chapter 10&11: water and fat soluble vitamins - nutrition

vitamins

organic molecule which has a carbon and is an essential micronutrient, needed in small quantities for proper metabolic functioning

• fat soluble

• water soluble

water soluble

vitamins that are absorbed directly into blood and most are not stored in the body

• travel freely into water fluids and readily excreted

• toxicities are unlikely

• non b complex: vitamin C

• b complex: body would lack energy without them since they are part of coenzyme complexes (compounds attracted to sites on enzymes = forms new product)

  • energy releasing (breakdown foods to produce ATP): thamine (B1), riboflavine (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7)

  • hematopoietic (form blood cells and DNA synthesis): folid acid (B9), cyanocobalamn (B12)

fat soluble

vitamins that are first absorbed into lymph then blood

• travel with protein carriers are storage in liver or fatty tissues

• not readily excreted

• toxicities are likely: stored in body fat tissues, instead of excreted by liver, and can accumulate

• vitamins A, D, E, K

thamin (B1)

part of TPP and assists in energy metabolism, breaking down carbs by converting pyruvate to acetyl CoA

• nerve activity: signaling

• muscle activity: contraction

• deficiency: beriberi — in malnourished people, homelessness, and alcohol abuse

  • dry: affects nervous system

  • wet: affects CV system

• food sources: meats/poultry/seafood, grains, fruit

riboflavin (B2)

serves as a coenzyme in energy metabolism, converting nutrients into usable energy

• works thru FMN and FAD — carry electrons in metabolic pathways, such as ETC to make ATP

• deficiency: causes inflammation of membranes (mouth and skn)

• food sources: meats, grains, milk products, eggs

niacin (B3)

two chemical forms that act as a coenzyme in metabolism

• NAD (carries hydrogens and their electrons) and NADP (phosphate form) — energy production

• RDA in equivalents (NE)

• body makes from amino acid typtophan: after protein synthesis needs are met

• deficiency: pellagra — dementia, diarrhea, dermatitis, death

• high dose can be prescribed to lower cholesterol and triglycerides

  • used in patients with cardiac disease/hyperlipidemia

  • lest common due to side effects

• food sources: grains, meats/poultry/seafood, legumes/nuts/seeds

pyridoxine (B6)

come in three forms and involved in metabolism of carbs, amino acids, and fatty acids, by transferring amino groups to help form nonessential amino acids

• ex: convert tryptophan to niacin

• important for neurotransmitter production

• stored in muscle tissue

• deficiency: anemia, depression, weakened immune function

• food sources: fruits, grains, chicken

folate (B9)

converts B12 to its coenzyme form for DNA synthesis, and regenerate methionine from homocysteine

• recycling homocysteine (or else linked to heart disease)

• helps reduce HD risk

• B12 activates folate by removing methyl group — both needed for DNA synthesis

• deficiency: neural tube defects — spinal cord doesn’t close properly, bubble on spine, increase risk of HD and some cancers

• pregnant women must have adequate amounts

• food sources: legumes/nuts, leafy greens, grains

cyanocobalamin (B12)

depends on folate to activate for DNA/RNA synthesis, RBC formation, myelin sheath, amino acid metabolism, bone cell activity, regenerate methionine from homocysteine

• exist as cobalamins with red ion

• requires HCl and intrinsic factor to be absorbed

• stored in the liver enough for ~3 yrs

• comes from microorganisms/animal products

• deficiency:

  • older adults from decreased IF and vegans

  • pernicious anemia: inability of IF to bind, treated with injections

  • malabsorption due to decreased stomach acid and bacteria grows

• supplements can interact with meds

• food sources: organs, meats, fish, dairy, seafood, yeast, cereal, soy

vitamin C

a strong antioxidant, supports immune function, reduce histamine, increase iron absorption, and a cofactor for enzymes

• stress increased needs, higher in smokers with oxidative damage

• can reduce duration and severity of colds, support HD/CV, skin and eye health, aging

• deficiency: scurvy — bleeding gums/hemorrhage on skin, historically seen in pirates/sailors

• RDA: 200 mg max absorption at a time

• sensitive to heat and O2 and loses potency when cooked/exposed to air

• form of ascorbic acid: to extend shelf life (antioxidant effect)

• food sources: fruits, veggies

vitamin A

precursor is beta-carotine, main role in vision, reproductive health, and cell growth

• active form: retinoids — egg yolk, liver

• inactive form: beta carotine — carrots, sweet potato, red pepper (antioxidant)

• one of the most dangerous vitamins in high amts (from animal liver, supplements)

• can lead to liver damage, increased cholesterol, triglycerides

• accutane drug can cause birth defects because it is a derivative

• deficiency: xerophthalmia (dry, cloudy eyes in developing countries) and night blindness

• food sources: sweet potato, carrot, squash, spinach

vitamin D

helps absorb calcium and phosphorus

• come from sunlight (skin has precursors to activate) and food

• supports strong bones and teeth and prevent bone loss

• supports immune system

• reduce risk of osteoporosis

• risk: sedentary, darker tones, limited outdoor activity

• mental: low levels linked to depression and migraines (can use supplements can improve mood)

• food sources: cereal, milk, beef liver, cereal, eggs, pork

vitamin E

strong antioxidant and protects cell membrane integrity

• maintain cell walls, RBC formation, immune system

• often marketed for cancer prevention and disease prevention

  • better received thru whole foods and not supplements

• food sources: egg yolk, nuts/seeds, soybean, whole grain, fruit, spinach and broccoli

vitamin K

controls blood clotting and regulate calcium for bone formation

• activates proteins so calcium can bind to bones and not stay in blood

• produced by gut bacteria in intestines

  • newborns lack and get a shot to prevent bleeding issues

• food sources: green veggies, collard greens