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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 _________________________ metabolism2. 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 ___________________ synthesis3. 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!