Hair loss supplements for men: do they actually work?
Quick answer
Yes, some hair loss supplements do work, but only if they contain the right ingredients at the doses that have actually been studied. The botanical extract with the most evidence in male androgenetic alopecia is Saw Palmetto: a systematic review of 5 clinical trials and 2 cohort studies found improvements in hair quality, density and count with oral doses of 100-320 mg/day and no relevant side effects. The problem is that most capsules on the market carry a fraction of that dose. A supplement won't replace medical treatment or a topical, but a well-formulated one is the third layer of a serious anti-hair-loss routine.
- Finasteride vs natural extracts
- DHT is part of the story, not all of it
- The problem with most supplements: they're underdosed
- Saw Palmetto: what the clinical studies say
- What's in Growzilla (and why)
- Comparison table: studied doses vs what's typical
- Who is it for?
- The Siwon approach: inside + outside
- FAQ
- Sources and evidence
If you want to understand why hair falls out, what DHT is and what happens in your follicle when your hairline starts retreating faster than your fringe can cover, go back and read our complete guide to hair loss in men (reviewed by a doctor).
Today we go one step further: do hair loss supplements actually work? Are they pure marketing? Are they a real alternative to finasteride?
Spoiler: it depends on how they're formulated, on the dose, and on how you use them.
Finasteride vs natural extracts: neither side wins outright
Finasteride (which is a medicine and must ALWAYS be prescribed by a doctor) works. It inhibits the type II 5-alpha-reductase enzyme and reduces the conversion of testosterone into DHT, the main culprit behind follicle miniaturisation.
In other words: it slows down going bald.
The catch?
It's a medicine. And like any medicine, some people report side effects (libido, mood, etc.). That fear sends a lot of people looking for alternatives or "natural DHT blockers".
And yes, there are plant extracts with interesting evidence on DHT modulation. But the dose matters more than the marketing.
DHT is part of the story. Not all of it.
When we talk about male androgenetic alopecia we tend to boil everything down to DHT. And yes, it's the key factor. But not the only one. Androgenetic alopecia involves:
- Genetics + DHT.
- Inflammation around the follicle.
- Oxidative stress.
- Micronutrient deficiencies or hormonal imbalance.
If you only attack one, you leave three playing against you. And that's exactly where a well-formulated nutricosmetic makes sense.
The problem with most supplements: they're "underdosed"
On the market you'll typically see:
- 80–160 mg of saw palmetto (it sounds exotic, and anyone who's done their reading knows it matters) + 1 mg of biotin "because it looks nice on the label" + zinc in poorly absorbed forms.
We don't like throwing shade. We'll say no more, but we think you get the idea...
Saw Palmetto: what the clinical studies say
Saw Palmetto (Serenoa repens) is probably the most studied botanical extract in male hair health. Its mechanism goes straight to the root of the problem: it inhibits both isoenzymes of 5-alpha-reductase, reducing the conversion of testosterone into DHT within the follicle itself, without altering blood hormone levels. That's what sets it apart from the drugs and what explains its good tolerance profile.
Don't take our word for it; the literature says so:
Systematic review — Evron et al., 2020
Analysed 5 randomised clinical trials and 2 cohort studies of oral and topical Saw Palmetto (100–320 mg) in androgenetic alopecia and telogen effluvium. Results: 60% improvement in overall quality +27% total hair count more density in 83% shedding stabilised in 52%, with no serious adverse events.
Double-blind, randomised, placebo-controlled — Prager et al., 2002
Men aged 23 to 64 with mild-to-moderate androgenetic alopecia took liposterolic Saw Palmetto extract + beta-sitosterol. 60% improved versus 11% on placebo.
Saw Palmetto 320 mg/day vs finasteride 1 mg, 2 years — Rossi et al., 2012
38% of patients on Saw Palmetto increased hair growth, versus 68% on finasteride. Less powerful than the drug, yes; but a real effect, without the side effects that make so many people quit treatment.
16-week placebo-controlled trial — Sudeep et al., 2023
With an extract standardised in fatty acids and phytosterols, the oral form reduced shedding by up to 29%, increased density by 5% and significantly lowered blood DHT compared with placebo.
The small print that matters: all of these studies used standardised extract (liposterolic, rich in fatty acids and phytosterols) at 200-320 mg/day and over months, not weeks. Unstandardised berry powder at 80 mg "for show" is not the same thing. The sensible minimum course is 4-6 months. If you take anticoagulants, check with your doctor first.
If you're going to play on the evidence pitch, play like a pro
That's why we launched Growzilla. Growzilla = grow + Godzilla: if you're going to grow your mane, do it kaiju-style and unleashed. Working with doses aligned with the ranges used in clinical studies on hair health. Hold my drink:
Want to attack DHT from the inside? Here you go:
- Saw Palmetto standardised to 85%: 320 mg
- Pumpkin seed extract: 400 mg
- Nettle: 200 mg
- Pygeum africanum: 20 mg
Want structural nutrients, protection against oxidative damage and good microcirculation on top? Enter:
- Biotin 2.5 mg – 5000% NRV
- Zinc bisglycinate 10 mg – 100% NRV
- Vitamin D3 25 µg – 500% NRV
- Vitamin B6, selenium, astaxanthin, MSM and silicon, ginkgo, ginseng... and so on up to 20 micronutrients and extracts at the dose that makes the difference.
Honestly, nothing more would fit in the capsule. Some ingredients come from far away… because they aren't made in Spain. The capsules are 100% vegan, in colours that nod to Dr. Mario. The manufacturing setup we've built… let's just say it was a marathon. The point is: this is not a capsule with three trendy ingredients. It's a beast. A proper monster.
Comparison table: studied doses vs what's typical on the market
So you don't have to trust us: grab the label of any hair supplement you have at home and compare it with this table.
| Ingredient | Daily dose in studies | What's typical in "others" | Growzilla (2 caps) |
|---|---|---|---|
| Saw Palmetto (standardised extract) | 200–320 mg (Prager 2002, Rossi 2012, Evron 2020) | 80–160 mg, often unstandardised berry powder | 320 mg at 85% |
| Pumpkin seed | 400 mg (Cho 2014, 24 weeks, double-blind) | Absent or 100–200 mg | 400 mg |
| Nettle (Urtica dioica) | In vitro evidence on 5-alpha-reductase; combined with Saw Palmetto in prostate trials | Absent | 200 mg |
| Pygeum africanum | In vitro and indirect evidence (5-alpha-reductase inhibition) | Absent | 20 mg |
| Biotin | Contributes to the maintenance of normal hair (authorised EU claim); most useful when deficient | 0.05–1 mg | 2.5 mg (5000% NRV) |
| Zinc | Contributes to the maintenance of normal hair (authorised EU claim) | Zinc oxide (low absorption) | 10 mg bisglycinate |
| Vitamin D3 | Deficiency is common; involved in the follicle cycle | 5 µg or absent | 25 µg (500% NRV) |
| Antioxidants and microcirculation (astaxanthin, selenium, ginkgo, ginseng, MSM, silicon) | Act on oxidative stress and follicle blood supply | Usually 1–2 of them | All of them, up to 20 actives |
"Others" reflects the most common formulations in mass-market hair supplements reviewed by our team; each brand is responsible for its own label. Study doses refer to the conditions of each trial; different formulations and people may give different results.
Who is Growzilla for?
- Men in early or intermediate stages of hair loss.
- If you're starting to notice diffuse shedding.
- If you take finasteride and want to maximise results.
- If you don't want to start drug treatment and are looking for comprehensive support.
It's not for:
- Areas where the follicle has been inactive for years (miracles are a different department).
- Scarring alopecia or other follicle disorders.
- Impatient people expecting a thick mane in a month.
The Siwon approach: inside + outside, from every angle
Above, below, behind and from every angle. If you want to go hard and slow down hair loss:
- From the inside – Nutritional and anti-DHT support with Growzilla.
- From the outside – Stimulate the follicle directly with the biomimetic peptides (Capixyl™ at 5%), caffeine and microcirculation-boosting actives in Follicool, our anti-hair-loss spray serum.
- And the base – A clean, nourished scalp every shower with Hairicane, the strengthening shampoo with the botanical complex at 3%.
It's the three-layer routine we explain in our hair loss guide: wash, treat, reinforce. And if you move on to medical treatment, all three layers keep adding up.
The star, from within
34,99 €
Growzilla
Holistic support for healthy, strong, faster-growing hair. Nutritional supplement for men 18+ worried about hair loss. Multi-factor formula with over 20 science-backed botanical extracts and micronutrients.
- Saw Palmetto 320 mg at 85%: the dose used in clinical trials
- Biotin, zinc bisglycinate and D3 at real doses, not label doses
- 60 vegan capsules = 1 month (2 a day)
P.S.: This post is sponsored by Growzilla – your daily ration of vitamins, minerals, micronutrients and 20+ botanical extracts for a mane worth grabbing.
FAQ about hair loss supplements
Do hair loss supplements work?
They can work when they contain clinically studied actives at the doses that were studied. Saw Palmetto is the extract with the most support in male androgenetic alopecia (systematic review of 5 clinical trials). A supplement with 80 mg of saw palmetto and decorative biotin is far less likely to do anything than one formulated at 320 mg with the rest of the cofactors.
Is Saw Palmetto an alternative to finasteride?
Not an equivalent one. In the only 2-year comparative study, finasteride improved growth in 68% of patients and Saw Palmetto 320 mg in 38%. It's less potent, but it acts on the same enzyme, has a very good tolerance profile and can be combined with the drug to maximise results. The decision to start finasteride is always your doctor's.
What dose of Saw Palmetto has been studied for hair?
Between 200 and 320 mg a day of standardised extract (liposterolic, rich in fatty acids and phytosterols), for a minimum of 4-6 months. Growzilla contains 320 mg standardised to 85%.
How long does a hair loss supplement take to work?
The follicle works in cycles of months. The sensible approach is to assess at 3 months and make decisions at 6. Take a photo with the same light and angle every 3 months: it's the only objective way to know whether you're winning.
Does biotin make hair grow?
Biotin contributes to the maintenance of normal hair, but deficiency is rare and taking extra doesn't turn a miniaturised follicle into a new one. That's why serious supplements combine it with actives that work on the hormonal cause, such as Saw Palmetto.
Can I take Growzilla with Follicool or with medical treatment?
Yes. Growzilla works from the inside and Follicool from the outside, on the same follicle; they're complementary. It's also compatible with medical treatments, although if you take medication (especially anticoagulants) or have a medical condition, check with your doctor first.
Does Saw Palmetto have side effects?
No serious adverse events have been reported in clinical trials in alopecia; the most common are mild digestive discomfort. It doesn't alter blood hormone levels, unlike the drugs. Use caution if you take anticoagulants.
When should I see a dermatologist?
If the shedding is sudden, patchy, accompanied by pain, crusting or inflammation, or if you're losing hair on other parts of the body. And if the pattern is clearly androgenetic and progressive, you can also consult from the start to weigh up all the options.
Sources and evidence
The studies cited in this article, so you can read them yourself:
- Evron E. et al. Natural Hair Supplement: Friend or Foe? Saw Palmetto, a Systematic Review in Alopecia. Skin Appendage Disord (2020).
- Prager N. et al. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med (2002).
- Rossi A. et al. Comparative effectiveness of finasteride vs Serenoa repens in male androgenetic alopecia: a two-year study. Int J Immunopathol Pharmacol (2012).
- Sudeep H.V. et al. Oral and Topical Administration of a Standardized Saw Palmetto Oil Reduces Hair Fall and Improves Hair Growth in Androgenetic Alopecia: a 16-week RCT. Clin Cosmet Investig Dermatol (2023).
- Cho Y.H. et al. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial. Evid Based Complement Alternat Med (2014).
- Igielska-Kalwat J. The Use of Serenoa Repens (Saw Palmetto) in Hair Care Products. Biomed J Sci & Tech Res (2019) [PDF].
- Regulation (EU) 432/2012 — authorised health claims (biotin, zinc, selenium).
So, what now?
Look at the label of the supplement you have at home. If the saw palmetto doesn't reach 300 mg, now you know why you haven't noticed anything. Start from the inside and take your control photo.
Start with GrowzillaNote: this content is for informational purposes only and does not replace the diagnosis or advice of a healthcare professional. Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose. If your hair loss is sudden, patchy, progressive or accompanied by other symptoms, see a dermatologist.