Vitamin B1: Thiamin in Human Nutrition

Thiamin (Vitamin B1)

• RDA: Men 1.2 mg/day, Women 1.1 mg/day
• Functions: Coenzyme TPP (thiamin pyrophosphate) plays a vital role in energy metabolism.
• Sources: Whole grains, fortified/enriched grain products; sensitive to heat.
• Deficiency: Results in Beriberi—wet (edema) and dry (muscle wasting).
• Symptoms: Enlarged heart, cardiac failure, muscular weakness, memory issues, anorexia.

Riboflavin (Vitamin B2)

• RDA: Men 1.3 mg/day, Women 1.1 mg/day
• Functions: Coenzymes FMN and FAD are essential for energy metabolism.
• Sources: Present in dairy, eggs, leafy greens, organ meats; not typically deficient.
• Toxicity: No reported adverse effects.

Pantothenic Acid

• Adequate Intake (AI): Adults 5 mg/day
• Functions: Integral for coenzyme A, crucial for energy metabolism.
• Sources: Widespread across foods, especially organ meats, mushrooms, avocados, grains.
• Deficiency: Rare; may cause gastrointestinal issues, insomnia, fatigue, apathy.
• Toxicity: No adverse effects reported.

Vitamin B6

• Other names: Pyridoxine, Pyridoxal, Pyridoxamine
• RDA: Adults 1.3 mg/day
• Functions: Coenzymes PLP and PMP aid in amino acid/fatty acid metabolism and red blood cell production.
• Sources: Meats, fish, poultry, potatoes, noncitrus fruits, fortified cereals.
• Deficiency: Can lead to scaly dermatitis, small-cell anemia, and neurological symptoms.
• Toxicity: Symptoms include depression, fatigue, nerve damage, and skin lesions.

Folate (Folic Acid)

• RDA: Adults 400 µg/day (DFE)
• Functions: Coenzymes THF and DHF are essential for DNA synthesis and cell formation.
• Sources: Fortified grains, leafy greens, legumes, liver.
• Deficiency: Associated with large-cell anemia and various mental health issues.
• Health implications: Important for preventing neural tube defects and supports heart health.

Vitamin B12

• Other name: Cobalamin
• RDA: Adults 2.4 µg/day
• Functions: Coenzymes used in cell synthesis and maintaining nerve health; crucial for folate metabolism.
• Sources: Animal products (meat, dairy, eggs), fortified cereals; sensitive to microwave cooking.
• Deficiency: Associated with pernicious anemia, characterized by large-cell anemia, fatigue, and nerve degeneration.

Vitamin C (Ascorbic Acid)

• RDA: Men 90 mg/day, Women 75 mg/day
• Functions: Crucial for collagen synthesis, antioxidant protection, iron absorption, immune function support.
• Sources: Citrus fruits, dark green vegetables, tomatoes, strawberries; sensitive to heat and oxygen.
• Deficiency: Leads to scurvy, resulting in anemia, joint pain, poor wound healing, and skin issues.

Niacin (Vitamin B3)

• Other names: Nicotinic acid, Nicotinamide
• Precursor: Dietary tryptophan
• RDA: Men 16 mg NE/day, Women 14 mg NE/day
• Functions: Coenzymes NAD and NADP are vital in energy metabolism.
• Sources: Meats, dairy, eggs, whole grains, enriched cereals; deficiency leads to pellagra (the 4 D's: diarrhea, dermatitis, dementia, death).
• Toxicity: Can cause niacin flush, liver damage, and metabolic issues.

Biotin

• Adequate Intake (AI): Adults 30 µg/day
• Functions: Coenzyme role in energy metabolism, fat synthesis, and amino acid metabolism.
• Sources: Organ meats, eggs, fish, whole grains, and synthesized by GI bacteria.
• Deficiency: May result in hair loss, skin rashes, and neurological impairments.

Learn about the functions, sources, and deficiency disease of Thiamin (Vitamin B1) in human nutrition. Discover its importance in energy metabolism and how it can be easily destroyed by heat.