Vitamins A - K

Vitamins A-K are essential nutrients our bodies need for various functions. Here's a closer look at each:

Vitamin A:

• Forms: Retinol (usable form), retinal, retinoic acid (metabolized form)
• Provitamin A: Beta-carotene (converted to vitamin A in the body)
• Sources: Liver, eggs, dairy, fortified foods (preformed vitamin A) & vegetables (provitamin A)
• Functions: Vision (retina, rhodopsin), immune system, skin health, growth and development

Vitamin B Complex (water-soluble):

• B vitamins (individual names & functions listed below)
• Sources: Whole grains, legumes, nuts, leafy greens, fortified foods
• Functions: Energy metabolism, enzyme activity (coenzymes), red blood cell production, nervous system and brain function, DNA synthesis

Vitamin C:

• Ascorbic acid
• Source: Citrus fruits, berries, kiwi, peppers, broccoli
• Functions: Antioxidant (scavenging free radicals), collagen synthesis (connective tissue), wound healing, iron absorption, immune function

Vitamin D:

• Forms: Cholecalciferol (D3, from sunlight), Ergocalciferol (D2, from plants)
• Sources: Sunlight exposure, fatty fish, cod liver oil, fortified foods
• Functions: Bone health (calcium absorption), immune modulation, cell growth

Vitamin E:

• Forms: Tocopherols, tocotrienols
• Sources: Nuts, seeds, vegetable oils, wheat germ
• Functions: Antioxidant (free radical scavenger), cell membrane protection, immune function

Vitamin K:

• Forms: Phylloquinone (K1, from plants), Menaquinones (K2, from bacteria and animal sources)
• Sources: Leafy greens, Brussels sprouts, broccoli, kale (K1), fermented foods, meats, cheeses (K2)
• Functions: Blood clotting, bone metabolism (vitamin K-dependent proteins)