Water-Soluble Vitamins

What are the over-arching properties of water-soluble vitamins?

• can leach out of foods

• not stored in body → excreted in urine

• destroyed by heat, light, pH, and oxidation

• key functions: energy production coenzymes

What B vitamins are present in energy metabolism?

• NAD

  • niacin-based

• CoA

  • pantothenic acid-based

• PLP

  • B6-based

• TPP

  • thiamin-based

• FAD

  • riboflavin-based

What is the key role of thiamin (B1)?

• involved in energy production

• converted to coenzyme TPP

• protein metabolism

• needed for DNA and RNA synthesis

What food sources are thiamin present in?

• present in enriched-grain products

  • cereals, bread, pasta, rice

• naturally occurring in

  • whole grains

  • nuts

  • legumes

  • pork

What is the disease of thiamin (B1) deficiency?

• beriberi

  • loss of appetite, weight loss

What is a neurological disorder from advanced thiamin deficiency?

• Wernicke-Korsakoff Syndrome

  • associated with chronic high ETOH consumption

What is the key function of riboflavin (B2)?

• energy metabolism coenzyme

  • hydrogen ion donator/acceptor

  • FAD → FADH

• occurs in

  • TCA cycle (reduction to FADH2)

• boosts function of other B-complex vitamins

What can happen from deficiency of riboflavin (B2)?

• aribofalvinosis

  • inflammation of the mouth and throat

What are riboflavin dietary sources?

• milk and yogurt

• enriched cereals and grains

• spinach

• almonds eggs

What can riboflavin be destroyed by?

• can be destroyed by UV light

What is the function of niacin (B3)?

• NAD+ → catabolic reactions

  • produce energy, carry electrons to ETC

What are the food sources of niacin?

• meat, fish, poultry

What can happen from deficiency of niacin?

• pellagra

  • 4 D’s: dermatitis, dementia, diarrhea, and death

What is the function of pantothenic acid (B5)?

• component of coenzyme A

  • coenzyme A + 2-carbon acetyl group → acetyl coa

What are the highest sources of pantothenic acid?

• “pan” → everywhere

• highest sources

  • whole grains

  • nuts

  • meat

  • milk

  • eggs

What can pantothenic acid be destroyed by?

• can be destroyed by heat

What is the function of biotin?

• coenzyme function

  • adds CO2 to compounds in energy metabolism reactions

    • replenishes oxaloacetate

• DNA replication

What are the food sources of biotin?

• peanuts

• egg yolks

• whole grains

• fish

What is vitamin B6? What is its function?

• pyridoxine

• involved in red blood cell synthesis

• reduces N/V in pregnancy

What are the dietary sources of vitamin B6?

• available from many

What is the most important function of folate?

• prevention of neural tube defects in developing fetus

What are the dietary sources of folate?

• law requires folic acid enrichment in refined grains

• natural food sources

  • leafy greens

  • asparagus

  • leguemes

  • seeds

How much do adults need of folate equivalents?

• 400 mg

What happens during folate deficiency?

• risk of neural tube defects

• macrocytic anemia

  • formation of large, immature RBCs: megaloblasts

  • develop into large RBCs: macrocytes

  • reduced oxygen-carrying capacity

What is the family of compounds of vitamin B12 called?

• cobalamin

How are vitamin B12 digested and absorbed? Where is it stored?

• chief cells produce pepsin that hydrolyzes B12 bonds

• parietal cells in the stomach produce

  • intrinsic factor (IF) that binds to B12

• IF releases B12 and binds to transcobalamin for transport

• B12 is stored in the liver

What are the functions of vitamin B12?

• 2 coenzymes

• activates folate

What food sources are vitamin B12 from?

• naturally occurring only in animal-based food sources

What happens if deficient in vitamin B12?

• pernicious anemia

What are the functions of vitamin C?

• tissue synthesis

  • collagen

What are the food sources of vitamin C?

• fruits and veggies

What is the deficiency of vitamin C called?

• scurvy

  • bleeding gums and rashes