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

Vitamin A (Retinol & Beta-Carotene) vs. Vitamin E (d-Alpha-Tocopherol)

Comparing 2 standards across 9 specifications. 9 key differences identified.

Comparing:
Vitamin A (Retinol & Beta-Carotene)
Vitamin E (d-Alpha-Tocopherol)

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 E is the principal fat-soluble peroxyl radical-scavenging antioxidant protecting cellular polyunsaturated membrane phospholipids. Adult RDA is 15 mg (22.4 IU) of d-alpha-tocopherol, with a Tolerable Upper Limit of 1,000 mg (1,500 IU)/day.

View full Vitamin E (d-Alpha-Tocopherol) spec sheet →

Specification Comparison Table

9 Parameters
Parameter / Spec
Nutrient Type
Fat-Soluble Isoprenoid Vitamin Fat-Soluble Chromanol Lipophilic Vitamin
Adult RDA / RDI
900 µg RAE / day (Men) / 700 µg RAE / day (Women) 15 mg / day (22.4 IU) of 2R-alpha-tocopherol
Tolerable Upper Limit (UL)
3,000 µg / day (10,000 IU) (Preformed retinol only; no UL for beta-carotene) 1,000 mg / day (1,500 IU synthetic) (Excess impairs Vitamin K clotting cascade)
Chemical Forms
Retinyl Palmitate (Preformed Animal), All-Trans Retinol, Beta-Carotene (Plant Provitamin) RRR-alpha-Tocopherol (Natural d-alpha), all-rac-alpha-Tocopherol (Synthetic dl-alpha), Gamma/Delta-Tocopherols
Primary Biological Function
11-cis-retinal rhodopsin visual cycle, RAR/RXR nuclear receptor gene transcription, Mucosal barrier immunity Breaks lipid peroxidation chain in PUFA cell membranes, protects LDL from oxidative modification, maintains erythrocyte membrane integrity
Deficiency Condition
Nyctalopia (Night blindness), Xerophthalmia, Bitot's spots, Keratinization of mucous membranes Hemolytic anemia, Spinocerebellar ataxia, Peripheral neuropathy, Loss of vibratory/proprioceptive sense
Top Whole Food Sources
Beef Liver, Cod Liver Oil, Sweet Potatoes, Carrots, Spinach, Curly Kale, Butter Wheat Germ Oil, Sunflower Seeds, Raw Almonds, Hazelnuts, Sunflower Oil, Spinach, Hass Avocado
Hepatic Storage
80–90% of total body Vitamin A is stored in hepatic stellate cells as retinyl esters
Hepatic Alpha-TTP Specificity
The liver secretes only alpha-tocopherol into VLDL via Alpha-Tocopherol Transfer Protein (alpha-TTP); other tocopherols are degraded in bile

Other Alternatives to Compare

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