Vitamins Lecture 7 PDF

VITAMINS LECTURE 7 Subtitle 1  LEARNING OBJECTIVES: ▪ Identify the meaning of vitamins ▪ Compare fat-soluble vitamins with water-soluble vitamins. ▪ Discuss the roles, food sources, function, and consequences of deficiency and toxicity of fat-soluble vitamins...

VITAMINS LECTURE 7 Subtitle 1  LEARNING OBJECTIVES: ▪ Identify the meaning of vitamins ▪ Compare fat-soluble vitamins with water-soluble vitamins. ▪ Discuss the roles, food sources, function, and consequences of deficiency and toxicity of fat-soluble vitamins. ▪ Discuss the roles, food sources, function, and consequences of deficiency and toxicity of water-soluble vitamins. 2 WHAT ARE VITAMINS ? ▪ Vitamins are essential, noncaloric organic nutrients, required in small amounts. ▪ Vitamins do not supply energy ▪ They cannot be synthesized by the body. Must be obtained by outside sources like diet, rumen bacteria & sun. ▪ Unlike carbohydrates, proteins, and fats; vitamins are individual units, they are not linked together. ▪ Required for growth, maintenance, reproduction, and lactation. 3  CLASSIFICATION OF VITAMINS ▪ Fat Soluble Vitamins ( A, D, E, K ) ▪ Water Soluble Vitamins ( C and B Complex ) 4  Water - Soluble Fat- Soluble Vitamins Vitamins CHARACTERISTICS Absorption Absorbed into lymph and Absorbed directly into then into the blood. the blood Transport and storage Travel in the blood with protein carriers; stored in Travel freely in watery fluids; most are not OF THE FAT- the liver or fatty tissues. stored in the body. SOLUBLE AND Excretion Not readily excreted; tend to Readily excreted in WATER-SOLUBLE build up in the tissues. the urine. VITAMINS Toxicity More likely from Unlikely but possible supplements but occur with high doses from rarely from food supplements. Requirements Needed in periodic doses( Needed in frequent weeks or months) doses( 1 to 3 days) 5 FAT-SOLUBLE VITAMINS ▪ Fat- Soluble vitamins play diverse roles in the body. ▪ Vitamins A and D, act as hormones ▪ Vitamin E protects tissues from destructive oxidative reactions. ▪ Vitamin K is necessary for blood clotting and bone health. 6  VITAMIN A ▪ Vitamin A is a group of similar compounds called retinoids. ▪ There are 3 forms of vitamin A found in animal foods and stored in the liver 1. retinol: a most active form 2. Retinal 3. retinoic acid 4. Also, About 10 percent of plant-derived carotenoids, including beta- carotene, can be converted in the body into retinoids(another source of functional vitamin A.) ▪ Carotenoids are pigments synthesized by plants that give them their yellow, orange, and red color. 7 FUNCTIONS OF VITAMIN A ▪ Vision ▪ (Retinol ) Generates pigments for the retina ▪ Maintains the coverings and linings of the eyes ▪ )Retinoic acid( Regulation of gene expression(Reproduction) ▪ Required for cell growth and division-epithelial cells, bones, and teeth ▪ Promotes the development of immune cells ▪ Healthy Skin 8  VITAMIN A RECOMMENDATION AND SOURCES ▪ The DRI for vitamin A is based on body weight. ▪ For man: needs about 900 micrograms of active vitamin A ▪ For woman: needs about 700 micrograms, during lactation needs higher ▪ Food Sources: ▪ Animal Sources (Eggs, Meat, Cheese, Milk, Liver, Kidney) Plant Sources (Carrots, Sweet Potatoes, Pink Grapefruit, Apricots, Broccoli, Spinach, Pumpkin) The human body converts all dietary sources of vitamin A into retinol. 9 Signs of Deficiency: Night blindness, exophthalmia Decreased resistance to infections Extremely dry skin, hair, or nails Anemia retarded growth in children 10  Toxicities: Single large doses of supplements, eating excessive amounts of liver ▪ Symptoms: ▪ Dry, itchy skin, headaches, fatigue, hair loss,, blurred vision, loss of appetite, swelling of the brain, joint pain, and skin coloration ▪ In severe cases, vitamin A toxicity may cause liver damage and coma ▪ Other Side Effects: ▪ Excessive vitamin A during pregnancy can injure the heart, spinal cord, and other tissues of the developing fetus, causing birth defects 11  VITAMIN E: ▪ Vitamin E occurs in eight chemical forms. ▪ Alpha-tocopherol is the only form that is recognized to meet human requirements. ▪ Functions: ▪ Antioxidant ▪ Stop the forming of free radical ▪ Discourage the development of some types of cancer ▪ Necessary for normal nerve development ▪ Promotes normal growth and development ▪ Inhibiting the formation of blood clotting. ▪ Aids the process of wound healing ▪ Boosts the immune system 12 VITAMIN E RECOMMENDATION AND SOURCES Sources: Recommendation: Wheat germ oil, vegetable oils, 15 milligrams a day for adults. nuts and seeds, whole grains, egg yolk, leafy green vegetables. ▪ Vitamin E is easily destroyed by heat. 13  VITAMIN E DEFICIENCY ▪ Insufficient levels are rare but most likely when diets are extremely low in fat for years. ▪ People at high risk: ▪ People with malabsorption disorders, such as Crohn’s disease or cystic fibrosis, ▪ babies born prematurely, are at higher risk for vitamin E deficiency. ▪ Deficiency Symptoms: Toxicities: (more than 1000 milligrams/day) ▪ Red blood cell breakage Augments the effect of anti-clotting ▪ Nerve damage medication ▪ Loss of muscle coordination ▪ Impaired vision and speech 14  VITAMIN K : ▪ Produced by bacteria in the large intestine Function: Promotes synthesis of blood clotting Bone formation Deficiency Symptoms: ▪ Hemorrhaging ▪ Deficiencies are rare but seen in infants, after prolonged antibiotic therapy, and in patients with decreased bile production. 15 VITAMIN K : Toxicity Symptoms (>1000 mg/day): None known Sources: ▪ Bacterial synthesis in the digestive tract, Milk, Liver, Leafy green vegetables, cabbage-type vegetables ▪ Recommendation: ▪ For men: 120 micrograms a day ▪ For women: 90 micrograms a day 16 VITAMIN D ▪ Vitamin D refers to a group of fat-soluble vitamins derived from cholesterol ▪ The skin synthesizes vitamin D when exposed to sunlight. ▪ Vitamin D is not an essential nutrient. ▪ Factors that decrease the synthesizes of vitamin D: ▪ Season ( Long winter) ▪ Wearing sunscreen ▪ The color of the skin (dark-skinned people need more time for sun exposure) ▪ Time ( Vitamin D3 synthesis increases in the morning) ▪ Age ( Old people) ▪ Clothing (Wearing full clothing that covers the skin) ▪ Using sunscreen 17  Function: Is essential for the proper utilization of calcium and phosphorus to produce normal, healthy bones. Play a role in muscle function and the immune system VITAMIN D Might help prevent colon, prostate and breast cancers Might help prevent and treat diabetes, heart disease, high blood pressure, and multiple sclerosis. 18 DEFICIENCY DISEASES: ▪ Rickets (Children develop bowed legs) ▪ Osteomalacia (Adults, their bones become soft, flexible, weak, and deformed) ▪ Toxicities: ▪ Increase blood calcium ▪ Calcification of soft tissues (blood vessels, kidneys, heart, lungs, tissues around joints) ▪ Loss of appetite, nausea, vomiting, frequent urination, fatigue, back pain, and irregular heartbeat. 19 VITAMIN D Sources: ▪ Synthesized in the body with the help of sunlight. ▪ Less than thirty minutes of sun exposure to the arms and legs will increase blood levels of vitamin D3 ▪ Fortified milk, margarine, butter, cereals, beef, egg yolk, liver, fatty fish ▪ Vitamin D Intake recommendation: ▪ People ages 1 to 70 years old need 15 micrograms of vitamin D daily. ▪ 71 and older, need 20 micrograms per day. 20 WATER SOLUBLE VITAMINS 21 VITAMIN C (ASCORBIC ACID): ▪ Functions: ▪ Protects the body from free radicals ▪ Helps form connective tissue that holds bones, muscles, and tissues together (collagen) ▪ Aids in the healing of wounds ▪ Aids the body in absorbing iron from plant sources ▪ Helps to keep gums healthy ▪ Helps the body to fight infections ▪ Aids in the prevention of heart disease 22 ▪ Deficiency signs: ▪ Scurvy ( Bleeding gums, loosened teeth, swollen ankles and wrists, and tiny red spots in the skin) ▪ fatigue and joint pain ▪ reduced resistance to colds and infections ▪ slow healing of wounds and fractured bones ▪ Anemia ▪ Toxicity Symptoms: over 1000mg/ dose ▪ Nausea, abdominal cramps, diarrhea ▪ Headache, fatigue, insomnia ▪ Rashes ▪ Urinary tract problems, kidney stones 23  Citrus fruits (oranges, grapefruits, lemons, limes). Cabbage-type vegetables; Dark green vegetables (such as Sources: broccoli) Strawberries and other berries, cantaloupe and other melons, papayas, mangoes, potatoes, and tomatoes, Guava. Recommended Men: 90 mg/day Dietary Intake Women: 75 mg/day Smokers: +35 mg/day RDI: Upper Level Adults: 2,000 mg/day 24 ▪ B Complex: (Thiamin B1, Riboflavin B2, Niacin B3, Folate B9, B6, B12, Biotin B7, and Pantothenic acid). Functions: ▪ Aid in the metabolism of energy released from carbohydrates, lipids, and amino acids and help the body use this energy. ▪ Part of coenzymes that combines with an enzyme and activates it. 25  Thiamin B1: Function It is important in glucose metabolism. It acts as a cofactor for enzymes that break down glucose for energy production. plays a role in the synthesis of neurotransmitters required for RNA, DNA, and ATP synthesis. Food Sources Whole-grain, fortified, or enriched grain products Moderate amounts in all nutritious food Toxicity Symptoms None reported 26  DEFICIENCY DISEASE ▪ 1. Beriberi ▪ 2. Wernicke Korsakoff syndrome ▪ Tow types ( wet with edema; dry with ▪ Confusion muscle wasting) ▪ loss of coordination ▪ Fatigue ▪ vision changes ▪ Confusion ▪ hallucinations ▪ movement impairment ▪ may progress to coma and death ▪ pain in the lower extremities, swelling ▪ heart failure. ▪ This condition is specific to ▪ This condition is common in societies alcoholics as diets high in alcohol whose main dietary staple is white rice. 27  RIBOFLAVIN B2: ▪ Function ▪ Riboflavin is an essential component of flavoproteins, which are coenzymes involved in many metabolic pathways of carbohydrate, lipid, and protein metabolism. ▪ The “flavin” portion of riboflavin gives a bright yellow color to riboflavin ▪ Food Sources ▪ Milk and dairy products (yogurt, cheese). ▪ Enriched or whole grains ▪ Liver 28 Deficiency Cracks and redness at the corners of the mouth Sore throat Hypersensitivity to light. Itching and burning eyes. Dry, scaly skin Recommendation DRI: Men: 1.3 mg/ day Women: 1.1 mg/day NIACIN B3 ▪ Like thiamin and riboflavin, participates in the energy metabolism of every cell. ▪ Food Sources ▪ Amino acid Tryptophan which is abundant in almost all proteins, is converted to niacin in the body. ▪ In plants, especially mature grains ▪ Deficiency Disease ▪ Pellagra, its symptoms are known as the four “Ds”: (Diarrhea, Dermatitis, Dementia, and Death ) 30  VITAMIN B6 (PYRIDOXINE) ▪ Vitamin B6 is the coenzyme involved in a wide variety of functions in the body. ▪ Function ▪ Part of a coenzyme needed in amino acid and fatty acid metabolism ▪ Essential for the conversion of amino acid methionine into cysteine. ▪ Helps convert tryptophan to niacin and serotonin ▪ Helps make hemoglobin. ▪ Assist in releasing stored glucose from glycogen ▪ Develops the brain and nervous system of a fetus. 31 Deficiency symptoms ▪ Weakness, depression, confusion, irritability, convulsions, insomnia, and greasy dermatitis ( the skin is greasy and flaky). ▪ Food Sources ▪ Meat, fish, and poultry(protein-rich food) ▪ Starchy vegetables and fruits. ▪ Potatoes and leafy green vegetables. 32 FOLATE B9: ( FOLIC ACID ) ▪ Function: ▪ required for making RNA and DNA. ▪ Works with vitamin B12 to form hemoglobin in red blood cells ▪ Folate is a required coenzyme for the synthesis of the amino acid methionine ▪ Helps prevent neural tube defects, such as spina bifida which occurs when the spine does not completely enclose the spinal cord ▪ Deficiencies: ▪ Anemia (large-cell type) ▪ Smooth, red tongue ▪ Mental confusion, weakness, fatigue, irritability, headache 33 FOLATE B9: ( FOLIC ACID ) ▪ Food Sources: ▪ Fortified grains, Leafy green vegetables, Legumes, seeds, Liver Recommendation: ▪ DRI 400 milligrams/day 34 VITAMIN B12 (COBALAMIN) ▪ Vitamin B12 contains cobalt, making it the only vitamin that contains a metal ion. ▪ In order for the human body to absorb vitamin B12, the stomach, pancreas, and small intestine must be functioning properly. ▪ Cells in the stomach secrete a protein called intrinsic factor that is necessary for vitamin B12 absorption, which occurs in the small intestine ▪ Functions: ▪ Part of coenzymes that are used in new cell synthesis ▪ Helps to maintain nerve cells ▪ Helps to break down some fatty acids and amino acids ▪ Essential for hemoglobin synthesis ▪ Help to convert folate to active form. 35 VITAMIN B12 (COBALAMIN) Deficiency Deficiency Disease: Symptoms Pernicious anemia Anemia, Fatigue, Large and Paralysis, Nerve immature red damage in the blood cells fetus 36  Toxicity None reported Symptoms Animal products (meat, poultry, Food Sources : fish, shellfish, milk, cheese, eggs) Fortified cereals 37 ▪thank you 38