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Water-Soluble Vitamins9 Water-soluble vitamins = 8B’s and 1C!
B1 = Thiamin B2 = RiboflavinB3 = NiacinB5 = Pantothenic AcidB6 = PyridoxineB7 = BiotinB9 = FolateB12 = Cobalamin
Easily destroyed by heat, light, and oxidation
Digestion and
Absorption
Primary FunctionsB vitamins act as coenzymes!Coenzymes are a vital part of some enzymes, so vitamins are needed for enzyme to work properly
These Transform carbohydrates, proteins, and fats to ATP• Thiamin• Riboflavin• Niacin • Pyridoxine• Pantothenic Acid• Biotin
B Vitamins Function as Coenzymes
Primary Functions
– Antioxidant: Vitamin C
– Nerve Function: Thiamin
– Protein Synthesis: Niacin
– Formation of Red Blood Cells: Folate and Cobalamin
– Heart Health Promoted by Several B vitamins
• Energy Metabolism: B Vitamins
B Vitamins Function in
Energy Metabolism
Thiamin (B1)First B vit - *Missing nutrient in unpolished rice.Destroyed in basic solutions; acid solutions protect it.Absorbed - in jejunum (passive diffusion) and activetransport if low intakes
Produces ATP from Carbohydrate Metabolism– TPP activates decarboxylase to form acetyl CoA.– Convert α-ketoglutarate to succinyl CoA TCA cycle.
• Converts branched-chain AA’s to acetyl CoA• Makes pentoses used to synthesize DNA and RNA
Thiamin and Thiamin Pyrophosphate (TPP)
TPP in Energy Metabolism
Thiamin Daily Needs & Food Sources
Food Source
ServingSize
Amount(mg)
DRI/DV(%)
NutrientDensity
Asparagus 1 cup 0.29 24 11.0Sunflower Seeds ¼ cup 0.52 43 3.8Green Peas 1 cup 0.36 30 4.7Flaxseeds 2 Tbs 0.23 19 4.6Brussels Sprouts 1 cup 0.17 14 4.5Navy Beans 1 cup 0.43 36 2.5Black Beans 1 cup 0.42 35 2.8Barley ¼ cup 0.40 33 2.8Dried Peas 1 cup 0.37 31 2.4Lentils 1 cup 0.33 28 2.2Pinto Beans 1 cup 0.33 28 2.0Lima Beans 1 cup 0.30 25 2.1Oats ¼ cup 0.30 25 3.0Sesame Seeds ¼ cup 0.28 23 2.0Kidney Beans 1 cup 0.28 23 1.9Tuna 4 oz 0.15 13 1.5Pineapple 1 cup 0.13 11 2.4
RDA Adults: Males: 1.2mg/day; Females: 1.1mg/day
Thiamin DeficiencyNo known Toxicity but Deficiency is Bad!!!
Beri BeriWasting (wt loss), impaired sensory perception, confusion, derangement, muscle weakness, peripheral neuropathy - nerve degeneration, arythmia.
Classifications:1) Dry: Peripheral nerve damage, wasting without edema.
Psychological disorders.
2) Wet: Edema and congestive heart failure.
3) Infantile: From infancy thiamine deficiency.
Thiamin Insufficiency ↓ACh, Glutamate and GABA All of these act as neurotransmitters, therefore Decrease in these act to depress transmission of nerve impulses!
Wernicke-Korsakoff SyndromeCaused by chronic alcohol abuse depleting thiamin
GABA in Foods!
Riboflavin (B2)Two Coenzyme forms
– Flavin mononucleotide (FMN)– Flavin adenine dinucleotide (FAD)
Heat Stable (cooking) except in UV light
Absorption - Attached to proteins in food
Released in with HCl in stomach
Absorbed by active transport in small intestine
Structures of Riboflavin, FAD and FMN
Involved in E Metabolism Via OxidationFAD and FMN accept hydrogen ions (H+)FADH2 transports e-s to e- Transport Chain (ETC) makes ATP
Food Sources
– Participates in beta-oxidation (Fat Metabolism)– Protects cells from oxidative stress
Metabolic Functions of Riboflavin
Enhances the function of other B vitamins
Riboflavin Daily Needs
RDA Adults: Males: 1.3 mg/day; Females: 1.1 mg/day
The Role of FAD in the TCA Cycle
Ariboflavinosis – inflammation of tissues lining the throat, mouth, tongue, and lips become.
Sore throat, stomatitis, glossitis, cheilosis*
Reduced conversion of B6 to its active form
Altered iron metabolism & syn of Hb (RBCs)
Riboflavin Deficiency
No Toxicity
Deficiency
*Fissuring and dry scaling of lips and angles of the mouth
Niacin (B3)2 Active Forms from food: Nicotinic Acid and Nicotinamide• Converted to Coenzymes
– Nicotinamide adenine dinucleotide (NAD+) – Nicotinamide adenine dinucleotide phosphate
• Bioavailability– Less available in plant foods (wheat grains).– More available in dairy foods and meat.
• Absorbed - small intestine, simple diffusion.
(NADP+)
Niacin is also involved in breaking down alcohol in the body and in the synthesis of fatty acids.
Niacin and Coenzymes NAD+ and NADP+
Metabolic Functions of Niacin• Coenzyme in oxidation-reduction reactions
– Glucose, protein, fat, and alcohol metabolism– Folate and vitamin C Metabolism
• Keeps skin cells healthy and GI tract functioning
• In therapeutic doses:– Lowers total cholesterol in the blood– Lowers triglycerides– Raises HDL cholesterol
NAD+ in Energy Metabolism
Daily Needs for Niacin
RDA Adults: Males: 16 mg/day; Females: 14 mg/dayUL: 35 mg/day
• Synthesized in body from Tryptophan– 60 mg of tryptophan = 1 niacin equivalent (NE)– This requires riboflavin, vitamin B6, and iron
NiacinFood Sources - Meats, fish, poultry & tryptophanHeat and UV light Stable in Foods
• No Toxicity - from food intake!• Excess supplements (and overly fortified foods):
• Reddish coloring of the face, arms, and chest• Nausea, vomiting• Heartburn• Liver toxicity• Raised blood glucose levels
Niacin DeficiencyPellagra (disease of the 4 Ds)
• Dermatitis• Diarrhea• Dementia• Death
Pantothenic Acid (B5)
• Part of Coenzyme A, then makes acetyl CoA• Absorption - small intestine
– If intake is high: Passive diffusion– If intake is low: Active transport
Not stored but high conc found in:• Liver• Kidney • Adrenal glands• Brain
Pantothenic Acid and Energy Metabolism
Metabolic Functions of Pantothenic Acid
Used in fat, carbohydrate, and protein Metabolism.– Fat: makes FA’s and converts them to E– Carbohydrate: Converts pyruvate to acetyl CoA– Protein: Converts AA’s substrates in TCA cycle
Important in Synthesis of:– Cholesterol– Steroid Hormones– Neurotransmitter Acetylcholine (ACh)
Pantothenic Acid Daily Needs and Food SourcesMale and female adults: 5 mg/day• Major Food Sources
Widespread in a large variety - Eggs, fresh vegetables, wheat bran, yeast, meat, milk…
Destroyed by Heat!Processed foods (canned vegetables, fish, meat) are lower than fresh foods in B5.
Pantothenic Acid Deficiency
No Toxicity
• Deficiency: RareSymptoms:
• Fatigue • Nausea• Vomiting• Numbness• Muscle cramps• Difficulty walking
Pyridoxine (B6)
Vitamin B6
Absorption – 75% is Bioavailable (small intestine)By passive diffusion
Bound to albumin and transported to liver
Stored mostly in the muscle, some in the liver
Metabolic Functions of Vitamin B6
• Coenzyme for more than 100 enzymes!• Mostly Protein Metabolism and AA Metabolism• Req in Transamination of non-essential AAs
Involved in:Glycogenolysis and Gluconeogenesis• Makes hemoglobin for RBCs• Assist immune and nervous systems
• Reduce risk for Heart Disease• Reduces Nausea and Vomiting
B6 Daily Needs and Food Sources
RDA Adults Males: 1.3 - 1.7 mg/day; Females: 1.3 - 1.5 mg/dayUL: 100 mg/day
Wide Variety of Food Sources
Meat, fish, poultryFruits and Vegetables Nuts and Legumes
Vitamin B6 Toxicity and DeficiencyToxicity – from excess supplement intake. It attaches to enzymes in muscle and other tissue & remains in body.
B6 Deficiency Symptoms– Sore Tongue– Inflammation of the skin– Depression– Confusion
Microcytic Hypochromic AnemiaRed blood cells are small and pale.
Excessive alcohol consumption depletes B6
Biotin (B7)• Contains Sulfur (S)!• Absorption - Biotinidase removes biotin from food.
– Active transport in Small Intestine– Absorbed in the liver
Metabolic Functions of Biotin
• Coenzyme for E Metabolism– Synthesis of Fatty Acids– Amino Acid Metabolism– Replenishes oxaloacetate from pyruvate
• DNA replication and transcription of genes
• Cell develp & growth - Healthy Hair and Nails
Biotin (B7)
Biotin Daily Needs and Food Sources
• Adults: Males and females: 30 μg/day;
Major Food Sources– Yeast– Liver and other organ meats– Bacteria in the GI tract– Egg yolks– Whole grains– Fish– Many Nuts
Biotin Toxicity and Deficiency• Toxicity: Very Rare
Deficiency:• Can be from eating too many raw egg whites. The
Avidin in it binds biotin => deficiency symptoms• Total parenteral nutrition• Impaired absorption• Rare genetic disorders
Symptoms:Hair loss, depression, conjunctivitis, dermatitis, lethargy, hallucinations
Folate B9
• Folate - the Natural Form of B9 in foods• Folic Acid - synthetic form (added to foods and in supplements)
• Extremely important to have optimal Folate during pregnancy.
• Most folate in foods = Polyglutamate form.• Absorption – only one glutamate kept during
digestion in small intestine• Active form: Tetrahydrofolate - transported to liver.
FolateFolic acid is more bioavailable than folate.Folate destroyed with Heat and Light exposure.Raw Foods have more folate than cooked foods.
Some foods have enzymes that inhibit folate availability.
e.g. Beans, legumes, and cabbage!
Metabolic Functions of Folate
• Transfers C’s to form new compounds• DNA and AA Synthesis• Homocysteine metabolism• Assists in Neural Tube development prevents:
– Neural tube defects– Anencephaly– Spina bifida
• May prevent cancer and Heart Disease
Daily Needs for Folate
Synthetic folic acid absorbed 1.7 times more than Folate.• RDA Adults: Males and females: 400 μg/day• Pregnant women and childbearing age: 400 μg/day – UL: 1,000 μg/day
No Toxicity from foods sources of FolateExcess intake fortified food or supplements (mask a B12 deficiency)
Food Sources of Folate
Dark green leafy vegetables, legumes, seeds and Liver
FoodSource
ServingSize
Amount(mcg)
DRI/DV(%)
NutrientDensity
Lentils 1 cup 358.38 90 7.0Asparagus 1 cup 268.20 67 30.5Spinach 1 cup 262.80 66 28.6Turnip Greens 1 cup 169.92 42 26.5Broccoli 1 cup 168.48 42 13.9Beets 1 cup 136.00 34 8.2Romaine Lettuce 2 cups 127.84 32 36.0Bok Choy 1 cup 69.70 17 15.4Cauliflower 1 cup 54.56 14 8.6Parsley ½ cup 46.21 12 19.0Pinto Beans 1 cup 294.12 74 5.4Garbanzo Beans 1 cup 282.08 71 4.7Black Beans 1 cup 256.28 64 5.1Navy Beans 1 cup 254.80 64 4.5Kidney Beans 1 cup 230.10 58 4.6Papaya 1 med 102.12 26 3.9Brussels Sprouts 1 cup 93.60 23 7.5Green Peas 1 cup 86.78 22 3.4Bell Peppers 1 cup 42.32 11 6.7Green Beans 1 cup 41.25 10 4.2
Folate DeficiencyInterferes with normal red blood cell divisionMegaloblasts → macrocytes → macrocytic anemia
RBCs abnormally large!
– Macrocytic Anemia– Fatigue– Weakness– Irritability – Shortness of breath
Folate Deficiency Linked to Parkinson's Disease
Cobalamin (B12)2 Forms - Both contain Cobalt.
The protein called intrinsic factor (IF), made in stomach helps the intestines absorb vitamin B12.
Vitamin B12 bound to proteins in food and R protein in saliva goes with it to collect it.
The Absorption of Vitamin B12
Vitamin B12• Stored mostly in the liver • Excreted through the bile and urine• Deficiency can take years to develop.
Metabolic Functions of Vitamin B12
• 2 Coenzymes Methylcobalamin: homocysteine to methionine;(prevents homocysteine* buildup)Deoxyadenosylcobalamin: Succinyl CoA in TCA cycle
• Activates Folate!• Synthesis of new cells, esply RBCs• Maintains myelin sheath of nerves• Catabolism of AAs and FAs for E Metabolism
Daily Needs for Vitamin B12
RDA Adult: Males and Females: 2.4 μgAtrophic gastritis: Reduction in HCl production andB12 not released from protein in food
Bad Bacterial overgrowth reduces B12 absorption
Absorption of the synthetic form is not hindered
Insufficient intrinsic factor & gastric bypass ↓ absorption
Microwave cooking reduces active form by 30-40%.
Vitamin B12 Deficiency
No Toxicity
Macrocytic AnemiaPernicious AnemiaFatigueShortness of breathPeripheral Neuropathy (tingling & numbness arms/legs)
• Zero intake (vegan diets)• Malabsorption (HCl)• ↓Pancreatic Enzymes• Gastric Bypass
Deficiency:
Pernicious, Latin meaning ‘destructive’
Pernicious Anemia is a decrease in healthy red blood cells from lack of vitamin B12.
Need to eat meat, poultry, shellfish, eggs, and dairy products to get this vitamin.
FoodSource
ServingSize
Amount(mcg)
DRI/DV(%)
NutrientDensity
Sardines 3 oz 8.11 338 32.2Salmon 4 oz 5.67 236 27.0Tuna 4 oz 2.66 111 13.5Cod 4 oz 2.62 109 20.4Lamb 4 oz 2.51 105 6.1Scallops 4 oz 2.44 102 14.5Shrimp 4 oz 1.88 78 10.4Beef 4 oz 1.44 60 6.2Yogurt 1 cup 0.91 38 4.6Cow's milk 4 oz 0.55 23 5.5Eggs 1 0.55 23 5.3Turkey 4 oz 0.42 18 1.9Chicken 4 oz 0.39 16 1.6Cheese 1 oz 0.24 10 1.6
Food Sources of Vitamin B12
Vitamin CAscorbic AcidWe Humanoids lack enzyme to make vit C : (Absorption - Small intestine by active transportHigher intakes => simple diffusion stomach & intestine
Absorption decreases 50% with intakes > 1 gMore is more likely to be absorbed!Excreted via kidneys, not stored in the body
Metabolic Functions of Vitamin C
• Collagen Synthesis – Crucial for tissue Health!
• Antioxidant– Reduces risk for heart disease and cancer– Accepts/donates e-s to balance free radicals
• Iron absorption is enhanced.
More Functions of Vitamin C• Boosts the immune system
– Promotes WBC synthesis
• May reduce the body's response to stress
• Aids in the conversion of tryptophan and tyrosine to serotonin and norepinephrine
• Aids in the synthesis of thyroxine
• Converts cholesterol to bile
• Assists with histamine breakdown
Daily Needs for Vitamin CRDA Adults: Males: 90 mg/day; Females: 75 mg/day
Smokers: + 35 mg/day!UL: 2,000 mg/day
Consuming > 3,000mg can cause nausea, stomach cramps, and diarrhea.
Vitamin C Toxicity and Deficiency• Deficiency
ScurvyPrevented with 10mg of vitamin C per day
Scurvy first presents with:Fatigue and then formation of spots on the skin, spongy gums, and bleeding from mucous membranes.
Person feels depressed, pale and partially immobilized.
Advanced scurvy shows open suppurating (pus filled) wounds, loss of teeth, yellow skin, fever, neuropathy and finally death from bleeding.
Other Vitamin-Like Compounds• Some compounds are not vitamins but
essential to overall health. • Usually enough made in body • May become essential, e.g., during illness or
chronic diseaseCholine Carnitine Lipoic acidInositol
Choline - cannot be synthesized by body…
Grouped with the B vitamins (but not a vit)Major Functions
– Part of phospholipid that makes up the cell wall– Liver metabolism– Precursor to acetylcholine (nerve transmission)– Assists in Lipid Transport – For Fetal Development
Major Food SourcesAnimal sources: milk, liver, eggs
Carnitine, Lipoic Acid, and InositolAll synthesized by body
Carnitine– Needed to properly utilize fat– Food sources = Meat and dairy products
Lipoic Acid– Helps cells generate energy– Potential antioxidant effects
Inositol– Assists Cell Membranes– Food sources – some plants