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

Sodium (Elemental Na) vs. Vitamin A (Retinol & Beta-Carotene)

Comparing 2 standards across 11 specifications. 11 key differences identified.

Comparing:
Sodium (Elemental Na)
Vitamin A (Retinol & Beta-Carotene)

Sodium is the principal extracellular cation (135–145 mEq/L extracellular), maintaining extracellular fluid volume, plasma osmolality, and driving secondary active transport. Adequate Intake (AI) is 1,500 mg/day, with a Chronic Disease Risk Reduction (CDRR) limit of 2,300 mg/day.

View full Sodium (Elemental Na) spec sheet →

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 →

Specification Comparison Table

11 Parameters
Parameter / Spec
Nutrient Type
Essential Macromineral / Major Extracellular Electrolyte Fat-Soluble Isoprenoid Vitamin
Chemical Forms
Sodium Chloride (NaCl, 39.3% Na by weight), Monosodium Glutamate (MSG, 12.3% Na), Sodium Bicarbonate (27.4% Na) Retinyl Palmitate (Preformed Animal), All-Trans Retinol, Beta-Carotene (Plant Provitamin)
Primary Biological Function
Extracellular fluid osmolality maintenance, Blood pressure / volume homeostasis, Action potential depolarization (voltage-gated Na+ channels), SGLT1 glucose cotransport 11-cis-retinal rhodopsin visual cycle, RAR/RXR nuclear receptor gene transcription, Mucosal barrier immunity
Deficiency Condition
Hyponatremia (Serum Na+ < 135 mmol/L): Cerebral edema, Nausea, Muscle cramps, Seizures, Coma (often exercise-associated from over-hydration) Nyctalopia (Night blindness), Xerophthalmia, Bitot's spots, Keratinization of mucous membranes
Top Whole Food Sources
Table Salt (NaCl), Cured Bacon, Soy Sauce, Parmigiano-Reggiano, Pickles, Olives, Bread (Processed food accounts for 70% of intake) Beef Liver, Cod Liver Oil, Sweet Potatoes, Carrots, Spinach, Curly Kale, Butter
Adult Adequate Intake (AI)
1,500 mg / day (Equal to 3.8 g table salt NaCl)
Chronic Disease Limit (CDRR)
2,300 mg / day (Equal to 5.8 g table salt / 1 level teaspoon)
Renal Renin-Angiotensin System
Juxtaglomerular apparatus senses low tubular sodium/pressure, secreting renin to stimulate aldosterone and renal Na+ reabsorption
Adult RDA / RDI
900 µg RAE / day (Men) / 700 µg RAE / day (Women)
Tolerable Upper Limit (UL)
3,000 µg / day (10,000 IU) (Preformed retinol only; no UL for beta-carotene)
Hepatic Storage
80–90% of total body Vitamin A is stored in hepatic stellate cells as retinyl esters