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Iron Beard

4.0
★ ★ ★ ★ ★
(1720 ratings)
Biotin 5000 mcg
Zinc 15 mg
Vitamin B5 100 mg
Folate 200 mcg
Collagen 200 mg
Product Image
Score59
A high-biotin, zinc, and pantothenic-acid formula with good nail alignment. The collagen amount is small, and the opaque complex adds uncertainty.
How scoring works
Capsule
Quantity:60 Capsule(s) • (30 servings)
Goals:
Nail Health
Hair Health

Score 59

A high-biotin, zinc, and pantothenic-acid formula with good nail alignment. The collagen amount is small, and the opaque complex adds uncertainty.
How scoring works
$23.39($0.77 per serving)
Vitacost
$ 23.39
iHerb
$ 23.39
Pure Formulas
$ 23.39
Amazon
$ 23.39
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Analysis

Biotin, zinc citrate, pantothenic acid, and vitamin C provide a practical beauty-nutrient base. Nail support is the clearest fit, while hair and skin benefits depend partly on whether the user has a nutritional gap.

Collagen hydrolysate is present at only a small amount compared with dedicated collagen products. MSM and the Iron Beard Complex add breadth, but the complex does not disclose individual ingredients or amounts.

Preformed vitamin A is substantial enough to matter and requires more care than beta-carotene. Claims related to digestion or testosterone are much less supported than the core hair-and-nail positioning.

Who is it for
  • Adults focused on nail support
  • People seeking high-dose biotin with zinc
  • Users who prefer capsules over gummies
Best for
  • Biotin supplementation
  • Nail-focused nutrition
  • Broad hair-support nutrient coverage

Pros

  • High biotin amount
  • Uses zinc citrate
  • Includes vitamin C and pantothenic acid

Cons

  • Very small collagen amount
  • Iron Beard Complex is not itemized
  • Weak support for digestive and testosterone goals

Warnings

  • High-dose biotin can interfere with thyroid, hormone, and cardiac laboratory tests; stop it as directed before testing.
  • Preformed vitamin A requires care during pregnancy and when combined with other retinol supplements.
  • Fifteen milligrams of zinc without listed copper may be poorly balanced for long-term use alongside other zinc products.

Nutrient quality

52 Moderate impact

Zinc citrate is useful, while folic acid, cyanocobalamin, and several unspecified forms are basic choices. Biotin and pantothenic acid are high, while collagen is far below a meaningful structural amount.

Ingredient transparency

60 Moderate impact

Most vitamins and minerals have amounts, while the beard complex does not disclose its components. The proprietary complex hides the doses of its individual ingredients.

Customer satisfaction

70 High impact

The average rating is mixed and weakens the customer signal. A large review base adds reliability, but no specific complaint or experience themes were provided.

Value for money

56 Moderate impact

The serving cost is moderate, but low collagen and an opaque complex reduce the formula quality received. Comparable products may offer clearer dosing or better quality for the cost.

Report analysis

Goals

Nail Health
Nail Health
Impact
High effect
B+ Goal FitB- Strength of SupportB+ CoverageB- Formula Quality
Collagen · 200 mgBiotin · 5000 mcg

Biotin, zinc, MSM, vitamin C, and collagen address keratin synthesis, sulfur supply, and structural support. The high biotin and useful zinc amounts provide the strongest nail contributions.

Collagen is present only at a token amount and the botanical blend is proprietary. The high biotin amount can distort thyroid, cardiac, and other laboratory tests and should be disclosed before blood work.

Study evidence
Biotin Supportive 8 studies
Collagen Supportive 4 studies
Vitamin C Supportive 1 study
Zinc No effect 1 study
Hair Health
Hair Health
Impact
High effect
B Goal FitC Strength of SupportC+ CoverageC Formula Quality
Biotin · 5000 mcgVitamin D · 2.5 mcgZinc · 15 mgVitamin C · 100 mgCollagen · 200 mg

High-dose biotin, zinc, vitamin C, and MSM support keratin metabolism, follicle nutrition, and connective tissue. Hydrolyzed collagen adds a relevant structural ingredient, but its amount is far below typical gram-level servings.

The broad formula reaches several pathways, although the proprietary beard blend and weak collagen dose reduce confidence in meaningful depth. Biotin can interfere with thyroid, hormone, and cardiac laboratory tests, so use should be disclosed before blood work.

Study evidence
Biotin Supportive 4 studies
Collagen Supportive 3 studies
Vitamin C Mixed 5 studies
Zinc Supportive 22 studies
Immunity
Immunity
Impact
Moderate effect
C+ Goal FitB- Strength of SupportC- CoverageC Formula Quality
Vitamin C · 100 mgZinc · 15 mgVitamin A · 1800 mcgVitamin D · 2.5 mcg

Zinc citrate and vitamin A provide some immune support, but the formula is built mainly for hair and beard goals. Vitamin C and vitamin D are present below stronger targeted immune amounts.

The zinc form is useful and clearly dosed, while the proprietary botanical complex hides its internal amounts. High biotin and beauty-focused ingredients add little to immune readiness.

Study evidence
Vitamin A Supportive 107 studies
Vitamin C Supportive 53 studies
Vitamin D Supportive 85 studies
Zinc Supportive 73 studies
General Health
General Health
Impact
Moderate effect
C+ Goal FitC- Strength of SupportC- CoverageC Formula Quality
Folate · 200 mcgVitamin B12 · 20 mcgVitamin D · 2.5 mcgCollagen · 200 mgZinc · 15 mgVitamin C · 100 mg

Vitamins and zinc provide basic nutritional support, but the beard and hair focus is narrower than general health. Evidence is established for the essential nutrients, while the tiny collagen amount and proprietary botanical complex provide weaker support.

Zinc at 15 mg is useful, but vitamin D is low, folic acid is modest, and 200 mg collagen is far below typical collagen servings. Zinc citrate and exact vitamin amounts aid assessment, while folic acid, cyanocobalamin, and an opaque botanical blend reduce form quality.

Study evidence
Collagen Supportive 31 studies
Folate Supportive 80 studies
Vitamin D Supportive 115 studies
Zinc Supportive 60 studies
Skin Health
Skin Health
Impact
Moderate effect
B- Goal FitD Strength of SupportC CoverageD Formula Quality
Zinc · 15 mgVitamin C · 100 mgCollagen · 200 mg

Vitamin C, zinc, vitamin A, MSM, and collagen cover several skin-support pathways. The collagen hydrolysate amount is far below the gram-level amounts commonly used for skin hydration and elasticity.

High-dose biotin mainly helps deficiency and can interfere with thyroid, hormone, and cardiac laboratory tests. A large proprietary beard blend and many B vitamins add complexity without proving stronger skin support.

Study evidence
Biotin Supportive 10 studies
Collagen Supportive 62 studies
Vitamin A Supportive 106 studies
Vitamin C Supportive 53 studies
Zinc Supportive 66 studies

Ingredients

IngredientAmount per serving
Vitamin A (Retinyl Palmitate)
 1800 mcg
Vitamin C (Ascorbic Acid)
 100 mg
Vitamin D3 (Cholecalciferol)
 2.5 mcg
Thiamine (Thiamine Hydrochloride)
 5 mg
Riboflavin
5 mg
Niacin (Niacinamide)
 5 mg
Vitamin B6 (Pyridoxine Hydrochloride)
 5 mg
Folic Acid
200 mcg
Vitamin B12 (Cyanocobalamin)
 20 mcg
Biotin
5000 mcg
Pantothenic Acid (Calcium D-Pantothenate)
 100 mg
Zinc (Zinc Citrate)
 15 mg
MSM
400 mg
Collagen Hydrolysate
200 mg
Iron Beard Complex
300 mg
Gluten Free Men 18–50 Dairy Free
Report overview
Biotin · 5000 mcg OverallScore85
B+ Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyC Value

Biotin is supplied at 5,000 mcg, matching the high-potency range used for hair and nail support. The broader formula adds co-factors, while the exact biotin amount remains clearly disclosed. High-dose biotin can interfere with some laboratory tests, so users should disclose use before blood testing.

View ingredientView products
Zinc (Zinc Citrate) · 15 mg OverallScore75
B+ Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyF Value
Citrate provides a useful, generally well-tolerated zinc form at a maintenance-focused dose. Vegetable capsules support rapid dissolution and avoid the filler burden of hard-pressed tablets. Cost efficiency is weak for the zinc delivered, so the broader hair-support formula must provide the main value.
View ingredientView products
Vitamin B5 (Calcium D-Pantothenate) · 100 mg OverallScore69
A- Active Ingredient Quality & BioavailabilityB Dose, Safety & Label TransparencyF Value

The formula uses a well-absorbed calcium pantothenate form and clearly discloses a meaningful maintenance dose. Its broad blend may suit people seeking combined hair and nutrient support, but it is inefficient when judged only by vitamin B5 delivery. The high biotin content may interfere with certain laboratory tests.

View ingredientView products
Loading alternative details
88 Performance

High Potency Maxi-Collagen 7000

Country Life
<p>Gram-level hydrolyzed collagen and branded collagen peptides provide much stronger structural-protein depth than the original’s very low collagen amount. Vitamin C and biotin complement the focused formula, though biotin can interfere with some laboratory tests.</p>
84 Performance

Hair Collagen + Keratin

youtheory
<p>Meaningfully dosed hydrolyzed collagen, keratin, and biotin provide stronger structural support than the original’s low collagen and opaque complex. High biotin can distort laboratory tests, and the large tablet serving reduces convenience.</p>
81 Performance

Skin Nails & Hair 2

MegaFood
<p>Nettle, zinc, biotin, active vitamin B6, natural vitamin E, and vitamin C form a coherent hair, skin, and nail blend without the original’s low-dose collagen claim. Duplicated form entries and uncertain benefit without a nutrient shortfall temper expectations.</p>
72 Budget

Liquid Collagen Complex Healthy Hair Skin & Nails Delicious Grape Flavor

RejuviCare
<p>Biotin and pantothenic acid preserve the beauty-nutrient focus at a lower serving cost. Collagen is far below common gram-level servings, but the simpler liquid avoids the original’s opaque proprietary complex.</p>
76 Budget

Collagen 1500 + C

Mason Natural
<p>Hydrolyzed bovine collagen, vitamin C, and biotin provide a more focused beauty formula at a lower serving cost. Collagen remains modest and high biotin may interfere with laboratory tests, while the multi-capsule serving reduces convenience.</p>
76 Budget

Sublingual Liquid B-12 2000 mcg with B-Complex

Solgar
<p>A broad liquid B-complex provides meaningful biotin and pantothenic-acid coverage at a lower serving cost. It lacks collagen and zinc, while conventional B-vitamin forms make it a partial rather than direct hair-support replacement.</p>
76 Value

Collagen

youtheory men
<p>Meaningful hydrolyzed collagen and vitamin C provide stronger structural support at a lower serving cost. Added fo-ti creates a liver-safety concern, so the economical formula is not an uncomplicated routine choice.</p>
73 Value

Alive! Hair Skin & Nails Gummies Delicious Strawberry Flavored

Nature's Way
<p>Vitamin C, biotin, and zinc provide practical hair and nail nutrition at accessible value. Collagen and silica are small, while carbohydrate and a hidden produce blend limit density.</p>
68 Value

Ultra B-12

NOW
<p>Methylcobalamin, dibencozide, biotin, and pantothenic acid provide low-cost B-vitamin support. Repeated entries imply extremely high exposure and weaken label clarity, while collagen and zinc are absent.</p>
Report alternatives

Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. The Role of Sesbania grandiflora-Derived Biotin and Bambusa arundinacea-Derived Silica Extracts in Promoting Hair, Skin, and Nail Health: A Randomized, Double-Blind, Placebo-Controlled Clinical Study.
    Patel MN; Maheshvari J; Patel N · Cureus · 2025
    Randomized trial105 participantsSkin Health Hair Health Nail Health forBiotin
  2. Interventions for infantile seborrhoeic dermatitis (including cradle cap).
    Victoire A; Magin P; Coughlan J; van Driel ML · The Cochrane database of systematic reviews · 2019
    Systematic review35 participants2 studies pooledSkin Health forBiotin
  3. Dexpanthenol enhances skin barrier repair and reduces inflammation after sodium lauryl sulphate-induced irritation.
    Proksch E; Nissen HP · The Journal of dermatological treatment · 2009
    Randomized trialSkin Health forVitamin B5
  4. Panthenol Allergic Contact Dermatitis: Sources of Exposure, Reported Cases, and a Call for More Frequent Testing.
    Weber B; Hylwa S · Dermatitis : contact, atopic, occupational, drug · 2025
    Narrative reviewSkin Health forVitamin B5
  5. Effects of Zinc Supplementation on Inflammatory Skin Diseases: A Systematic Review of the Clinical Evidence.
    Dhaliwal S; Nguyen M; Vaughn AR; Notay M; Chambers CJ; Sivamani RK · American journal of clinical dermatology · 2020
    Systematic review22 studies pooledSkin Health forZinc
  6. Skin changes induced by a zinc oxide dressing compared with a hydrocolloid dressing in healthy individuals.
    Nielsen LF; Blume N; Romme T; Samuelsen P; Everland H; Ifversen P; Karlsmark T · Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI) · 2005
    Non-randomized trial11 participantsSkin Health forZinc
  7. The effects of minoxidil, 1% pyrithione zinc and a combination of both on hair density: a randomized controlled trial.
    Berger RS; Fu JL; Smiles KA; Turner CB; Schnell BM; Werchowski KM; Lammers KM · The British journal of dermatology · 2003
    Randomized trial200 participantsHair Health forZinc
  8. Hair Loss and Zinc Deficiency: A Cross-Sectional Study.
    Liran O; Vered S; Cohen B; Shapiro Ben David S; Nakhleh A; Rahamim-Cohen D; Azuri J; Adler L · Healthcare (Basel, Switzerland) · 2025
    Cross-sectional study23,975 participantsHair Health forZinc
  9. Low-Molecular-Weight Collagen Peptide Supplementation Improves Cellulite Severity, Skin Elasticity, and Hair Shaft Diameter: A Clinical Study with Pharmacokinetic Evaluation.
    Hwang S; Won J; Kim S; Kang W; Park M · Journal of medicinal food · 2026
    Randomized trial114 participantsHair Health forCollagen
  10. Dietary Collagen Supplementation as a Strategy for Skin Health: A Narrative Review of Clinical Effects on Skin, Hair, Nails, and Wound Healing.
    Biełach-Bazyluk A; Jurga M; Flisiak I; Zbroch E · Nutrients · 2026
    Narrative reviewHair Health forCollagen
  11. Vitamins and minerals: their role in nail health and disease.
    Scheinfeld N; Dahdah MJ; Scher R · Journal of drugs in dermatology : JDD · 2007
    Narrative reviewNail Health forBiotin Nail Health forZinc
  12. Biotin for the treatment of nail disease: what is the evidence?
    Lipner SR; Scher RK · The Journal of dermatological treatment · 2018
    Narrative reviewNail Health forBiotin
  13. The Infatuation With Biotin Supplementation: Is There Truth Behind Its Rising Popularity? A Comparative Analysis of Clinical Efficacy versus Social Popularity.
    Soleymani T; Lo Sicco K; Shapiro J · Journal of drugs in dermatology : JDD · 2018
    Narrative reviewHair Health forBiotin
  14. A double-blind, placebo-controlled, randomised, clinical study on the effectiveness of collagen peptide on osteoarthritis.
    Kumar S; Sugihara F; Suzuki K; Inoue N; Venkateswarathirukumara S · Journal of the science of food and agriculture · 2015
    Randomized trialGeneral Health forCollagen
  15. Efficacy and safety of native type II collagen in modulating knee osteoarthritis symptoms: a randomised, double-blind, placebo-controlled trial.
    Luo C; Su W; Song Y; Srivastava S · Journal of experimental orthopaedics · 2023
    Randomized trial101 participantsGeneral Health forCollagen
  16. Healing Process, Pain, and Health-Related Quality of Life in Patients with Venous Leg Ulcers Treated with Fish Collagen Gel: A 12-Week Randomized Single-Center Study.
    Mościcka P; Cwajda-Białasik J; Szewczyk MT; Jawień A · International journal of environmental research and public health · 2022
    Randomized trial100 participantsGeneral Health forCollagen
  17. Efficacy and Safety of Dietary Undenatured Type II Collagen on Joint and Motor Function in Healthy Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study.
    Shiojima Y; Takahashi M; Takahashi R; Maruyama K; Moriyama H; Bagchi D; Bagchi M; Akanuma M · Journal of the American Nutrition Association · 2023
    Randomized trial64 participantsGeneral Health forCollagen
  18. The use of a collagen matrix in hard-to-heal venous leg ulcers.
    Romanelli M; Mulder G; Paggi B; Macchia M; Panduri S; Dini V · Journal of wound care · 2016
    Randomized trial40 participantsGeneral Health forCollagen
  19. Intakes of Folate, Vitamin B6, and Vitamin B12 in Relation to All-Cause and Cause-Specific Mortality: A National Population-Based Cohort.
    Bo Y; Xu H; Zhang H; Zhang J; Wan Z; Zhao X; Yu Z · Nutrients · 2022
    Cohort study55,569 participantsGeneral Health forFolate
  20. The responsiveness of plasma homocysteine to small increases in dietary folic acid: a primary care study.
    Schorah CJ; Devitt H; Lucock M; Dowell AC · European journal of clinical nutrition · 1998
    Randomized trial119 participantsGeneral Health forFolate
  21. Associations of Serum Folate and Homocysteine Concentrations with All-Cause, Cardiovascular Disease, and Cancer Mortality in Men and Women in Korea: the Cardiovascular Disease Association Study.
    Song S; Song BM; Park HY · The Journal of nutrition · 2023
    Cohort study21,260 participantsGeneral Health forFolate
  22. The concept of folic acid supplementation and its role in prevention of neural tube defect among pregnant women: PRISMA.
    Seyoum Tola F · Medicine · 2024
    Systematic reviewGeneral Health forFolate
  23. Systematic review of adverse health outcomes associated with high serum or red blood cell folate concentrations.
    Colapinto CK; O'Connor DL; Sampson M; Williams B; Tremblay MS · Journal of public health (Oxford, England) · 2017
    Systematic review71,847 participants46 studies pooledGeneral Health forFolate
  24. Vitamin D supplementation for prevention of mortality in adults.
    Bjelakovic G; Gluud LL; Nikolova D; Whitfield K; Wetterslev J; Simonetti RG; Bjelakovic M; Gluud C · The Cochrane database of systematic reviews · 2014
    Meta-analysis95,286 participants159 studies pooledGeneral Health forVitamin D
  25. Effect of vitamin D on gastrointestinal symptoms and health-related quality of life in irritable bowel syndrome patients: a randomized double-blind clinical trial.
    Abbasnezhad A; Amani R; Hajiani E; Alavinejad P; Cheraghian B; Ghadiri A · Neurogastroenterology and motility · 2018
    Randomized trial90 participantsGeneral Health forVitamin D
  26. The impact of vitamin D administration on mortality in COVID-19 patients: a systematic review and meta-analysis of randomized controlled trials.
    Kow CS; Ramachandram DS; Hasan SS; Wong Z; Thiruchelvam K · Inflammopharmacology · 2024
    Meta-analysis2,495 participants19 studies pooledGeneral Health forVitamin D
  27. Vitamin D Status and Mortality: A Systematic Review of Observational Studies.
    Heath AK; Kim IY; Hodge AM; English DR; Muller DC · International journal of environmental research and public health · 2019
    Systematic review84 studies pooledGeneral Health forVitamin D
  28. Meta-analysis of long-term vitamin D supplementation on overall mortality.
    Zheng Y; Zhu J; Zhou M; Cui L; Yao W; Liu Y · PloS one · 2014
    Meta-analysis42 studies pooledGeneral Health forVitamin D
  29. Effectiveness of sodium bicarbonate and zinc chloride mouthwashes in the treatment of oral mucositis and quality of life in patients with cancer under chemotherapy.
    Mohammadi F; Oshvandi K; Kamallan SR; Khazaei S; Ranjbar H; Ahmadi-Motamayel F; Gillespie M; Jenabi E; Vafaei SY · Nursing open · 2022
    Randomized trial144 participantsGeneral Health forZinc
  30. Zinc supplementation in young children with acute diarrhea in India.
    Sazawal S; Black RE; Bhan MK; Bhandari N; Sinha A; Jalla S · The New England journal of medicine · 1995
    Randomized trial937 participantsGeneral Health forZinc
  31. Associations of mortality with ocular disorders and an intervention of high-dose antioxidants and zinc in the Age-Related Eye Disease Study: AREDS Report No. 13.
    Clemons TE; Kurinij N; Sperduto RD; AREDS Research Group · Archives of ophthalmology (Chicago, Ill. : 1960) · 2004
    Randomized trial4,753 participantsGeneral Health forZinc
  32. Effects of zinc and probiotic co-supplementation on inflammation, gastrointestinal symptoms, quality of life, and mood in irritable bowel syndrome patients.
    Rezazadegan M; Soheilipour M; Amani R · Scientific reports · 2026
    Randomized trial84 participantsGeneral Health forZinc
  33. Effect of zinc sulfate supplementation on premenstrual syndrome and health-related quality of life: Clinical randomized controlled trial.
    Siahbazi S; Behboudi-Gandevani S; Moghaddam-Banaem L; Montazeri A · The journal of obstetrics and gynaecology research · 2018
    Randomized trial142 participantsGeneral Health forZinc
  34. Low serum biotinidase activity in children with valproic acid monotherapy.
    Schulpis KH; Karikas GA; Tjamouranis J; Regoutas S; Tsakiris S · Epilepsia · 2001
    Clinical trial125 participantsHair Health Skin Health forBiotin
  35. Vitamins A, B, C, and D: A Short Review for the Dermatologist.
    Coerdt KM; Goggins CA; Khachemoune A · Alternative therapies in health and medicine · 2021
    Narrative reviewHair Health forBiotin
  36. Calcium and Vitamin D Supplementation with and Without Collagen on Bone Density and Skin Elasticity in Menopausal Women-A Randomized Controlled Study.
    Duangjai A; Srivilai J; Nangola S; Amornlerdpison D · Clinics and practice · 2025
    Randomized trialHair Health forCollagen
  37. Management of hair loss associated with endocrine therapy in patients with breast cancer: an overview.
    Karatas F; Sahin S; Sever AR; Altundag K · SpringerPlus · 2016
    Narrative reviewHair Health forVitamin C
  38. Elucidating causal relationships of diet-derived circulating antioxidants and the risk of non-scarring alopecia: A Mendelian randomization study.
    Ba Y; Shen L; Peng X; Zhang Y; Wang J · Medicine · 2024
    Methods validation study201,019 participantsHair Health forVitamin C
  39. Alterations of plasma antioxidants and mitochondrial DNA mutation in hair follicles of smokers.
    Liu CS; Chen HW; Lii CK; Tsai CS; Kuo CL; Wei YH · Environmental and molecular mutagenesis · 2002
    Observational studyHair Health forVitamin C
  40. Removal of synthetic hair dye using formamidine sulfinic acid and other sulfinate precursors.
    Hawkes JA; Lewis DM; Mama J; Murray J · International journal of cosmetic science · 2026
    Methods validation studyHair Health forVitamin C
  41. A Zinc Sulphate-Resistant Acrodermatitis Enteropathica Patient with a Novel Mutation in SLC39A4 Gene.
    Kilic M; Taskesen M; Coskun T; Gürakan F; Tokatli A; Sivri HS; Dursun A; Schmitt S; Küry S · JIMD reports · 2013
    Case reportHair Health forVitamin C
  42. Incubatory environment of the scalp impacts pre-emergent hair to affect post-emergent hair cuticle integrity.
    Schwartz JR; Henry JP; Kerr KM; Flagler MJ; Page SH; Redman-Furey N · Journal of cosmetic dermatology · 2018
    Randomized trialHair Health forZinc
  43. A comparison of hair quality and cosmetic acceptance following the use of two anti-dandruff shampoos.
    Draelos ZD; Kenneally DC; Hodges LT; Billhimer W; Copas M; Margraf C · The journal of investigative dermatology. Symposium proceedings · 2006
    Randomized trial40 participantsHair Health forZinc
  44. BMI and levels of zinc, copper in hair, serum and urine of Turkish male patients with androgenetic alopecia.
    Ozturk P; Kurutas E; Ataseven A; Dokur N; Gumusalan Y; Gorur A; Tamer L; Inaloz S · Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS) · 2015
    Case-control study216 participantsHair Health forZinc
  45. Analysis of serum zinc and copper concentrations in hair loss.
    Kil MS; Kim CW; Kim SS · Annals of dermatology · 2013
    Case-control study342 participantsHair Health forZinc
  46. Depressed immune response to tetanus in children with vitamin A deficiency.
    Semba RD; Muhilal; Scott AL; Natadisastra G; Wirasasmita S; Mele L; Ridwan E; West KP; Sommer A · The Journal of nutrition · 1992
    Randomized trial236 participantsImmunity forVitamin A
  47. Impact of a single megadose of vitamin A at delivery on breastmilk of mothers and morbidity of their infants.
    Roy SK; Islam A; Molla A; Akramuzzaman SM; Jahan F; Fuchs G · European journal of clinical nutrition · 1997
    Randomized trial50 participantsImmunity forVitamin A
  48. Vitamin A supplementation reduces measles morbidity in young African children: a randomized, placebo-controlled, double-blind trial.
    Coutsoudis A; Broughton M; Coovadia HM · The American journal of clinical nutrition · 1991
    Randomized trial60 participantsImmunity forVitamin A
  49. Vitamin A supplementation enhances specific IgG antibody levels and total lymphocyte numbers while improving morbidity in measles.
    Coutsoudis A; Kiepiela P; Coovadia HM; Broughton M · The Pediatric infectious disease journal · 1992
    Randomized trial60 participantsImmunity forVitamin A
  50. Vitamin A supplementation reduces the monocyte chemoattractant protein-1 intestinal immune response of Mexican children.
    Long KZ; Santos JI; Estrada Garcia T; Haas M; Firestone M; Bhagwat J; Dupont HL; Hertzmark E; Rosado JL; Nanthakumar NN · The Journal of nutrition · 2006
    Randomized trial127 participantsImmunity forVitamin A
  51. Vitamin C and contribution to the normal function of the immune system: evaluation of a health claim pursuant to Article 14 of Regulation (EC) No 1924/2006.
    EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) · EFSA journal. European Food Safety Authority · 2026
    Guideline / consensusImmunity forVitamin C
  52. Therapeutic effects of high-dose vitamin C supplementation in patients with COVID-19: a meta-analysis.
    Sun L; Zhao JH; Fan WY; Feng B; Liu WW; Chen RQ; Ban C; Dang AG; Wang M; Luo KT; Zhou GY; Yu FF; Ba Y · Nutrition reviews · 2024
    Meta-analysis2,334 participants14 studies pooledImmunity forVitamin C
  53. Effect of micronutrient supplements on influenza and other respiratory tract infections among adults: a systematic review and meta-analysis.
    Abioye AI; Bromage S; Fawzi W · BMJ global health · 2021
    Meta-analysisImmunity forVitamin C
  54. New evidence for antioxidant properties of vitamin C.
    Vojdani A; Bazargan M; Vojdani E; Wright J · Cancer detection and prevention · 2001
    Randomized trial20 participantsImmunity forVitamin C
  55. Enhanced Vitamin C Delivery: A Systematic Literature Review Assessing the Efficacy and Safety of Alternative Supplement Forms in Healthy Adults.
    Calder PC; Kreider RB; McKay DL · Nutrients · 2025
    Systematic review13 studies pooledImmunity forVitamin C
  56. Vitamin D supplementation to prevent acute respiratory infections: individual participant data meta-analysis.
    Martineau AR; Jolliffe DA; Greenberg L; Aloia JF; Bergman P; Dubnov-Raz G; Esposito S; Ganmaa D; Ginde AA; Goodall EC; Grant CC; Janssens W; Jensen ME; Kerley CP; Laaksi I; Manaseki-Holland S; Mauger D; Murdoch DR; Neale R; Rees JR; Simpson S; Stelmach I; Trilok Kumar G; Urashima M; Camargo CA; Griffiths CJ; Hooper RL · Health technology assessment (Winchester, England) · 2020
    Meta-analysis11,321 participants25 studies pooledImmunity forVitamin D
  57. Association Between Vitamin D and Influenza: Meta-Analysis and Systematic Review of Randomized Controlled Trials.
    Zhu Z; Zhu X; Gu L; Zhan Y; Chen L; Li X · Frontiers in nutrition · 2022
    Meta-analysis4,859 participants10 studies pooledImmunity forVitamin D
  58. Vitamin D3 and deconvoluting a rash.
    Ernst MK; Evans ST; Techner JM; Rothbaum RM; Christensen LF; Onay UV; Biyashev D; Demczuk MM; Nguyen CV; Honda KS; McCormick TS; Tsoi LC; Gudjonsson JE; Cooper KD; Lu KQ · JCI insight · 2023
    Randomized trial28 participantsImmunity forVitamin D
  59. Effect of vitamin D3 supplementation on cellular immunity and inflammatory markers in COVID-19 patients admitted to the ICU.
    Bychinin MV; Klypa TV; Mandel IA; Yusubalieva GM; Baklaushev VP; Kolyshkina NA; Troitsky AV · Scientific reports · 2022
    Randomized trial110 participantsImmunity forVitamin D
  60. Current opinion on the role of vitamin D supplementation in respiratory infections and asthma/COPD exacerbations: A need to establish publication guidelines for overcoming the unpublished data.
    Anitua E; Tierno R; Alkhraisat MH · Clinical nutrition (Edinburgh, Scotland) · 2022
    Meta-analysis50,554 participants65 studies pooledImmunity forVitamin D
  61. Nutrient supplementation for prevention of viral respiratory tract infections in healthy subjects: A systematic review and meta-analysis.
    Vlieg-Boerstra B; de Jong N; Meyer R; Agostoni C; De Cosmi V; Grimshaw K; Milani GP; Muraro A; Oude Elberink H; Pali-Schöll I; Roduit C; Sasaki M; Skypala I; Sokolowska M; van Splunter M; Untersmayr E; Venter C; O'Mahony L; Nwaru BI · Allergy · 2022
    Meta-analysis199,055 participants115 studies pooledImmunity forZinc
  62. Zinc supplementation reduces the incidence of acute lower respiratory infections in infants and preschool children: a double-blind, controlled trial.
    Sazawal S; Black RE; Jalla S; Mazumdar S; Sinha A; Bhan MK · Pediatrics · 1998
    Randomized trial609 participantsImmunity forZinc
  63. A randomized controlled trial of zinc supplementation in the treatment of acute respiratory tract infection in Thai children.
    Rerksuppaphol S; Rerksuppaphol L · Pediatric reports · 2020
    Randomized trial64 participantsImmunity forZinc
  64. The effect of zinc and vitamin A supplementation on immune response in an older population.
    Fortes C; Forastiere F; Agabiti N; Fano V; Pacifici R; Virgili F; Piras G; Guidi L; Bartoloni C; Tricerri A; Zuccaro P; Ebrahim S; Perucci CA · Journal of the American Geriatrics Society · 1998
    Randomized trial136 participantsImmunity forZinc
  65. The role of specific nutrients in preventing immune system and blood cell disorders: an umbrella review.
    Vecchietti A; Strano P; Minutolo G; Grieco V; Cappuccio G; Granvillano G; Confalonieri L; Briganti GL; Raso E; Chimienti M; Pellegrini M; Mercogliano M; Spatari G; Lugli C; Urbano T; Lorenzon A · Journal of preventive medicine and hygiene · 2026
    Systematic review13 studies pooledImmunity forZinc
  66. Treatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopy.
    Colombo VE; Gerber F; Bronhofer M; Floersheim GL · Journal of the American Academy of Dermatology · 1991
    Other32 participantsNail Health forBiotin
  67. Treatment of brittle nail with a hydroxypropyl chitosan-based lacquer, alone or in combination with oral biotin: A randomized, assessor-blinded trial.
    Chiavetta A; Mazzurco S; Secolo MP; Tomarchio G; Milani M · Dermatologic therapy · 2020
    Randomized trial50 participantsNail Health forBiotin
  68. Oral supplementation with specific bioactive collagen peptides improves nail growth and reduces symptoms of brittle nails.
    Hexsel D; Zague V; Schunck M; Siega C; Camozzato FO; Oesser S · Journal of cosmetic dermatology · 2018
    Single-arm trial25 participantsNail Health forCollagen
  69. Influence of collagen peptide supplementation on visible signs of skin and nail health and -aging in an East Asian population: A double blind, randomized, placebo-controlled trial.
    Vleminckx S; Virgilio N; Asserin J; Prawitt J; Silva CIF · Journal of cosmetic dermatology · 2024
    Randomized trial85 participantsNail Health forCollagen
  70. Nail Supplements: When, How, and Why?
    Zaraa I; Richert B · Skin appendage disorders · 2026
    Narrative reviewNail Health forCollagen
  71. Expanding the COL7A1 mutation database: novel and recurrent mutations and unusual genotype-phenotype constellations in 41 patients with dystrophic epidermolysis bullosa.
    Kern JS; Kohlhase J; Bruckner-Tuderman L; Has C · The Journal of investigative dermatology · 2006
    Observational study41 participantsNail Health forCollagen
  72. Vitamin C Deficiency in Inflammatory Bowel Disease: The Forgotten Micronutrient.
    Dunleavy KA; Ungaro RC; Manning L; Gold S; Novak J; Colombel JF · Crohn's & colitis 360 · 2023
    Other20 participantsNail Health forVitamin C
  73. Evaluation of biophysical skin parameters and hair changes in patients with acne vulgaris treated with isotretinoin, and the effect of biotin use on these parameters.
    Aksac SE; Bilgili SG; Yavuz GO; Yavuz IH; Aksac M; Karadag AS · International journal of dermatology · 2021
    Non-randomized trial60 participantsSkin Health forBiotin
  74. Generalized seborrhoeic dermatitis. Clinical and therapeutic data of 25 patients.
    Messaritakis J; Kattamis C; Karabula C; Matsaniotis N · Archives of disease in childhood · 1976
    Non-randomized trial25 participantsSkin Health forBiotin
  75. Holocarboxylase synthetase deficiency: novel clinical and molecular findings.
    Tammachote R; Janklat S; Tongkobpetch S; Suphapeetiporn K; Shotelersuk V · Clinical genetics · 2010
    Case series4 participantsSkin Health forBiotin
  76. Exploring the Impact of Hydrolyzed Collagen Oral Supplementation on Skin Rejuvenation: A Systematic Review and Meta-Analysis.
    Dewi DAR; Arimuko A; Norawati L; Yenny SW; Setiasih NL; Perdiyana A; Arkania N; Nadhira F; Wiliantari N · Cureus · 2024
    Meta-analysis967 participants14 studies pooledSkin Health forCollagen
  77. Effects of collagen-based supplements on skin's hydration and elasticity: A systematic review and meta-analysis.
    Danessa G; Notario D; Regina R · Indian journal of dermatology, venereology and leprology · 2025
    Meta-analysis646 participants10 studies pooledSkin Health forCollagen
  78. Oral intake of collagen peptide NS improves hydration, elasticity, desquamation, and wrinkling in human skin: a randomized, double-blinded, placebo-controlled study.
    Lee M; Kim E; Ahn H; Son S; Lee H · Food & function · 2023
    Randomized trial100 participantsSkin Health forCollagen
  79. Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study.
    Kim DU; Chung HC; Choi J; Sakai Y; Lee BY · Nutrients · 2018
    Randomized trial64 participantsSkin Health forCollagen
  80. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis.
    de Miranda RB; Weimer P; Rossi RC · International journal of dermatology · 2021
    Meta-analysis1,125 participants19 studies pooledSkin Health forCollagen
  81. Efficacy and Tolerability of Topical 0.1% Stabilized Bioactive Retinol for Photoaging: A Vehicle-Controlled Integrated Analysis.
    Farris P; Berson D; Bhatia N; Goldberg D; Lain E; Mariwalla K; Zeichner J; Miller D; McGuire T; Kizoulis M · Journal of drugs in dermatology : JDD · 2024
    Meta-analysis471 participants6 studies pooledSkin Health forVitamin A
  82. Tensile properties and contours of aging facial skin. A controlled double-blind comparative study of the effects of retinol, melibiose-lactose and their association.
    Piérard-Franchimont C; Castelli D; Cromphaut IV; Bertin C; Ries G; Cauwenbergh G; Piérard GE · Skin research and technology : official journal of International Society for Bioengineering and the Skin (ISBS) [and] International Society for Digital Imaging of Skin (ISDIS) [and] International Society for Skin Imaging (ISSI) · 2016
    Randomized trial120 participantsSkin Health forVitamin A
  83. Antiaging action of retinol: from molecular to clinical.
    Bellemère G; Stamatas GN; Bruère V; Bertin C; Issachar N; Oddos T · Skin pharmacology and physiology · 2009
    Randomized trial48 participantsSkin Health forVitamin A
  84. An Updated Review of Topical Tretinoin in Dermatology: From Acne and Photoaging to Skin Cancer.
    Balado-Simó P; Morgado-Carrasco D; Gómez-Armayones S; López-Ferrer A; Barco D; Ferrándiz-Pulido C; Podlipnik S · Journal of clinical medicine · 2025
    Narrative reviewSkin Health forVitamin A
  85. Novel Cyclized Hexapeptide-9 Outperforms Retinol Against Skin Aging: A Randomized, Double-Blinded, Active- and Vehicle-Controlled Clinical Trial.
    Chang H; Tao K; Yang Y; Wang Y; Ge M; Wang X; Tang S; Yu H · Journal of cosmetic dermatology · 2025
    Randomized trialSkin Health forVitamin A
  86. Evaluation of the anti-wrinkle effect of an ascorbic acid-loaded dissolving microneedle patch via a double-blind, placebo-controlled clinical study.
    Lee C; Yang H; Kim S; Kim M; Kang H; Kim N; An S; Koh J; Jung H · International journal of cosmetic science · 2017
    Randomized trial23 participantsSkin Health forVitamin C
  87. Comparative Study on the Outcome of Periorbital Wrinkles Treated with Laser-Assisted Delivery of Vitamin C or Vitamin C Plus Growth Factors: A Randomized, Double-blind, Clinical Trial.
    Machado BHB; Frame J; Zhang J; Najlah M · Aesthetic plastic surgery · 2021
    Randomized trial149 participantsSkin Health forVitamin C
  88. Randomized trial of topical ascorbic acid in DMSO versus imiquimod for the treatment of basal cell carcinoma.
    Burke B; Bailie JE · Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie · 2022
    Randomized trial25 participantsSkin Health forVitamin C
  89. Vitamin C improves healing of foot ulcers: a randomised, double-blind, placebo-controlled trial.
    Gunton JE; Girgis CM; Lau T; Vicaretti M; Begg L; Flood V · The British journal of nutrition · 2022
    Randomized trial16 participantsSkin Health forVitamin C
  90. Dietary nutrient intakes and skin-aging appearance among middle-aged American women.
    Cosgrove MC; Franco OH; Granger SP; Murray PG; Mayes AE · The American journal of clinical nutrition · 2007
    Cross-sectional study4,025 participantsSkin Health forVitamin C
  91. Sex-related differences in response to zinc pyrithione shampoo vs. non-anti-dandruff shampoo.
    Collins LZ; Baines FL; Matheson JR; Turner GA; Diao Y; Li Y; Pi Y · International journal of cosmetic science · 2019
    Meta-analysis2,088 participants20 studies pooledSkin Health forZinc
  92. Maintenance of an Acidic Skin Surface with a Novel Zinc Lactobionate Emollient Preparation Improves Skin Barrier Function in Patients with Atopic Dermatitis.
    Andrew PV; Pinnock A; Poyner A; Brown K; Chittock J; Kay LJ; Cork MJ; Danby SG · Dermatology and therapy · 2024
    Cohort study23 participantsSkin Health forZinc
  93. Spatial expression of metallothionein, matrix metalloproteinase-1 and Ki-67 in human epidermal wounds treated with zinc and determined by quantitative immunohistochemistry: A randomised double-blind trial.
    Ågren MS; Chafranska L; Eriksen JO; Forman JL; Bjerrum MJ; Schjerling P; Larsen HF; Cottarelli E; Jorgensen LN; Gjerdrum LMR · European journal of cell biology · 2021
    Randomized trial30 participantsSkin Health forZinc
  94. A pilot trial using topical regular crystalline insulin vs. aqueous zinc solution for uncomplicated cutaneous wound healing: Impact on quality of life.
    Attia EA; Belal DM; El Samahy MH; El Hamamsy MH · Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society · 2014
    Randomized trial90 participantsSkin Health forZinc
  95. Evidence-Based Nutritional Interventions in Wound Care.
    Saeg F; Orazi R; Bowers GM; Janis JE · Plastic and reconstructive surgery · 2021
    Systematic review2,339 participants36 studies pooledSkin Health forZinc