Vitamins: Vital Keys to Health BIOL 103, Chapter 9-2

Today’s Topics The Water-Soluble Vitamins: Eight Bs and a C Bogus Vitamins

Summary of Fat-Soluble Vitamins

The Water-Soluble Vitamins: Eight Bs and a C Primarily coenzymes Antioxidants What to keep in mind about each vitamins: – Function – Food sources – Toxicity vs. Deficiency

What is a Coenzyme? Coenzyme: a small compound that helps enzymes in biochemical reactions. Most coenzymes are derived from vitamins or are made from vitamins.

Thiamin/B1 Functions: – Coenzyme in _______________________________ – Part of the coenzyme: thiamin pyrophosphate (TPP) Helps break down glucose, make RNA and DNA, helps power protein synthesis Helps synthesize and regulate neurotransmitters Food sources: – Pork, legumes, nuts and seeds, fish and seafood, enriched grain product – Cooking ____________________ content

Thiamin/B1 Deficiency: – ________________: overall profound muscle weakness and nerve destruction _____________________________ Occurs with __________________________ because it interferes with B vitamin absorption – Q: Why would Beriberi be more common in Southeast Asia? Toxicity: – None reported

Riboflavin/B2 Functions: 1.Coenzyme in __________________________ (extracts energy from glucose, fatty acids, and amino acids) 2.Supports __________________ Food sources: – Milk and dairy products – Enriched grains, eggs Deficiency: – _________________________________ Usually occurs with chronic alcoholism Toxicity: UL is not set

Niacin/B3 Functions: 1.Coenzyme in _______________________ 2.Supports __________________________ Food sources: – Can be made from ____________________ Need B1, B6, and iron to convert to B3 – Whole and enriched grains – Meat, poultry, fish, nuts, peanuts

Niacin/B3 Deficiency: – ________________: “rough skin” Four D’s: _____________________________________ ______________________________________________ – Can worsen if also deficient in ________________________________________. Toxicity and medicinal uses – High doses used to treat high blood cholesterol – Side effects: ______________________________ __________________________________________

Pyridoxine/B6 Functions: 1.Coenzyme in _________________________ metabolism 2.Supports _______________________ 3.Helps to lower blood levels of homocysteine  reduce risk for heart disease Diagram: Food sources: – Meat, fish, poultry, potatoes, bananas, sunflower seeds

Pyridoxine/B6 Deficiency – _______________________________________ : anemia characterized by small, pale red blood cells that lack adequate hemoglobin to carry oxygen. Can also be caused by deficiency in __________ Toxicity and medicinal uses – Can cause ________________________________ – Other symptoms: upset stomach, headaches, sleepiness, tingling/prickling or burning sensation

Folate/B9 Functions: 1.Coenzyme in _______________________________ 2.Needed for normal ___________________ synthesis 3.Works with ___________________ to help control homocysteine levels Food sources: – Fortified cereals, enriched grains – Green, leafy vegetables Think of folate like foliage

Folate/B9 Deficiency: – _______________________________: Not enough folate  red blood cells cannot form DNA and cannot divide  become large, immature cells  cannot carry oxygen properly  anemia – Birth defects in the Neural Tube: ______________________ – Heart disease from elevated homocysteine levels Toxicity: – Can mask ___________________ deficiency when you take folate supplements

Cobalamin/B12 “Cobalt-containing compounds” (cobalamin) Functions: 1.Needed for normal __________________ functions DNA and red blood cell synthesis Metabolize homocysteine 2.Maintains myelin sheath around nerves  _______ _______________________________ Food sources: – Only animal foods: meats, liver, milk, eggs – Some fortified foods

Cobalamin/B12 Absorption: – Requires ____________________ and ___________________________ Deficiency: – Can be caused by Pernicious anemia: autoimmune disorder that damages stomach linings  reduced B12 absorption – Nerve damage Toxicity: – No UL set

Figure 9.32: Absorption of B12

Pantothenic Acid/B5 Function: 1.Component of __________, which is a part of acetyl CoA  helps extract energy from nutrients and help build fatty acids Food sources: – Widespread in foods – Reduced by _______________ _________________________ Deficiency/Toxicity: Rare

Biotin/B7 Functions: – Acts as a coenzyme in: 1.________________________________ 2.________________________________ 3.________________________________ 4.Release of energy from ____________________ Food sources: – Cauliflower, liver, peanuts, cheese – Protein avidin (raw egg whites) binds biotin and prevents absorption Deficiency and Toxicity are rare

Vitamin C Functions: – _________________________________ – Needed for ________________________ – Other roles: Make other essential compounds (steroid hormones, thyroid hormones, bile salts, parts of DNA) Enhances the absorption of iron from plant foods Food sources: – Fruits: citrus, strawberries, kiwi – Vegetables: broccoli, tomatoes, leafy green, potatoes

Vitamin C Deficiency: – _____________ Toxicity: – May cause ____________________ – For some people: kidney stones, iron toxicity

Choline: A Vitamin-Like Substance Function: – Act as a ___________________ to help metabolize homocysteine Food sources: – Milk, liver, egg yolk, peanuts; overall is abundant in food Deficiency: Unlikely in healthy people Toxicity: – Diarrhea, falling blood pressure, fishy body odor

Bogus Vitamins Bogus vitamins: Unnecessary substances found in some supplements – Examples: hesperidin, para-aminobenzoic acid (PABA), pangamic acid, rutin – Think twice before you buy them!