KINE 2P20 Week 9 (Chapter 8) Water-soluble Vitamins PDF

KINE 2P20 (D2) 2024-25 FW Intro to Nutrition Water-soluble Vitamins (Chapter 8) Vitamins Objectives Describe the role of vitamins in normal physiological function/metabolism? Understand the most prominent dietary sources of each vitamin? Outline the DRI for each vitamin in a...

KINE 2P20 (D2) 2024-25 FW Intro to Nutrition Water-soluble Vitamins (Chapter 8) Vitamins Objectives Describe the role of vitamins in normal physiological function/metabolism? Understand the most prominent dietary sources of each vitamin? Outline the DRI for each vitamin in adults? Discuss what symptoms and pathologies are associated with vitamin deficiencies? Vitamins Vitamins are _________________________ that promote growth/health Water-soluble and fat-soluble categorization (what is solubility?) B-vitamins originally thought to be one chemical substance – Group of chemically distinct compounds, acting as co-factors/coenzymes B ‘Complex’ (i.e., B1, B2, B12) Water-Soluble Vitamins Fat-Soluble Vitamins What happened to B4, B8, B10, B11? B vitamins Vitamin A Thiamin (B1) Vitamin D Riboflavin (B2) Vitamin E Niacin (B3) Vitamin K Biotin (B7) Pantothenic acid (B5) Vitamin (B6) Folate (B9) Vitamin (B12) Vitamin C Vitamins in foods across groups/categories Improving the nutrient profile of foods Regulated by Health Canada Examples (starting in the 1930’s): _________ with thiamine, riboflavin, niacin, iron, and folic acid _______________, dairy and other products with Vitamin D Vitamins in the digestive tract  Vitamin digestion and absorption Digestive enzymes help to release vitamins from foods Other factors? (_____________________________________) 40-90% of vitamins in foods are absorbed in the _____________________ Fat-soluble vitamins require ________________________ to be absorbed (packaged as chylomicrons – SI transport) Some vitamins are absorbed in inactive _________________ or vitamin precursor forms (activated in the body) “______________”: The related forms of a vitamin that exist in the body that perform the same function Vitamins function as ‘coenzymes’ and ‘cofactors’ B Vitamins: Co-enzymes for energy metabolism Water-soluble Vitamins Thiamin (B1) Men (19-50yrs): 1.2 mg/day Women (19-50yrs): 1.1 mg/day No TUL Thiamin (B1) Coenzyme in ________________, needed for ______________ production (ACh), pentose synthesis (i.e., ribose for RNA) Thiamin is widely available in foods and as a ______________ enriched grains, whole grains, legumes, nuts and seeds Thiamin (B1) deficiency ‘__________’ – lethargy, fatigue, neurological symptoms – More common in poorer countries (fewer fortified grains, e.g. white rice) ____________- problems Congestive heart failure Weakness, irritability _____________ across body _____________ pain Riboflavin (B2) Men (19-50yrs): 1.3 mg/day Women (19-50yrs): 1.1 mg/day No TUL Riboflavin (B2) Coenzyme in energy metabolism ____________________: FMN – flavin mononucleotide FAD – flavin adenine dinucleotide Riboflavin is easily destroyed by heat and exposure to light Riboflavin deficiency ______________________ – inflammation of eyes, lips/mouth, tongue, skin eruptions, cracked lips. Rarely seen alone, occurs with other B-vitamin deficiencies Niacin (B3) Men (19+ yrs): 16 mg/day Women (19+ yrs): 14 mg/day TUL: 35 mg/d Niacin toxicity (overuse of supplements), cardiac arrhythmias, hypertension, nausea, vomiting Niacin (B3) Nicotinamide, nicotinic acid (form metabolic coenzymes) Can be made from __________________________ Grains are often fortified Niacin plays an important role in energy metabolism – Electron carriers for ATP production: NAD/NADH+, NADP Niacin is involved in serotonin production and CNS function Deficiencies can impact _______________________________ Measurement: Niacin equivalents (NE) NE: the amount of niacin present in food Can be synthesized indirectly from tryptophan Both are included in quantification of food nutrient content 1 NE = 1 mg nicotinic acid or niacinamide 60 mg tryptophan = 1 mg niacin = 1 mg of NE E.g., Food contains 30 mg tryptophan and 0.5 mg niacin = 1 NE Niacin deficiency _______________: fatigue, reduced appetite, indigestion 3 D’s: dermatitis, diarrhea, and dementia Cracked, inflamed skin on areas exposed to sunlight Seen mostly in countries with corn or maize based diets due to _________________________ Treatment of these grains with alkalies (e.g., lime) enhances niacin bioavailability Vitamin (B6) Men and Women (19+ yrs): 1.3 mg/day Toxicity: Supplemental levels Figure 8.18 Vitamin B6 Also called pyridoxal, pyridoxine, and pyridoxamine Converted into pyridoxal phosphate, required for >100 enzyme reactions in the body Coenzyme in amino acid synthesis and ______________ Helps convert tryptophan to niacin Roles in immune response, steroid hormone actions, neurotransmitter and myelin synthesis, glycogen metabolism, hemoglobin synthesis Functions of Vitamin B6 Figure 8.19 Functions of Vitamin B6 Figure 8.21 Vitamin (B6) Mandatory ________________ in meal replacements, simulated egg products, can be added to cereals. Vitamin B6 deficiency: ____________ (impaired hemoglobin synthesis), depression, headaches, confusion, numbness, tingling in extremities (neurological), seizures Biotin (B7) Biotin in the diet Liver, egg yolks, yogurt, nuts Biotin in the body Coenzyme involved in adding COOH group to other molecules (e.g., citric acid cycle, glucose synthesis). Biotin deficiency Uncommon, hair loss, dermatitis, nausea, neuromuscular dysfunction Recommended biotin intake AI for adults = 30 µg/day Folate / folic acid (B9) Men / Women (19+ yrs): 400 mcg/d TUL: 1000 mcg (suppl.) Pregnancy (and child-bearing years): 600 mcg/d Figure 8.24 Folate / folic acid (B9) Folate in foods is ___________________ vs. folic acid in supplements (and fortification) DFE: ___________________________ 1 DFE = 1 mcg folate = 0.6 mcg folic acid in food, OR = 0.5 mcg folic acid supplement Figure 8.23 Fortification: white flour, corn meal, pasta, infant formula, prenatal vitamins, instant breakfast, meal replacements Folate deficiency and neural tube defects Folate: Essential for DNA replication, synthesis and expression, and metabolism of some amino acids Low folate intake à ________________(needed for homocysteine Figure 8.27 breakdown), and Megaloblastic/Macrocytic ____________ Supports essential growth and development of tissues (i.e., in pregnancy) Low folate intake in early pregnancy à _______________________ Figure 8.27 Folate deficiency Vitamin (B12) Men / Women (19+ yrs): 2.4 mcg/d No TUL Figure 8.29 Vitamin (B12) Found almost exclusively in _______________________ – ______________ are at particular risk for deficiency – Small amounts in mushrooms, nutritional yeast, tempeh, algae/seaweed (‘nori’) Some mandatory fortifications (infant formula, meal replacements, egg products) Necessary for myelin production Single carbon metabolism (methylation) Vitamin (B12) deficiency Primary deficiency is rare - ___________________ B12 Deficiency can lead to: – Pernicious Anemia (inability to absorb B12 in the gut) – Megaloblastic/Macrocytic anemia (like folate) – Unrelated to iron availability (as in anemia) Vitamin B12 discovered in 1948 – Provided __________ via injection, gel, mega-dosage Excessive intake of folic acid can mask B12 deficiencies No anemia but other neurological symptoms Vitamin C Men (19+ yrs): 90 mg/d Women (19+ yrs): 75 mg/d UL: 2000 mg/d Figure 8.29 Vitamin C Ascorbate or ascorbic acid Many important roles in the body, including ________ support, production of _______, as a cofactor for ______ (esp. iron), scavenging ‘___________’ Is sensitive to heat/light/oxygen and can be degraded in food prep/cooking Vitamin C Ascorbate or ascorbic acid Choline Men: AI (550 mg/d) Women: AI (425 mg/d) Not a true ‘______’ (some endogenous product but dietary supply needed) Adequate Intake range (i.e., _____ not determined for different groups) Critical for many important physiological processes: _____________ (synthesis and integrity of membrane, signalling) _______________(synthesis of neurotransmitter acetylcholine) Fat transport and metabolism, cholesterol regulation Complete Choline deficiency (quite rare, unlikely in humans) Liver/muscle abnormalities, fetal development