# item.guide
Side-by-Side Comparison Essential Vitamins & Minerals

Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B7 (Biotin / Vitamin H)

Comparing 2 standards across 10 specifications. 10 key differences identified.

Comparing:
Vitamin A (Retinol & Beta-Carotene)
Vitamin B7 (Biotin / Vitamin H)
Vitamin A (Retinol & Beta-Carotene) →

Vitamin A is an essential fat-soluble isoprenoid comprising preformed retinol and provitamin A carotenoids. Adult RDA is 900 µg RAE (men) / 700 µg RAE (women), with a Tolerable Upper Limit of 3,000 µg/day preformed retinol, essential for rhodopsin retinal photoreception, epithelial differentiation, and immune cell proliferation.

View full Vitamin A (Retinol & Beta-Carotene) spec sheet →
Vitamin B7 (Biotin / Vitamin H) →

Vitamin B7 is an essential sulfur-containing water-soluble vitamin serving as a prosthetic group for five carboxylase enzymes in gluconeogenesis, lipogenesis, and branched-chain amino acid catabolism. Adequate Intake (AI) is 30 µg/day (no Upper Limit established).

View full Vitamin B7 (Biotin / Vitamin H) spec sheet →

Specification Comparison Table

10 Parameters
Parameter / Spec
Vitamin A (Retinol & Beta-Carotene)
Vitamin B7 (Biotin / Vitamin H)
Nutrient Type
Fat-Soluble Isoprenoid Vitamin Water-Soluble Ureido-Tetrahydrothiophene Vitamin
Tolerable Upper Limit (UL)
3,000 µg / day (10,000 IU) (Preformed retinol only; no UL for beta-carotene) None Established (No adverse effects recorded)
Chemical Forms
Retinyl Palmitate (Preformed Animal), All-Trans Retinol, Beta-Carotene (Plant Provitamin) D-Biotin (Biologically active isomer), Biocytin (Biotinyl-lysine)
Primary Biological Function
11-cis-retinal rhodopsin visual cycle, RAR/RXR nuclear receptor gene transcription, Mucosal barrier immunity Prosthetic group for Pyruvate Carboxylase (Gluconeogenesis), Acetyl-CoA Carboxylase (Fatty acid synthesis), Propionyl-CoA Carboxylase, Histone biotinylation
Deficiency Condition
Nyctalopia (Night blindness), Xerophthalmia, Bitot's spots, Keratinization of mucous membranes Alopecia (Hair loss), Erythematous scaly periorofacial rash, Brittle nails, Neurological depression / hallucinations
Top Whole Food Sources
Beef Liver, Cod Liver Oil, Sweet Potatoes, Carrots, Spinach, Curly Kale, Butter Egg Yolk, Beef Liver, Salmon, Pork Chop, Sunflower Seeds, Almonds, Sweet Potatoes
Adult RDA / RDI
900 µg RAE / day (Men) / 700 µg RAE / day (Women) —
Hepatic Storage
80–90% of total body Vitamin A is stored in hepatic stellate cells as retinyl esters —
Adult Adequate Intake (AI)
— 30 µg / day (35 µg during lactation)
Raw Egg White (Avidin) Interaction
— Raw egg albumen contains avidin glycoprotein which binds biotin with Kd ~10^-15 M (the strongest non-covalent bond known), completely blocking absorption unless cooked

Other Alternatives to Compare

Compare Vitamin A (Retinol & Beta-Carotene) vs. Calcium (Elemental Ca) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Iodine (Elemental I) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Iron (Heme & Non-Heme) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Magnesium (Elemental Mg) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Potassium (Elemental K) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Selenium (Elemental Se) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Sodium (Elemental Na) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B1 (Thiamine) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B12 (Cobalamin) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B2 (Riboflavin) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B3 (Niacin / Nicotinic Acid & Nicotinamide) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B5 (Pantothenic Acid) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B6 (Pyridoxal 5'-Phosphate / PLP) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B9 (Folate & Folic Acid) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin C (L-Ascorbic Acid) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin D3 (Cholecalciferol) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin E (d-Alpha-Tocopherol) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Vitamin K1 (Phylloquinone) → Compare Vitamin A (Retinol & Beta-Carotene) vs. Zinc (Elemental Zn) →