Did you know? Niacinamide on its own does not work for thinning hair. Vitamin B3 gives shine and conditions the scalp, and that is all it does. That is why Watermans put seven actives in every wash of Grow Me®: niacinamide for shine, caffeine to energise the scalp, biotin for strength, rosemary to balance the scalp, lupine protein for fuller-looking hair, argan oil for softness and allantoin to calm the scalp. Sulphate-free, vegan, made in the UK, with a 90 Day Money Back Guarantee.
*Independent consumer study of Grow Me® Shampoo, 122 people, three months. Full results on the science page.
The 90 Day Money Back GuaranteeUse it as directed for 90 days and if you are not happy, we refund you.
How it works
Watermans gives backChemotherapy wards have had free Grow Me® from us since 2014, and the nurses there recommend it. Good karma matters to us.
How we give
Real improvements in both my own hair and my clients, from stronger strands to healthier scalp condition with consistent use.
Sarah Sullivan · Certified Trichologist, UK Trichology Clinic, Sheffield
Quality dedicated hair growth treatments such as the Watermans Grow Me range is an excellent starting point to consider. Diligent use for 3 to 4 months can see a reduction in hair thinning and the hope of healthier hair growth.
Dr Anthony Pearce · Specialist Trichologist, Anthony Pearce Trichology, Australia
Watermans products have been a lifesaver for almost every one of our clients. Sulphate free, with no harsh chemicals, and rich in beneficial ingredients such as biotin, caffeine, rosemary, niacinamide and argan oil.
Dr Nick Fisherman · Specialist Trichologist, Hair & Skin Club, Australia
Caffeine
Biotin
Rosemary
Niacinamide
Lupine protein
Argan oil
AllantoinHair does not change in one month. It grows around 1cm a month, and our 122-person study ran for three months. A subscription delivers a fresh set every 30 days at 15% off with free UK shipping, so you never run out mid-routine.
Pause, skip or cancel in two clicks from your account. If it is working, why would you stop?
Caffeine-only shampoos do not work. Grow Me® works as a team, in every wash:
Never with sulphates, parabens or palm oil. The shampoo is vegan. Cruelty-free. Made in the UK. Why sulphate-free matters.
Grow Me® Shampoo: massage into a wet scalp and leave it on for 3 to 4 minutes so the formula can work on the follicles, then rinse. Four washes a week is what the study used.
Condition Me®: on the lengths and ends after every wash, rinse.
Grow More® Elixir: a few drops massaged into the scalp, no rinsing. One bottle of each lasts about 30 days.
Free UK shipping on orders over £45, so the Boost Set always ships free. Dispatched from the UK.
Subscriptions renew every 30 days. Pause, skip, change the date or cancel from your account in two clicks. No phone calls, no emails to chase.
Use as directed and if you are not happy, we will refund you. How it works
Month 1: scalp feels deep-cleaned and refreshed. Hair feels softer and detangles more easily.
Month 2: fewer snapped strands on your brush and pillow. Lengths feel stronger and look shinier.
Month 3: hair looks fuller and feels thicker as less of it breaks. Keep going to keep the result.
Why people trust Watermans
PETABusiness FriendDid you know?
Did you know? Niacinamide on its own does not work for thinning hair. Vitamin B3 gives shine and conditions the scalp, and that is all it does. That is why Watermans put seven actives in every wash of Grow Me®: niacinamide for shine, caffeine to energise the scalp, biotin for strength, rosemary to balance the scalp, lupine protein for fuller-looking hair, argan oil for softness and allantoin to calm the scalp.
Niacinamide is everywhere in skincare and almost nowhere in hair care, which is odd, because the scalp is skin. Here is what vitamin B3 does in a shampoo, what the evidence supports, and why it is the fourth of seven actives in Grow Me® rather than the only one.
Niacinamide, vitamin B3, conditions the scalp and gives hair shine and flexibility, so it looks fuller in the light. The scalp is skin, and niacinamide is one of the best-studied skin conditioning ingredients there is. In Grow Me® it works in the three to four minutes the shampoo sits on the scalp, after caffeine has woken it up.
Flexibility matters more than it sounds. A strand that bends instead of snapping survives brushing, drying and sleeping, and shine is what makes thin hair look thicker, because light bounces off a smooth fibre and shows its full width. In our independent study, 85% of 122 Grow Me® users said their hair looked shiny and 82% said it looked radiant after three months.*
Niacinamide has strong evidence as a skin conditioning ingredient and limited evidence for hair growth, and we do not claim growth for it. What it does in a shampoo is support the condition of the scalp and the look and flexibility of the fibre. The scalp side of growth in Grow Me® comes from caffeine, rosemary, allantoin and the trialled lupine protein.
Niacinamide is also in Grow More® Elixir, Masque Me® and Protect Me®, so the scalp meets it overnight and the lengths meet it in the mask and before heat. It is a quiet ingredient. It is also the one people notice in the mirror first, because shine is immediate.
Because niacinamide does one job well and six others not at all. A shampoo built on vitamin B3 alone would be a conditioning wash with no scalp stimulant and no strength ingredient. Grow Me® pairs it with caffeine to energise the scalp, biotin for strength, rosemary and allantoin for scalp balance, argan oil for softness and a trialled lupine protein for fuller-looking hair.
Yes. Niacinamide is one of the gentlest conditioning ingredients in cosmetics and is used on sensitive facial skin at far higher levels than a shampoo needs. Grow Me® also carries allantoin to calm the scalp, and in our study 84% of users said their scalp felt healthier after three months.*
Watermans products are cosmetics. They care for the scalp and the hair you have, and do not treat hereditary or medical hair loss. If hair is coming out in patches or handfuls, see your GP first.
122 people used unbranded Grow Me® Shampoo four times a week for three months. Here is what they said. See every result.
No single vitamin makes a hair growth shampoo. Grow Me® works as a team: caffeine wakes up the scalp in the first minute, niacinamide conditions it and gives the fibre shine and flexibility, and biotin, rosemary, lupine protein, argan oil and allantoin each do their own job over the next three. Never with sulphates, parabens or palm oil.
For the formula to work, leave it on the scalp for 3 to 4 minutes before washing out.
What the evidence says
Niacinamide is one of the most studied ingredients in skincare. On hair the evidence is about condition and shine, and that is what we claim.
Published research
Niacinamide has decades of published cosmetic research on skin barrier and condition. The scalp is skin, which is why it is in a scalp-first shampoo.
Why it matters: it supports the claim we make, scalp condition and shine, and not the one we do not, growth.
Our own study · 2020
122 people used unbranded Grow Me® four times a week for three months. 85% said their hair looked shiny, 82% radiant, 84% said their scalp felt healthier.*
Why it matters: this tested the whole shampoo, niacinamide and all six teammates.
On the label
Niacinamide is printed on the INCI list of Grow Me® Shampoo, Grow More® Elixir, Masque Me® and Protect Me®.
Why it matters: if it is not on the ingredients list, it is not in the bottle.
Safety
Every Watermans formula has a full independent safety assessment under UK and EU cosmetic law, with a margin of safety calculated for every ingredient, niacinamide included.
Why it matters: it is on your scalp four to five times a week.
What we do not claim
We do not claim niacinamide grows new hair or treats hair loss, and we do not claim Grow Me® does either. We claim Grow Me® is a sulphate-free shampoo with niacinamide and six more actives that most people in an independent study said left their scalp healthier and their hair shinier, thicker and fuller-looking.*
Where it sits in the range
Niacinamide is in the shampoo, the overnight elixir, the mask and the heat protection, so the scalp and the lengths both meet it.
Prices and ingredient lists checked on 12 November 2026 against the INCI list printed on each product. Sets that include these products are listed in the grid below.
Shop the ingredient
Every product below contains niacinamide. Start with Grow Me®, or take the set and give the full routine its 90 days.
Every photo below was uploaded by the customer with their verified review. We have trimmed some quotes for length. Results vary from person to person.
50 days inCustomer's own photo“After 50 days I am very pleased. My hair might not feel thicker in a ponytail but it looks thicker and you can't see my scalp through my hair any more. I have ordered my second bottle to carry on for the recommended 3 months.”
7 weeks inCustomer's own photo“I've been using this shampoo and conditioner for about 6 to 7 weeks due to my hair randomly thinning. The improvement I've seen already is amazing. My confidence with my hair is much better and I've since purchased the set again and the hair mask.”
7 months inCustomer's own photo“I've been using this shampoo and conditioner for 6 to 7 months now and the difference in my hair is amazing. The condition of my coloured blonde hair is amazing, no breakage, super soft. I love it that much I bought the salon size in both.”
Long-term userCustomer's own photo“Rapid weight loss after surgery caused dramatic hair loss. I truly thought I was going to go bald. Then I discovered Watermans and won't use any other shampoo and conditioner. My hair is in beautiful condition, it's thicker than ever and I couldn't be happier.”
First weekCustomer's own photo“I haven't been using this product for a week yet and I'm already seeing improvement. My hair is fuller, it's glossy. I also have scalp psoriasis and it hasn't bothered me at all since I've been using this product.”
2 years inCustomer's own photo“I have been using Watermans for over 2 years and the proof is in my photos. I was a tape hair extension person for years so my hair was damaged and short with ratty ends. Now everyone asks me what I use.”
Repeat buyerCustomer's own photo“I had very thin hair before this shampoo. My hair is so healthy and thick now. I don't want to use any other shampoo but Grow Me.”
The real cost of the routine
Grow Me® works on its own. People who get the best results use all three, every wash, every night. Here is what the full routine costs either way.
Prices checked November 2026. Free gifts are added automatically at checkout while stocks last.
£53.40£45.39 a delivery · £1.51 a day
The complete hair loss routine, delivered before you run out. Use all three together for optimal results and give it the full 90 days.
Every Watermans formula is built on ingredients with their own test data, combined so they work on the scalp and the strand together.
Our actives are tested by the labs that make them. Our lupine protein was tested in the lab and on volunteers by our ingredient manufacturer. Caffeine, biotin, rosemary and niacinamide are among the most studied hair ingredients there are.
Our lupine protein is a trademarked active from our ingredient manufacturer: a hydrolysed lupine protein rich in peptides, trace elements and vitamins. It is in Grow Me® Shampoo and Grow More® Elixir.
Most shampoos lean on one hero ingredient. Grow Me® combines caffeine, biotin, rosemary, niacinamide, lupine protein, argan oil and allantoin, so the scalp and the strand are looked after in the same wash.
We have watched thousands of hair loss brands and products come and go, every one claiming to combat hair loss. Since 2012 Watermans has sold 6.5 million bottles, won a Queen's Award for Enterprise and run a three-month consumer study on 122 people. We are still standing. We must be doing something right.
Ingredient tests are carried out by the ingredient manufacturer. Our own three-month consumer study of Grow Me® covered 122 people.
FAQs
Watermans products are cosmetics. They are not medicines and do not treat medical hair loss. If your hair is falling out suddenly, in patches, or you are worried, please see your GP or a trichologist first. Prices, stock and ingredient lists on this page were checked on 12 November 2026.
Yes. Niacinamide, vitamin B3, conditions the scalp and gives the hair fibre shine and flexibility, so it bends instead of snapping and looks fuller in the light. In our study 85% of 122 Grow Me® users said their hair looked shiny after three months.* It is one of seven actives in the shampoo.
Niacinamide has strong evidence for skin and scalp condition and limited evidence for growth, so we do not claim growth for it. In Grow Me® the scalp stimulant is caffeine, and rosemary, allantoin and a trialled lupine protein work alongside it. Niacinamide looks after condition and shine.
Yes. Niacinamide is among the gentlest conditioning ingredients in cosmetics and is used on sensitive facial skin at higher levels than a shampoo carries. Grow Me® is used four to five times a week, and every Watermans formula is independently safety assessed.
Grow Me® Shampoo, Grow More® Overnight Scalp Elixir, Masque Me® hair mask and Protect Me® heat protection all list niacinamide on the label. The shampoo is the daily step; the others add it overnight, weekly and before heat styling.
Three to four minutes on a wet scalp, four to five washes a week. The contact time is the point: a shampoo that is rinsed straight off is a detergent and a perfume. Massage it in with your fingertips, leave it, then rinse and condition the lengths.
In an independent three-month home-use study of unbranded Grow Me® Shampoo, 72% of users said their hair loss had noticeably slowed, 83% said their hair looked fuller, 82% said it felt thicker and 83% said it felt stronger. These are consumer perception results, not a clinical trial, and we say so on every page.
Grow Me® Shampoo is vegan and cruelty-free, made in the UK, and formulated without sulphates, parabens or palm oil. Every Watermans product except Condition Me® conditioner is vegan. No Watermans product is tested on animals.
Yes. The 90 Day Money Back Guarantee covers your first order of Grow Me®, Condition Me®, Grow More®, Masque Me® and Protect Me®. Use the product as directed for 90 days and, if you are not happy, we refund it. Hair grows around a centimetre a month, so 90 days is the honest minimum to judge any routine.
A kiss of life for hair
*Based on an independent consumer study of 122 people (104 women, 18 men) who used unbranded Grow Me® Shampoo four times a week for three months. Consumer perception results: the percentages are the share of users who agreed with each statement. Individual results vary. Ingredient research described on this page is published research into the ingredient, or the ingredient manufacturer's own tests of the active on its own, not tests of the finished Watermans products. Watermans products are cosmetics, not medicines, and do not treat medical hair loss. Prices, ingredient lists and review counts checked on 12 November 2026.
