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Hair Skin & Nails

Sundown
4.4
★ ★ ★ ★ ★
(6678 ratings)
Phosphorus 128 mg
Biotin 5000 mcg
Manganese 2 mg
Calcium 255 mg
PABA 10 mg
Niacin 25 mg
Choline 10 mg
Product Image
Score68
Best suited to nail health, with the clearest benefits coming from the disclosed active ingredients. Biotin, zinc, vitamin C, and supporting vitamins provide relevant nutritional coverage, but the collagen and botanical additions are far too small to offer meaningful structural support.
How scoring works
Quantity:120 Tablet(s) • (40 servings)
Goals:
Nail Health
Hair Health

Score 68

Best suited to nail health, with the clearest benefits coming from the disclosed active ingredients. Biotin, zinc, vitamin C, and supporting vitamins provide relevant nutritional coverage, but the collagen and botanical additions are far too small to offer meaningful structural support.
How scoring works
$11.27($0.28 per serving)
Amazon
$ 26.95
iHerb
$ 11.27
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Analysis

Biotin, zinc, vitamin C, and supporting vitamins provide relevant nutritional coverage, but the collagen and botanical additions are far too small to offer meaningful structural support. Mixed nutrient forms and several label duplications also reduce quality and transparency. The 5,000 mcg biotin amount can interfere with thyroid, hormone, and cardiac laboratory tests.

D-biotin directly supports keratin, while vitamin C, zinc, collagen, and horsetail add several nail-related pathways. Biotin has useful nail evidence, but most of the many supporting ingredients are too low to carry strong clinical support. D-biotin at 5,000 mcg is meaningful, while collagen at 50 mg and horsetail at 3 mg are token amounts.

The formula includes collagen, vitamin C, zinc, and antioxidants that could support several aspects of skin health. However, the collagen amount is only a trace, and high-dose biotin is mainly useful when intake is inadequate. The broad nutrient list creates more appearance of coverage than meaningful depth.

Who is it for
  • People seeking nail health support
  • People seeking hair health support
  • People seeking skin health support
Best for
  • Nail Health
  • Hair Health
  • Skin Health

Pros

  • The 5,000 mcg biotin amount can interfere with thyroid, hormone, and cardiac laboratory tests.
  • D-biotin directly supports keratin, while vitamin C, zinc, collagen, and horsetail add several nail-related pathways.
  • High-dose biotin can interfere with some blood tests, so the testing clinician should be told before laboratory work.
  • Biotin, zinc, vitamin D, vitamin C, and several antioxidants provide broad nutrient support for hair when dietary intake is low.
  • Many forms are basic and repeated entries make some totals harder to interpret.

Cons

  • Biotin, zinc, vitamin C, and supporting vitamins provide relevant nutritional coverage, but the collagen and botanical additions are far too small to offer meaningful structural support.
  • Mixed nutrient forms and several label duplications also reduce quality and transparency.
  • Biotin has useful nail evidence, but most of the many supporting ingredients are too low to carry strong clinical support.
  • D-biotin at 5,000 mcg is meaningful, while collagen at 50 mg and horsetail at 3 mg are token amounts.
  • D-biotin is well identified, though magnesium oxide and several basic vitamin or mineral forms reduce quality.

Warnings

  • The 5,000 mcg biotin amount can interfere with thyroid, hormone, and cardiac laboratory tests.
  • High-dose biotin can interfere with some blood tests, so the testing clinician should be told before laboratory work.
  • The 5,000 mcg biotin amount can interfere with thyroid, cardiac, hormone, and other laboratory tests, while preformed vitamin A warrants pregnancy caution.
  • The high biotin amount can interfere with some laboratory tests, so it should be disclosed before blood work.
  • The available facts support only a neutral value judgment; high-dose biotin can interfere with some laboratory tests, so the dose should be disclosed before blood work.

Nutrient quality

57 Moderate impact

D-biotin, vitamin D3, and zinc provide the strongest ingredient support. Basic mineral forms and many token-dose extras limit the formula.

Ingredient transparency

74 High impact

Most active amounts are stated clearly, and no proprietary blend is shown. Duplicate nutrient entries and missing excipient details make the full label harder to interpret.

Customer satisfaction

70 High impact

The supplied average rating is strong and comes from a large review base. No review text is available to assess recurring complaints or purpose-specific experiences.

Value for money

73 High impact

The low serving cost supports good value for the vitamin and biotin core. Token-dose extras and basic mineral forms keep the formula from standing out on quality.

Report analysis

Goals

Nail Health
Nail Health
Impact
High effect
B+ Goal FitC+ Strength of SupportB- CoverageD+ Formula Quality
Collagen · 50 mgBiotin · 5000 mcgHorsetail · 3 mg

D-biotin directly supports keratin, while vitamin C, zinc, collagen, and horsetail add several nail-related pathways. Biotin has useful nail evidence, but most of the many supporting ingredients are too low to carry strong clinical support.

D-biotin at 5,000 mcg is meaningful, while collagen at 50 mg and horsetail at 3 mg are token amounts. D-biotin is well identified, though magnesium oxide and several basic vitamin or mineral forms reduce quality. High-dose biotin can interfere with some blood tests, so the testing clinician should be told before laboratory work.

Study evidence
Biotin Supportive 8 studies
Collagen Supportive 4 studies
Horsetail Not classified

No linked studies yet.

Magnesium Not classified

No linked studies yet.

Vitamin C Supportive 1 study
Zinc No effect 1 study
Hair Health
Hair Health
Impact
Moderate effect
C+ Goal FitC- Strength of SupportC+ CoverageD- Formula Quality
Biotin · 5000 mcgVitamin D · 25 mcgZinc · 7.5 mgVitamin C · 60 mgCollagen · 50 mg

Biotin, zinc, vitamin D, vitamin C, and several antioxidants provide broad nutrient support for hair when dietary intake is low. The formula looks comprehensive, but its collagen, horsetail, amino-support, and antioxidant extras are mostly too small to contribute meaningfully.

Many forms are basic and repeated entries make some totals harder to interpret. The 5,000 mcg biotin amount can interfere with thyroid, cardiac, hormone, and other laboratory tests, while preformed vitamin A warrants pregnancy caution.

Study evidence
Biotin Supportive 4 studies
Collagen Supportive 3 studies
Horsetail Not classified

No linked studies yet.

Vitamin A Disputed 13 studies
Vitamin C Mixed 5 studies
Vitamin D Disputed 34 studies
Zinc Supportive 22 studies

Ingredients

IngredientAmount per serving
Vitamin A (Vitamin A Palmitate)
 1500 mcg
Vitamin C (Ascorbic Acid)
 60 mg
Vitamin D (Cholecalciferol, Vitamin D3)
 25 mcg
Vitamin E (DL-Alpha-Tocopheryl Acetate)
 6.7 mg
Thiamine (Thiamine Hydrochloride, Vitamin B1)
 5 mg
Riboflavin (Vitamin B2)
 5 mg
Niacin (Niacinamide)
 25 mg
Vitamin B6 (Pyridoxine Hydrochloride)
 5 mg
Folate
333 mcg DFE
Vitamin B12 (Cyanocobalamin)
 8 mcg
Biotin (D-Biotin)
 5000 mcg
Pantothenic Acid (D-Calcium Pantothenate)
 15 mg
Calcium (Calcium Carbonate, Dicalcium Phosphate)
 255 mg
Phosphorus (Dicalcium Phosphate)
 128 mg
Magnesium (Magnesium Oxide)
 50 mg
Zinc (Zinc Gluconate)
 7.5 mg
Manganese (Manganese Gluconate)
 2 mg
PABA
10 mg
Choline Bitartrate
10 mg
Inositol
30 mg
Ribonucleic Acid
10 mg
Citrus Bioflavonoid/Rutin Complex
38 mg
Horsetail
3 mg
hydrolyzed Collagen
50 mg
Alpha Lipoic Acid
10 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free
Report overview
Phosphorus (Dicalcium Phosphate) · 128 mg OverallScore90
B Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyA+ Value

Dicalcium phosphate offers a dependable source with a targeted elemental phosphorus amount. The label makes both source and dose clear, but reaching the serving requires several caplets. Low serving cost still gives the formula strong economic efficiency within a broad nutrient blend.

View ingredientView products
Biotin (D-Biotin) · 5000 mcg OverallScore89
A Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyC Value

The disclosed amount is well aligned with higher-potency biotin use. The named d-biotin form strengthens confidence in biological activity. The available facts support only a neutral value judgment; high-dose biotin can interfere with some laboratory tests, so the dose should be disclosed before blood work.

View ingredientView products
Manganese (Manganese Gluconate) · 2 mg OverallScore82
B+ Active Ingredient Quality & BioavailabilityA- Dose, Safety & Label TransparencyB+ Value

Manganese gluconate provides good solubility and absorption. The clearly stated 2 mg serving supports maintenance but remains below the targeted bone and joint range. A below-median serving cost provides good value for this organic form.

View ingredientView products
Loading alternative details
69 Performance

Extra Strength Hair Skin & Nails

21st Century
<p>Its label clearly provides 1500 mcg of Vitamin A as Retinyl Palmitate, making it a more clearly defined niacin and biotin and choline and calcium and manganese and phosphorus and paba option. Compared with the original, its ingredient and goal alignment is stronger, although the input does not provide independent testing or absorption evidence.</p>
72 Performance

Extra Strength Hair Skin & Nails

Nature's Bounty Optimal Solutions
<p>Its label clearly provides 3 mg of Horsetail, making it a more clearly defined niacin and biotin and manganese and paba option. Compared with the original, its ingredient and goal alignment is stronger, although it does not retain the original product’s choline and calcium and phosphorus coverage.</p>
70 Performance

Hair Skin & Nails

Nature's Truth
<p>Its label clearly provides 1 g of Total Fat, making it a more clearly defined niacin and biotin and paba option. Compared with the original, its ingredient and goal alignment is stronger, although it does not retain the original product’s choline and calcium and manganese and phosphorus coverage.</p>
82 Budget

B-Complex with Rice Bran

NaturesPlus Source of Life Garden
<p>Its label clearly provides 10 mg of Thiamine as Thiamine Hydrochloride, preserving relevant niacin and choline and paba coverage. Compared with the original, it lowers the serving cost, although it does not retain the original product’s biotin and calcium and manganese and phosphorus coverage.</p>
57 Budget

Hair Skin & Nails

21st Century
<p>Its label clearly provides 750mcg RAE of Vitamin A as Vitamin A Palmitate, preserving relevant choline and phosphorus and paba coverage. Compared with the original, it lowers the serving cost, although it does not retain the original product’s niacin and biotin and calcium and manganese coverage.</p>
71 Budget

B Complex

NATURELO Premium Supplements
<p>Its label clearly provides 2 mg of Co-Enzyme Q10 as Ubidecarenone, preserving relevant biotin and choline and paba coverage. Compared with the original, it lowers the serving cost, although it does not retain the original product’s niacin and calcium and manganese and phosphorus coverage.</p>
70 Value

Body Hair Skin & Nails

Mason Natural
<p>Its label clearly provides 900mcg RAE of Vitamin A as Beta-Carotene, keeping the formula relevant to biotin and choline and calcium and manganese and phosphorus and paba. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although it does not retain the original product’s niacin coverage.</p>
70 Value

Hair Skin & Nails

Nature's Bounty Optimal Solutions
<p>Its label clearly provides 2 mg of Riboflavin as Vitamin B2, keeping the formula relevant to niacin and biotin and choline and manganese and phosphorus and paba. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although it does not retain the original product’s calcium coverage.</p>
65 Value

High Potency B-Complex Chewable Natural Orange Flavor

Solaray
<p>Its label clearly provides 250 mg of Vitamin C as Ascorbic Acid, keeping the formula relevant to niacin and biotin and choline and paba. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although it does not retain the original product’s calcium and manganese and phosphorus coverage.</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. 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
  3. 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
  4. Low serum biotinidase activity in children with valproic acid monotherapy.
    Schulpis KH; Karikas GA; Tjamouranis J; Regoutas S; Tsakiris S · Epilepsia · 2001
    Clinical trial125 participantsSkin Health Hair Health forBiotin
  5. 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
  6. Anti-pollution cosmetic-based one-step formation of w/o/w multiple emulsion containing D-biotin for skin protection: fabrication and in vitro and in vivo evaluation.
    Ali A; Iqbal S; Ilyas A; Khan H; Asad MHHB; Fatima N; Akhtar N · Drug delivery and translational research · 2020
    Non-randomized trial15 participantsSkin Health forBiotin
  7. 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
  8. Final report on the safety assessment of biotin.
    Fiume MZ; Cosmetic Ingredient Review Expert Panel · International journal of toxicology · 2002
    Narrative reviewSkin Health forBiotin
  9. 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
  10. 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
  11. Brittle nails: response to daily biotin supplementation.
    Hochman LG; Scher RK; Meyerson MS · Cutis · 1993
    Case series35 participantsNail Health forBiotin
  12. Nail Supplements: When, How, and Why?
    Zaraa I; Richert B · Skin appendage disorders · 2026
    Narrative reviewNail Health forBiotin Nail Health forCollagen
  13. Brittle nails.
    Iorizzo M; Pazzaglia M; M Piraccini B; Tullo S; Tosti A · Journal of cosmetic dermatology · 2009
    Narrative reviewNail Health forBiotin
  14. 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
  15. 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
  16. 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
  17. Topical tretinoin for hair growth promotion.
    Bazzano GS; Terezakis N; Galen W · Journal of the American Academy of Dermatology · 1986
    Non-randomized trial56 participantsHair Health forVitamin A
  18. A review of isotretinoin in the treatment of frontal fibrosing alopecia.
    Shahpar A; Nezhad NZ; Sahaf AS; Ahramiyanpour N · Journal of cosmetic dermatology · 2024
    Systematic review232 participants15 studies pooledHair Health forVitamin A
  19. Efficacy of Isotretinoin and Acitretin in Treatment of Frontal Fibrosing Alopecia: Retrospective Analysis of 54 Cases.
    Rakowska A; Gradzińska A; Olszewska M; Rudnicka L · Journal of drugs in dermatology : JDD · 2018
    Cohort study54 participantsHair Health forVitamin A
  20. Systemic Treatments for Lichen Planopilaris and Frontal Fibrosing Alopecia: A Retrospective Study of 315 Patients.
    Willaert M; Van Dongen T; Dikrama P; Nijsten T; Hijnen D; Waalboer-Spuij R · Acta dermato-venereologica · 2025
    Cohort study315 participantsHair Health forVitamin A
  21. Tretinoin enhances minoxidil response in androgenetic alopecia patients by upregulating follicular sulfotransferase enzymes.
    Sharma A; Goren A; Dhurat R; Agrawal S; Sinclair R; Trüeb RM; Vañó-Galván S; Chen G; Tan Y; Kovacevic M; Situm M; McCoy J · Dermatologic therapy · 2020
    Single-arm trialHair Health forVitamin A
  22. 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
  23. 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
  24. 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
  25. 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
  26. 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
  27. Increased prevalence of vitamin D deficiency in patients with alopecia areata: a systematic review and meta-analysis.
    Lee S; Kim BJ; Lee CH; Lee WS · Journal of the European Academy of Dermatology and Venereology : JEADV · 2018
    Meta-analysis2,039 participants14 studies pooledHair Health forVitamin D
  28. Intralesional vitamin D3 in treatment of alopecia areata: A randomized controlled clinical trial.
    Rashad AF; Elgamal E; Fouda I · Journal of cosmetic dermatology · 2022
    Randomized trial60 participantsHair Health forVitamin D
  29. Vitamin D and its Analogs in Treatment of Mild to Moderate Alopecia Areata: Systematic Review and Meta-Analysis.
    Alsaati AA; Kaliyadan F; Alsaadoun D; Alzakry LM; Alzabadin RA; Hakami TH; Rubaian NFB · Indian dermatology online journal · 2025
    Meta-analysisHair Health forVitamin D
  30. Topical calcipotriol vs narrowband ultraviolet B in treatment of alopecia areata: a randomized-controlled trial.
    El Taieb MA; Hegazy EM; Ibrahim HM; Osman AB; Abualhamd M · Archives of dermatological research · 2020
    Randomized trial60 participantsHair Health forVitamin D
  31. Serum 25 hydroxyvitamin D in non-scarring alopecia: A systematic review and meta-analysis.
    Chen Y; Dong X; Wang Y; Li Y; Xiong L; Li L · Journal of cosmetic dermatology · 2024
    Meta-analysis10,670 participants23 studies pooledHair Health forVitamin D
  32. 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
  33. 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
  34. 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
  35. 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
  36. 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
  37. 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
  38. 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
  39. 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
  40. 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
  41. 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
  42. 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