Vitamins_sum'15_student notes - Vitamins Part 1 Intro Fat...

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Unformatted text preview: Vitamins Part 1: Intro & Fat Soluble Vitamins BE T H KI T CHI N P H D RDN ASSI STANT PRO F ESSO R UAB DEPART M E NT O F NUT RI T I O N S CI E NCE S Historical Perspective •Funk coined the term “vitamin” in 1912 •Vitamin A was identified in 1913 •Vitamin B12 was identified in 1947 What vitamins look like: Vitamins are individual units Vitamins do not break down into energy Some vitamins have precursors - the corners are carbons and they are organic which means they can be destroyed by light and heat - vitamins are not stable like minerals - some vitamins have inactive forms like vitamin D - vitamin bioavailability - how well the vitamin is absorbed - how well it is able to be used by tissues and cells of body Bioavailability depends on many factors What are those factors? 1 Factors that Affect Bioavailabilty Water soluble vs. fat soluble Efficiency of digestion Previous nutrient intake/status Other foods eaten at the same time Method of food preparation Source of nutrient (natural vs. synthetic) Fractional absorption - fat soluble vitamins often need protein carriers and bc they are stored in the fat, some of these things may make them less bioavailable - water soluble vitamins need to be solubilized in water so that they can be absorbed and used which makes them a bit more bioavailable - not all vitamins need to undergo digestion because a lot of them are single units and a lot of them are absorbed the way they are - fractional absorption - the body only absorbs a certain percentage of the nutrient - more is not always better bc you can start to have some adverse consequences at really high levels of vitamin C Everything has an upper limit! Fat soluble vitamins (A,D,E,K) - fat soluble vitamins are hydrophilic - they need fat and are found in fatty parts in food - stored in fat tissues - we do not neccessarily have to get these every day - not easily excreted but water soluble vitamins are - may require protein carriers to be absorbed - easier to get toxic levels of fat soluble vitamins 2 Vitamin A and Beta-Carotene Remain as betacarotene – role as an antioxidant Retinyl Esters in animal foods Retinol – supports reproduction Beta-Carotene in plant foods Retinal role in vision - vitamin A: there are three forms that we need in the body - retinal, retinol, and retinoic acid - you can essentially get all forms of Vitamin A through the Retinyl Esters - beta carotene is a precursor to vitamin A: it can either stay as beta-carotene in the body but it can also be converted to retinal - even if you are vegeterian you can still get all forms of Vitamin A because you can make all forms from beta-carotene Retinoic Acid – regulates growth Beta Carotene Retinol Vitamin A and Vision - vitamin A plays a role in vision in cornea and retina - it is a part of rhodopsin which is a protein that absorbs the light and helps you see and sends info to brain - when you recover, when a light goes out and there is a bright flash of light, you recover bc of Vitamin A - with Vitamin A deficiancy you may not have the ability to quickly recover from that bright flash of light - because vitamin a helps cells to form mucus, if you are vitamin A deficient, the cornea wont be kept moist by the mucus, keratin gets hardened and makes it hard for you to see 3 - vitamin A - vitamin A plays role in bone health - too much vitamin A weakens the bones - we all have bone turnover and what happens in our bone is that osteoplasts get rid of old bone so that we can make new bone - vitamin A plays a role in the osteoclast removing old bone - with excessive vitamin A you lose more bone than you can rebui 4 Vitamin D - vitamin D plays major role into helping you absorb calcium - vitamin D is more like a hormone - vitamin D produced in one tissue then gets sent out to other tissues where it plays its role which is the definition of a hormone pretty much - vitamin produced in skin from the sun, and you have a preform of vitamin D that turns into Vitamin D - this vitamin D is inactive currently - to get activated, it has to go through hydroxylation reaction first in the liver and then in two different places, the kidney or other tissues of the body - when it happens in other tissues, they keep their vitamin d and their vitamin D plays a role for them in those tissues - when it goes to kidney it sends out to go do other things Vitamin D - calcium homeostasis helps to keep the blood levels of calcium in their normal range - the duodenal lumen is the small intestine, so this calcium that you get from a supplement or food, stimulates a protein and then helps to carry the calcium across from small intestine to blood stream 5 Vitamin D Deficiency: Rickets Children Failure of bones to calcify properly - if you do not get enough vitamin d you wont absorb enough calcium which can be absorbed in other ways - major way it is absorbed is through the vitamin D stimulated protein carrier - in children, their bones do not calcify properly and their bones have not completed in growth - osteomalacia: their bones are weak in adults - osteoporosis is a metabolic disease where the bone turnover is skewed towards the bone loss, as oppose to bone building Osteomalacia Adult form of rickets Osteoporosis Increased risk of fracture Vitamin D Deficiency/Toxicity Toxicity: - if you get too much vitamin d all these things can occur - you can also start absorbing too much calcium which will calcify soft tissues - you wont get toxic levels of vitamin D from the sun because there is a feedback loop - it comes from supplements where people taking too many •Nausea, vomiting •Loss of appetite •Calcification of soft tissues Other area of vitamin D research . . . Fall prevention Muscles have vitamin D receptors Vitamin D may play a role in muscle strengthening - vitamin D may play a role in making muscles stronger - Vitamin D could suppress the immune overreaction in type 1 diabetes helping preventing it - for type 2 it might increase insulin sensitivity so if you would not be as sensitive to insulin which might develop type 2 diabetes Types 1 & 2 Diabetes Prevention May suppress immune overreaction May increase insulin sensitivity Heart Disease Prevention Lower risk of multiple sclerosis 6 - major source of vitamin d is the sun and it hits our skin - pregnant woman more likely to be deficient than any one else but if they are deficient then their baby will be deficient American Academy of Pediatrics Babies, children, and teens needs 400 IU’s of vitamin D every day The old guideline was 200 IU’s Breastfed and partially breast-fed babies should be given 400 IU’s of vitamin D per day Talk to pediatrician about how to give your baby supplements safely If babies, children, or teens are not drinking 4 cups of milk/fortified juice a day, give them a supplement - breast milk is very low in vitamin D - ethnic groups like darker skin have more Vitamin D deficiency - as we age the skin gets thinner and when this happens there is less chemical tht converts vitamin d from the sun - sunscreen is at risk for vitamin deficiency as well Vitamin D recommendations Age Male Female Pregnancy Lactation 0–12 months* 400 IU (10 mcg) 400 IU (10 mcg) 1–13 years 600 IU (15 mcg) 600 IU (15 mcg) 14–18 years 600 IU (15 mcg) 600 IU (15 mcg) 600 IU (15 mcg) 600 IU (15 mcg) 19–50 years 600 IU (15 mcg) 600 IU (15 mcg) 600 IU (15 mcg) 600 IU (15 mcg) 51–70 years 600 IU (15 mcg) 600 IU (15 mcg) >70 years 800 IU (20 mcg) 800 IU (20 mcg) 7 - 15 to 20 mins, 3 days a week is the perfect amount of sun we need to not be Vitamin D deficient Few Food Sources of Vitamin D Food or Beverage Serving Size Vitamin D (IUs) Baked Herring 1 cup 3 oz 98 1,775 Baked Salmon 3 oz 238 Canned Tuna 3 oz 136 1 oz ¾ cup 77 31 1 25 Milk Sardines Raisin Bran Cereal Egg Yolk Should you supplement? • No more than 2000 IU’s a day unless physician recommended • Check all supplements: • Multivitamins = 400 to 1000 IU’s • Calcium +D supplements = 200 to 500 IU’s Vitamins Part 2: Fat Soluble Vitamins (E & K) BE T H KI T CHI N P H D RDN ASSI STANT PRO F ESSO R UAB DEPART M E NT O F NUT RI T I O N S CI E NCE S 8 - four forms of vitamin E, Alpha, beta, gamma, delta - the word tocopherole; that is a different word for it - vitamin E is necessary for reproduction in the human body which is the biggest function - the alpha - tocopherol form is the most active in the human body - vitamin E also protects us from substances called free radicals which are substances with unpaired electrons and they are just very unstable, can come from smoking, air pollution, sun - they can alter protein, inflammation, increase rate of aging - 9 Vitamin E Pharmacological Uses of Vitamin E - vitamin E is an antioxidant and blocks oxidation - it is a strong antioxidant and can find it in very high amount like in polyunsaturated fats - vitamin E and lowering risk of heart disease which had no correlation Has been recommended for: Heart disease prevention Cancer prevention Improved immune function What does the research show? - vitamin K1 is found in food sources - vitamin K2 is produced in body - vitamin K that is produced in the large intestine does not reall absorb well into the blood stream so it is not very bio available 10 Vitamin K Food Sources - leafy greens, cruciferous veggies (kale, cauliflower) - warfarin is a blood thinner that if you have a high risk of getti a heart attack - main function of vitamin k is to help our blood clot - it helps to convert the protein prothrombin into thrombin and then thrombin in turn turns around and catalyzes this reaction of fibrinogen to fibrin -if you get more vitamin K then whawt you should, then it can interfere with the blood thinner - little babies are at risk for hemorrhaging the first week after they are born and with this because they cannot produce vitamin K a it does not cross the placenta - takes a while for babies to build vitamin K - so they should get an injection of vitamin K when they are born 11 Vitamins Part 3: Water Soluble Vitamins BE T H KI T CHI N P H D RDN ASSI STANT PRO F ESSO R UAB DEPART M E NT O F NUT RI T I O N S CI E NCE S The B Vitamins Act as Coenzymes - as a b complex they act as coenzymes - b vitamins do not give us energy but they help us derive energy from our energy nutrients and they do it by acting as coenzymes in those energy cycles that enzymes can effectively catalyze reactions - more does not give you more energy TCA Cycle: Anabolic and Catabolic Reactions 12 The B-Vitamins Work Together Thiamin (B1) Sources: Whole/enriched grains Pork - b vitamins often work together - they play a role in the health of a tongue - a sign of vitamin B deficiency is glossitis and that is where the tongue becomes really smooth and swollen - cheilosis is another sign of b vitamin deficiency where the corner of the mouth becomes scaly - B1: thiamin - vegetable and plant sources - need a very little amount of thiamin - the deficiency disease is the wet beriberi disease - this is due to refined grains - now we enrich grains to avoid diseases such as these - enlarged heart, cardiac failure, are side effects from beriberi disease Legumes Riboflavin (B2) Sources: Whole/enriched grains Dairy - B2: Riboflavin - animal and plant sources and dairy foods - pretty abundant in our foods - the deficiency disease is called ariboflavinosis - inflammation of the mouth, skin, eyes - this vitamin is easily destroyed by light 13 Niacin (B3) Sources: Milk - deficiency disease is called pellagra - diarrea, dermatitis, dementia, and death are the four symptoms Whole/enriched grains Legumes Meat Vitamin B6 Folate/Folic Acid Daily Value = 400 mcg Deficiency: Increased homocysteine macrocytic (megaloblastic) anemia neural tube defects - meats and turkey - similar deficiencies and neurological symptoms with each sex - b complex vitamins - folate is the natural form you find in foods - folic acid is what you find in fortified foods and supplements - folic acid is better absorbed - macrocytic anemia (giant immature red blood cell) 14 Folate Daily Value: 400 mcg Food Mcg of Folate 1/2 cup chicken liver 539 ½ cup beef liver 185 ½ cup lentils 180 ½ cup fortified cereal 145-400 1 medium papaya 115 8 ounces orange juice 109 1 ounce wheat germ 100 4 spears cooked asparagus 88 ½ cup cooked turnip greens 85 ½ cup cooked spinach 54 ½ cup steamed broccoli 52 Vitamin B 12 - closely related to folate - due to absorbing it not necessarily intaking it Daily Value: 6 mcg Deficiency: pernicious anemia; smooth, sore tongue, fatigue, paralysis, skin hypersensitivity Sources: animal foods, fortified cereals, fortified soy products Deficiency usually due to poor absorption Atrophic gastritis Achlorhydria Lack of intrinsic factor - megaloblastic anemia - irregular shapes in folate and b12 deficiency 15 Vitamin C sources Food Mg of Vitamin C 1 large yellow pepper 341 1 large green pepper 120 1 cup orange juice 97 1 medium kiwi fruit 74 1 cup strawberries 84 ½ cup cooked broccoli 58 ½ cup cooked Brussels Sprouts 48 1 baked potato 31 1 baked sweet potato 28 ½ cup cooked cauliflower 28 ½ cup canned tomatoes 19 ½ cup cooked spinach 12 16 Saving Vitamin C Vitamin C can be lost from foods during preparation, cooking, or storage. To retain vitamin C: Serve fruits and vegetables raw whenever possible. Steam, boil, or simmer foods in a minimal amount of water, or microwave them for the shortest time possible. Cook potatoes in their skins. Refrigerate prepared juices and store them for no more than 2 to 3 days. Store cut raw fruits and vegetables in an airtight container and refrigerate--do not soak or store in water. Vitamin C will leach into the water. 17 ...
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