedding often traces back to a stressor two or three months earlier and usually recovers. Rule out thyroid and iron with a cheap blood test before assuming the worst, and if you use androgens, know that finasteride does not protect against every compound.
Most commonly male pattern hair loss, driven by DHT acting on genetically susceptible follicles. Other causes include telogen effluvium after a stressor, iron or protein deficiency, thyroid problems, alopecia areata and androgenic drugs.
Genetic loss is gradual and follows the temple and crown pattern. Stress-related shedding is sudden, diffuse across the whole scalp, and usually begins two to three months after the stressful event.
Telogen effluvium usually recovers within six to nine months once the trigger has been removed.
Ferritin for iron stores, TSH for thyroid, vitamin D, and a complete blood count are the common starting points. A dermatologist may add others depending on the pattern.
No. It reduces the conversion of testosterone into the more potent DHT, which helps. But nandrolone is converted by the same enzyme into a weaker compound, so blocking it with finasteride can increase hair loss from nandrolone.
They are much better at stopping further loss than regrowing hair that has been gone for years. Some regrowth of recently miniaturised hair is common, which is why starting early matters.
This article is educational and is not medical advice. See the medical disclaimer.
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