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

Vitamin B1 (Thiamine) vs. Vitamin B9 (Folate & Folic Acid)

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

Comparing:
Vitamin B1 (Thiamine)
Vitamin B9 (Folate & Folic Acid)
Vitamin B1 (Thiamine) →

Vitamin B1 is a water-soluble pyrimidine/thiazole vitamin acting as the Thiamine Pyrophosphate (TPP) coenzyme in pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, and transketolase. Adult RDA is 1.2 mg (men) / 1.1 mg (women) (no Upper Limit established).

View full Vitamin B1 (Thiamine) spec sheet →
Vitamin B9 (Folate & Folic Acid) →

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
Vitamin B1 (Thiamine)
Vitamin B9 (Folate & Folic Acid)
Nutrient Type
Water-Soluble Thiazole Vitamin Water-Soluble Pteroylglutamate Vitamin
Adult RDA / RDI
1.2 mg / day (Men) / 1.1 mg / day (Women) (+0.3mg during pregnancy) 400 µg DFE / day (600 µg DFE pregnancy / prevents neural tube defects)
Tolerable Upper Limit (UL)
None Established (Rapid renal clearance of excess) 1,000 µg / day (Synthetic folic acid only; masks B12 deficiency neuropathy)
Chemical Forms
Thiamine Monophosphate, Thiamine Pyrophosphate (TPP / TDP, active coenzyme), Benfotiamine (Lipid-soluble synthetic) (6S)-5-Methyltetrahydrofolate (5-MTHF, active circulating form), Tetrahydrofolate (THF), Folic Acid (Pteroylmonoglutamic acid, synthetic)
Primary Biological Function
Pyruvate dehydrogenase complex (Links glycolysis to Krebs cycle), Transketolase (Pentose Phosphate Pathway), Myelin neurotransmission 1-Carbon transfer reactions, dUMP -> dTMP methylation (Thymidine DNA synthesis), Methionine-Homocysteine cycle, Erythropoiesis
Deficiency Condition
Beriberi (Wet beriberi: high-output heart failure; Dry beriberi: peripheral neuropathy), Wernicke-Korsakoff syndrome Neural Tube Defects (Spina bifida, anencephaly in fetuses), Megaloblastic Macrocytic Anemia, Elevated Homocysteine
Top Whole Food Sources
Pork Tenderloin, Sunflower Seeds, Nutritional Yeast, Enriched Grains, Black Beans, Flaxseeds Beef Liver, Spinach, Asparagus, Brussels Sprouts, Roman Lentils, Chickpeas, Fortified Flours
Thermolability & Alcohol Interaction
Degraded by alkaline pH and high heat cooking; alcohol blocks intestinal active ThTr-1 transport —
MTHFR Genetic Polymorphism
— Homozygous MTHFR C677T variant reduces folate reduction activity by ~70%, benefiting from direct 5-MTHF supplementation

Other Alternatives to Compare

Compare Vitamin B1 (Thiamine) vs. Calcium (Elemental Ca) → Compare Vitamin B1 (Thiamine) vs. Iodine (Elemental I) → Compare Vitamin B1 (Thiamine) vs. Iron (Heme & Non-Heme) → Compare Vitamin B1 (Thiamine) vs. Magnesium (Elemental Mg) → Compare Vitamin B1 (Thiamine) vs. Potassium (Elemental K) → Compare Vitamin B1 (Thiamine) vs. Selenium (Elemental Se) → Compare Vitamin B1 (Thiamine) vs. Sodium (Elemental Na) → Compare Vitamin B1 (Thiamine) vs. Vitamin A (Retinol & Beta-Carotene) → Compare Vitamin B1 (Thiamine) vs. Vitamin B12 (Cobalamin) → Compare Vitamin B1 (Thiamine) vs. Vitamin B2 (Riboflavin) → Compare Vitamin B1 (Thiamine) vs. Vitamin B3 (Niacin / Nicotinic Acid & Nicotinamide) → Compare Vitamin B1 (Thiamine) vs. Vitamin B5 (Pantothenic Acid) → Compare Vitamin B1 (Thiamine) vs. Vitamin B6 (Pyridoxal 5'-Phosphate / PLP) → Compare Vitamin B1 (Thiamine) vs. Vitamin B7 (Biotin / Vitamin H) → Compare Vitamin B1 (Thiamine) vs. Vitamin C (L-Ascorbic Acid) → Compare Vitamin B1 (Thiamine) vs. Vitamin D3 (Cholecalciferol) → Compare Vitamin B1 (Thiamine) vs. Vitamin E (d-Alpha-Tocopherol) → Compare Vitamin B1 (Thiamine) vs. Vitamin K1 (Phylloquinone) → Compare Vitamin B1 (Thiamine) vs. Zinc (Elemental Zn) →