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

Vitamin A (Retinol & Beta-Carotene) vs. Vitamin B9 (Folate & Folic Acid)

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

Comparing:
Vitamin A (Retinol & Beta-Carotene)
Vitamin B9 (Folate & Folic Acid)

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 B9 comprises natural dietary folates (polyglutamates) and synthetic folic acid (monoglutamate). Adult RDA is 400 µg DFE, with a Tolerable Upper Limit of 1,000 µg/day synthetic folic acid, essential as a single-carbon donor in thymidylate DNA synthesis and neural tube closure.

View full Vitamin B9 (Folate & Folic Acid) spec sheet →

Specification Comparison Table

9 Parameters
Parameter / Spec
Nutrient Type
Fat-Soluble Isoprenoid Vitamin Water-Soluble Pteroylglutamate Vitamin
Adult RDA / RDI
900 µg RAE / day (Men) / 700 µg RAE / day (Women) 400 µg DFE / day (600 µg DFE pregnancy / prevents neural tube defects)
Tolerable Upper Limit (UL)
3,000 µg / day (10,000 IU) (Preformed retinol only; no UL for beta-carotene) 1,000 µg / day (Synthetic folic acid only; masks B12 deficiency neuropathy)
Chemical Forms
Retinyl Palmitate (Preformed Animal), All-Trans Retinol, Beta-Carotene (Plant Provitamin) (6S)-5-Methyltetrahydrofolate (5-MTHF, active circulating form), Tetrahydrofolate (THF), Folic Acid (Pteroylmonoglutamic acid, synthetic)
Primary Biological Function
11-cis-retinal rhodopsin visual cycle, RAR/RXR nuclear receptor gene transcription, Mucosal barrier immunity 1-Carbon transfer reactions, dUMP -> dTMP methylation (Thymidine DNA synthesis), Methionine-Homocysteine cycle, Erythropoiesis
Deficiency Condition
Nyctalopia (Night blindness), Xerophthalmia, Bitot's spots, Keratinization of mucous membranes Neural Tube Defects (Spina bifida, anencephaly in fetuses), Megaloblastic Macrocytic Anemia, Elevated Homocysteine
Top Whole Food Sources
Beef Liver, Cod Liver Oil, Sweet Potatoes, Carrots, Spinach, Curly Kale, Butter Beef Liver, Spinach, Asparagus, Brussels Sprouts, Roman Lentils, Chickpeas, Fortified Flours
Hepatic Storage
80–90% of total body Vitamin A is stored in hepatic stellate cells as retinyl esters
MTHFR Genetic Polymorphism
Homozygous MTHFR C677T variant reduces folate reduction activity by ~70%, benefiting from direct 5-MTHF supplementation

Other Alternatives to Compare

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