Working paper

How HR01.1 was formulated

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  • Revised Apr 2026
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HR01.1 is a daily oral protocol formulated around ten actives selected from the published nutritional literature on hair. This document explains how we arrived at each active, why each is dosed at the level it is, and the framework that holds the formulation together.

Framework

The four contributors framework

Hair growth, shedding, and renewal are governed by biological processes that nutritional formulations can address in part. HR01.1 is structured around four contributors to follicle and hair-fibre health that the published literature has investigated most extensively.

The framework is descriptive, not prescriptive. Hair biology is interconnected, these contributors do not operate in isolation, and no single contributor governs the hair you have. The framework exists because it makes the formulation legible: each active in HR01.1 can be located within one or more of the four contributors.

Contributors

Four contributors, drawn

Hormonal

Androgen-related follicle behaviour

The endocrine system shapes follicle behaviour over time. Androgens, particularly dihydrotestosterone (DHT), are the most extensively studied hormonal influence on the hair growth cycle, and follicle sensitivity to them varies by genetics, age, and life stage.

The published nutritional literature has investigated several botanicals in the context of androgen-related hair concerns. HR01.1 includes two of these.

  • Saw Palmetto Extract320 mg
  • Pumpkin Seed Oil400 mg

Oxidative

Cellular antioxidant defences

Hair follicles are metabolically active and produce reactive oxygen species as a by-product of normal cellular function. Cellular antioxidant defences counter this, and their efficiency depends on nutritional status.

The published research has investigated antioxidant compounds, particularly members of the vitamin E family and trace minerals with antioxidant cofactor function in this context.

  • Tocotrienol Complex100 mg
  • Selenium55 µg

Structural

Keratin synthesis and disulphide bond formation

Hair fibre is composed primarily of keratin, a sulphur-rich fibrous protein assembled from specific amino acids. The synthesis of keratin requires both the amino acid building blocks and mineral cofactors involved in disulphide bond formation.

This is the contributor with the clearest authorised regulatory framework: zinc and selenium both have GB-authorised health claims for the maintenance of normal hair.

  • L-Cystine450 mg
  • L-Lysine450 mg
  • MSM500 mg
  • Zinc15 mg

Stress-related

Stress-response and hair growth cycle

Physiological and psychological stress alter the hair growth cycle. Cortisol patterns, sleep quality, and overall physiological load influence the proportion of follicles in active growth (anagen) versus shedding (telogen) phase.

The published research has investigated nutritional support for stress-response systems, including adaptogenic botanicals long used in traditional medicine and now examined in modern clinical trials.

  • Ashwagandha Extract300 mg
  • Vitamin D350 µg

Doses

Per-active dose rationale

Each active in HR01.1 is dosed at a level reflecting the published nutritional literature, balanced against safe upper intake limits where these are set by UK guidance, and balanced against the formulation's combined load within a four-capsule daily dose. Where the dose in HR01.1 sits below the levels investigated in monotherapy clinical trials, this is stated and explained.

Each active's dose in HR01.1 against the range investigated in the published literature, with the reference it comes from.
ActiveHR01.1 doseLiterature rangeReference
Pumpkin Seed Oil400 mg400 mgCho et al. 2014
Saw Palmetto Extract320 mg100–320 mgEvron et al. 2020
Tocotrienol Complex100 mg100 mgBeoy et al. 2010
L-Cystine450 mg250–500 mgVKM 2016
L-Lysine450 mg1,000–1,500 mgAlmohanna et al. 2019
MSM500 mg1,000–3,000 mgSee rationale below
Ashwagandha Extract300 mg300–600 mgChandrasekhar et al. 2012
Vitamin D350 µg≤100 µgUK SACN guidance
Zinc15 mg≤25 mgUK SACN guidance
Selenium55 µg≤300 µgUK SACN guidance

* Standard standalone supplement range for L-Cystine; safe upper intake assessment 750 mg/day for adults (VKM 2016).

† HR01.1 dose is below the standalone trial range. See the per-active rationale for the formulation prioritisation.

The actives

Ten entries, one per active

Pumpkin Seed Oil

400 mg

Cold-pressed oil from Cucurbita pepo seeds, naturally rich in phytosterols (including delta-7 phytosterols), unsaturated fatty acids, and tocopherols.

The 400 mg daily dose reflects the protocol used in Cho et al. (2014), a 24-week randomised, double-blind, placebo-controlled trial published in Evidence-Based Complementary and Alternative Medicine. The trial investigated cold-pressed pumpkin seed oil at 400 mg daily in 76 men with mild-to-moderate androgenetic alopecia.

Form
Cold-pressed oil
Source
Cucurbita pepo seed
Contributor
I · Hormonal
Characterised by
Delta-7 phytosterols
Evidence
24-week RCT, n=76

Saw Palmetto Extract

320 mg

Lipophilic fruit extract from Serenoa repens, naturally containing fatty acids, phytosterols, and small concentrations of polyphenolic compounds. The fatty acid fraction is the most studied compositional feature.

The 320 mg daily dose sits at the upper end of the dose range investigated in published trials of saw palmetto in androgen-related contexts. Evron et al. (2020), a systematic review published in Skin Appendage Disorders, identified an investigated dose range of 100–320 mg across the published literature on oral and topical saw palmetto supplements in alopecia.

Form
Lipophilic extract
Source
Serenoa repens fruit
Contributor
I · Hormonal
Characterised by
Fatty acid fraction
Evidence
Systematic review, 2020

Tocotrienol Complex

100 mg

A mixed-isoform extract of tocotrienols, the less-common members of the vitamin E family, distinct from the alpha-tocopherol found in most vitamin E supplements. Sourced from palm fruit.

The 100 mg daily dose reflects the protocol used in Beoy et al. (2010), an 8-month trial published in Tropical Life Sciences Research. The trial investigated mixed tocotrienol supplementation at 100 mg daily in 38 adult volunteers with hair loss.

Form
Mixed-isoform extract
Source
Palm fruit
Contributor
II · Oxidative
Family
Vitamin E
Evidence
8-month trial, n=38

L-Cystine

450 mg

A sulphur-bearing amino acid composed of two cysteine residues linked by a disulphide bond. L-Cystine is one of the principal amino acids in keratin (which contains approximately 16% L-cystine by composition) and is structurally significant in hair fibre formation.

The 450 mg daily dose sits within the standard standalone supplemental range for L-Cystine (typically 250–500 mg per capsule across European nutritional supplements) and well within the upper safe intake assessment of 750 mg/day for adults established by the Norwegian Scientific Committee for Food Safety. This is meaningfully higher than the L-Cystine content investigated in published multi-ingredient hair supplement trials, including Lengg et al. (2007), where L-Cystine was one component within a B-vitamin and medicinal yeast complex at lower per-dose levels.

Form
Amino acid
Structure
Two cysteine residues
Contributor
III · Structural
In keratin
About 16% by composition
Evidence
VKM safety assessment

L-Lysine

450 mg

An essential amino acid (one the human body cannot synthesise from other compounds) involved in collagen synthesis and iron absorption. While L-Lysine is not itself a primary structural component of hair, dietary lysine status interacts with iron metabolism, which is required for hair follicle cycling.

The role of L-Lysine in hair-related nutrition has been reviewed in Almohanna et al. (2019) in Dermatology and Therapy and Guo and Katta (2017) in Dermatology Practical & Conceptual. Published clinical investigations of L-Lysine specifically for hair have used 1,000–1,500 mg daily, paired with iron supplementation in women with chronic telogen effluvium and low ferritin status.

The 450 mg daily dose in HR01.1 is below those trial levels. This is a deliberate formulation decision. A four-capsule daily dose carries a finite mass of actives; we have prioritised that capsule load toward the actives with the most direct evidence in hair-specific clinical research, Pumpkin Seed Oil, Saw Palmetto, Tocotrienol, Ashwagandha, and the regulated minerals, and dosed those at the levels investigated in the literature. L-Lysine is included to support the formulation's amino acid profile alongside L-Cystine, not as a standalone replacement for the iron-paired protocols described in the literature. Customers with diagnosed iron-related telogen effluvium should consult a healthcare professional, who can advise on iron supplementation and L-Lysine dosing appropriate to their ferritin status.

Form
Essential amino acid
Contributor
III · Structural
Interacts with
Iron metabolism
Evidence
Reviews, 2017 and 2019

MSM

500 mg

Methylsulfonylmethane, an organic sulphur compound. MSM functions as a bioavailable sulphur donor, and sulphur is required for keratin synthesis (the disulphide bonds that give hair its structural integrity are sulphur-based).

Published clinical research on MSM specifically for hair has typically investigated doses of 1,000–3,000 mg daily as a standalone intervention. The 500 mg daily dose in HR01.1 is below those levels, by deliberate formulation decision. Capsule load is finite; sulphur is already supplied through L-Cystine, which sits at meaningful nutritional levels in the formulation. MSM at 500 mg is included as a complementary sulphur source rather than as a primary intervention, with the priority of the protocol allocated to actives with stronger and more direct hair-specific clinical evidence.

Form
Organic sulphur compound
Role
Bioavailable sulphur donor
Contributor
III · Structural
Supports
Disulphide bond formation

Ashwagandha Extract

300 mg

Root extract of Withania somnifera, traditionally used in Ayurvedic practice and now widely studied in modern nutritional research. Contains naturally occurring withanolides as the characterising compounds.

The 300 mg daily dose sits at the lower end of doses investigated in clinical research on standardised ashwagandha root extract. Chandrasekhar et al. (2012), a 60-day randomised, double-blind, placebo-controlled trial published in the Indian Journal of Psychological Medicine, investigated 300 mg of high-concentration full-spectrum ashwagandha root extract twice daily in 64 adults under stress. We have selected the once-daily 300 mg dose to deliver ashwagandha at the lower end of the investigated range.

Note: ashwagandha is currently under active review by the UK Food Standards Agency Committee on Toxicity. We monitor this review closely and will reformulate if regulatory guidance changes.

Form
Root extract
Source
Withania somnifera
Contributor
IV · Stress-related
Characterised by
Withanolides
Evidence
60-day RCT, n=64

Vitamin D3

50 µg · 1,000% NRV

Cholecalciferol, the form of vitamin D synthesised by the human skin in response to UVB exposure. The active form involved in cellular signalling. Sourced from lichen (vegan-suitable).

The 50 µg (2,000 IU) daily dose reflects the upper end of doses investigated in the published research on vitamin D status, balanced against UK Tolerable Upper Intake Level guidance (100 µg/day from all sources). This dose is appropriate for individuals not taking other vitamin D supplements; cumulative intake guidance applies.

Form
Cholecalciferol
Source
Lichen, vegan-suitable
Contributor
IV · Stress-related
NRV
1,000%
Note
Cumulative intake applies

Zinc

15 mg · 150% NRV

Provided as zinc citrate, a chelated form selected for bioavailability. Zinc is required as a cofactor for over 300 enzymatic processes, including those involved in keratin synthesis. Zinc is the subject of an authorised GB health claim for the maintenance of normal hair, skin, and nails.

The 15 mg daily dose is supplied at 150% of the Nutrient Reference Value, well within the UK Tolerable Upper Intake Level of 25 mg/day. This dose is appropriate for individuals not taking other zinc supplements; cumulative intake guidance applies.

Form
Zinc citrate
Contributor
III · Structural
GB claim
Normal hair, skin, nails
NRV
150%
Note
Cumulative intake applies

Selenium

55 µg · 100% NRV

Provided as selenomethionine, the form found in dietary protein sources. Selenium is required as a cofactor for selenoenzymes including glutathione peroxidase, which contributes to cellular antioxidant defences. Selenium is the subject of an authorised GB health claim for the maintenance of normal hair and nails.

The 55 µg daily dose is supplied at 100% of the Nutrient Reference Value, well within the UK Tolerable Upper Intake Level of 300 µg/day.

Form
Selenomethionine
Contributor
II · Oxidative
GB claim
Normal hair and nails
NRV
100%

Claims

What we don't claim

The published research on the actives in HR01.1 has investigated many endpoints; hair count, hair density, shedding, tensile strength, scalp condition. Some of these studies have reported notable findings.

Under UK food law, only three claims about the actives in HR01.1 are formally authorised on the GB Nutrition and Health Claims Register: that Vitamin D3 contributes to the normal function of the immune system, that Zinc contributes to the maintenance of normal hair, skin and nails, and that Selenium contributes to the maintenance of normal hair and nails.

We make those three claims because they are authorised. We do not make claims about the other actives including Pumpkin Seed Oil, Saw Palmetto, Tocotrienol, and Ashwagandha, even though we have selected and dosed them based on the published research.

The formulation reflects the literature. The label reflects the regulatory framework. We are comfortable with the gap between the two, and we think you should understand it before you buy.

Reformulation

Reformulation philosophy

A formulation is a statement about what the published evidence currently supports. The evidence develops. So does the formulation.

When new published research changes our understanding of a dose, an active, or a contributor, HR01.1 is updated. Each revision is logged, dated, and explained on the Reformulation Log (coming soon). Subscription customers receive each new revision automatically when it is released.

This is the discipline that distinguishes a protocol from a product. A product is sold and forgotten. A protocol is maintained.

References

Cited in this document

  1. Cho YH, Lee SY, Jeong DW, et al. Effect of pumpkin seed oil on hair growth in men with androgenetic alopecia: a randomized, double-blind, placebo-controlled trial. Evidence-Based Complementary and Alternative Medicine. 2014;2014:549721.

    View paper (opens in a new tab)
  2. Evron E, Juhasz M, Babadjouni A, Mesinkovska NA. Natural hair supplement: friend or foe? Saw palmetto, a systematic review in alopecia. Skin Appendage Disorders. 2020;6(6):329-337.

    View paper (opens in a new tab)
  3. Beoy LA, Woei WJ, Hay YK. Effects of tocotrienol supplementation on hair growth in human volunteers. Tropical Life Sciences Research. 2010;21(2):91-99.

    View paper (opens in a new tab)
  4. Lengg N, Heidecker B, Seifert B, Trüeb RM. Dietary supplement increases anagen hair rate in women with telogen effluvium: results of a double-blind, placebo-controlled trial. Therapy. 2007;4(1):59-65.

    View related review (opens in a new tab)
  5. Almohanna HM, Ahmed AA, Tsatalis JP, Tosti A. The role of vitamins and minerals in hair loss: a review. Dermatology and Therapy. 2019;9(1):51-70.

    View paper (opens in a new tab)
  6. Guo EL, Katta R. Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatology Practical & Conceptual. 2017;7(1):1-10.

    View paper (opens in a new tab)
  7. Chandrasekhar K, Kapoor J, Anishetty S. A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults. Indian Journal of Psychological Medicine. 2012;34(3):255-262.

    View paper (opens in a new tab)
  8. Norwegian Scientific Committee for Food Safety (VKM). Risk assessment of "other substances": L-cysteine and L-cystine. Opinion of the Panel on Nutrition, Dietetic Products, Novel Food and Allergy. 2016.

    View VKM publications (opens in a new tab)

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