The Big Picture. Super Nutrients: Vitamins & Minerals Angeline B. David, DrPH, MHS NAD Health Summit March 14, What are Vitamins?

Transcription

1 The Big Picture Super Nutrients: Vitamins & Minerals Angeline B. David, DrPH, MHS NAD Health Summit March 14, 2013 Foods are composed of: Fats Carbohydrates Proteins Vitamins micro- Minerals nutrients Water Other compounds Phytochemicals VITAMINS What are Vitamins? Compounds available in foods that are essential for normal functioning Not made by host in adequate amounts Deficiency causes a specific syndrome May not be essential for all animals May not be necessary under all dietary or environmental conditions Types of Vitamins - 1 Fat-soluble Excess intake stored in fat cells Absorbed into lymphatic system Some excreted in bile Deficiencies are slow to develop Do not need to eat every day Some toxicity at relatively low levels Family of vitamins A, D, E, and K Types of Vitamins - 2 Water-soluble Excess intake are minimally stored Absorbed into blood Excreted in urine Deficiency symptoms develop quickly Must be eaten every day Usually toxic at relatively high levels Family of vitamins B & C

2 VITAMIN A Vitamin A First fat soluble vitamin discovered (1915) 3 types: retinol, retinal, retinoic acid Precursors: carotenoids 600+ have been identified Most common in diet: α-carotene*, β-carotene*, lycopene, lutein, zeaxanthin, β-cryptoxanthin* * = pro-vitamin A Vitamin A in Diet α-carotene and β-carotene green leafy vegetables, yellow-orange vegetables (sweet potato, squash), carrots, peaches, apricots, mango, papaya lycopene tomato, watermelon, pink grapefruit lutein green leafy vegetables, peas, green peppers, egg yolk zeaxanthin citrus fruit, maize (corn) Pre-formed Vitamin A only in animal foods; toxic in large amt Vitamin A Functions Vision transduction of light structure of eye Gene expression & cell viability Development Immune function VITAMIN D Vitamin D Steroid hormones Two types D2 - ergocalciferol Found in plants, fungi, molds, snails, worms D3 - cholecalciferol Formed when UVB radiation from sun activates 7-Dehydrocholesterol in skin D3

3 Vitamin D in Diet Vitamin D Functions Food sources include cod liver oil, salmon, egg Also fortified in milk Sun exposure is most important. Affected by season, latitude, time of day, cloud cover, smog, sunscreens, skin color, etc. Bone and muscle health: maintains normal levels of calcium and phosphorus by helping absorption of calcium Regulates immune function Regulates cell growth & development Regulates blood pressure & insulin VITAMIN E Vitamin E α-tocopherol Antioxidant: many exist, but only is considered to be Vitamin E 20-40% of dietary Vitamin E is absorbed Stored in fat tissue, liver, muscles Vitamin E Functions Vitamin E Antioxidant Stops chain reaction that leads to damaged cells throughout body Possible effects: Decrease risk of heart disease Improve immune response

4 VITAMIN K Vitamin K Three forms: K1 (plants), K2 (microorganisms), K3 (animals) Function: activates proteins for blood clotting and bone formation Regulate intake if on blood thinner medications (coumadin) Food sources: dark green leafy vegetables, vegetable oils, soybean, lentils, very low in meats Vitamin K B VITAMINS Vitamin B1: Thiamin Vitamin B1: Thiamin Quickly destroyed by heat, leaches out in cooking water Assists function of enzymes Component of neuronal membranes in nerve and brain Deficiencies: neurologic (paralysis of eye nerve, stiff walking, impaired cognitive function), beriberi, encephalopathy

5 Vitamin B2: Riboflavin Vitamin B2: Riboflavin Not destroyed by heat, but very sensitive to light Assists function of enzymes Deficiency: swollen lips & tongue, oily skin, loose taste buds, increases cataracts formation, migraine attacks Niacin Can be made in body from tryptophan Made mostly in liver so also need dietary source Stable in storage and cooking Functions: assists enzymes, formation of proteins, gene stability Deficiency: pellagra (diarrhea, dermatitis, dementia, death, scarlet tongue) Niacin Vitamin B6 Vitamin B6 Family of compounds Acidic solution protects from heat Processing results in 10-50% loss of B6 Functions: assist 100 enzymes, red blood cell formation, synthesis of neurotransmitters, supports immune system Deficiency: greasy skin, dizziness, nausea, insomnia, irritability, confusion, convulsions, anemia Prone in alcoholics, elderly, liver disease patients

6 Folic Acid Alternative name: folate Supports activity for making DNA & RNA Deficiency: megaloblastic (large) red blood cells and bone marrow cells, no cell division, sore red tongue, abnormal white blood cells, anemia Neural tube defects Linked with Vitamin B12 deficiency Folic Acid Vitamin B12: Cyanocobalamin Function: assists enzyme reactions, health of nerve and red blood cells, supports making DNA Deficiency: megaloblastic anemia (large red blood cells) neurologic changes: numbness in fingers and toes, unsteadiness, poor muscle coordination, forgetfulness, moodiness, mental slowness, poor memory, confusion, agitation, depression, delusions, hallucinations, psychosis, paranoia Causes: inadequate intake, poor absorption, metabolic disorders Vitamin B12 Absorption In food, B12 is bound to protein (free in supplements) Stomach acids separate protein and B12 Intrinsic Factor (IF) released into stomach and binds B12 IF-B12 complex absorbed by terminal cells of small intestine B12 is released by IF then enters blood stream Vitamin B12 Absorption Amount absorbed is influenced by amount eaten: eat more! absorb less Maximum absorbed: 5 micrograms RDA = 2.4 micrograms per day (adults) Elderly have lower absorption due to less stomach acids to free B12 from food proteins Vitamin B12 Storage 80% of absorbed B12 put in storage Adult stores can be 2-3 milligrams About 0.5 micrograms are lost per day High stores can take years to deplete Total vegetarians & elderly at higher risk Fortified foods or supplements if older than 50 years of age

7 Vitamin B12: Cyanocobalamin ** Also look for fortified foods (soy milk, cereals, etc) Biotin In foods, bound to protein Made by bacteria in intestinal tract Avidin (protein in raw egg white) prevents biotin absorption Functions: supports enzymes, gene expression, normal cell cycle Deficiency: decrease pancreatic secretions, dermatitis, conjunctivitis, hair loss Biotin Food Sources Pantothenic Acid Egg yolk Liver Vegetables Walnuts Component of Coenzyme A (CoA) Functions: synthesis of phospholipids, steroids, and fatty acids Deficiency: burning foot syndrome, vomiting, malaise, abdominal pain, cramps, fatigue, insomnia, etc Chicken Beef Potatoes Oat cereals Pantothenic Acid Food Sources Tomato products Yeast egg yolk Broccoli Whole grains Royal bee jelly Choline Functions Cell membrane integrity & signal transduction Source of methyl groups for other reactions Neurotransmitter Lipid transport and metabolism Apoptosis (cell death) Deficiency: fatty liver (animals), decreased LDL and HDL, brain malformation, carcinogenesis

8 Choline VITAMIN C Vitamin C Essential for humans and handful of animals First identified in 1753 as curing scurvy among British sailors Primary forms: ascorbic acid, dehydroascorbic acid (both cure scurvy) Maximum of 2 grams stored in body Excess is excreted by kidneys or in stool Vitamin C Functions: supports enzyme function, antioxidant, improves iron absorption, regulate gene expression, protects DNA, prevents formation of harmful radicals and Nitrogen compounds Deficiency: scurvy (swollen limbs, edema, impaired wound healing, weakness, psychologic and neurologic problems), bleeding gums, orbit of eyes, and nail beds Excess (>1g/day): diarrhea, nausea, bloating Vitamin C

9 MINERALS Minerals Inorganic compounds (no Carbon atom) Essential macro-minerals - need >100 mg/day Calcium, phosphorus, potassium, magnesium, sodium, sulphur Essential micro/trace-minerals - need <100 mg/day Cromium, cobalt, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, zinc All have an optimal range of intake & are toxic in excess Functions of Minerals Structure: bone, teeth, tissues, etc Act with enzymes, hormones, other compounds in body Support action of nervous system, muscle contraction, regulates acidity and fluid in cells Influence bone: calcium, magnesium, phosphorus, fluoride, [Vitamin D], boron, manganese, silicon Influence immunity: iron, zinc, copper CALCIUM Calcium (Ca) 99% found in bone + 1% in muscle + 0.2% in blood If blood levels drop, body will compensate by: Increase Ca absorption from food Increase Ca reabsorption via kidney Remove Ca from bone stores Ca & Other Nutrients Vitamin D: necessary to absorb Ca from food Protein: not conclusive that it effects Ca absorption Phosphorus: not conclusive that it decreases Ca absorption Caffeine: short-term increase in Ca loss Sodium: increases Ca loss Potassium: increases Ca retention

10 Calcium (Ca) ZINC Zinc (Zn) Important for growth & development Incorporated into muscle, bone, skin, liver, brain, kidneys, heart, hair, blood Phytic acid (whole grains, legumes), oxalic acid (vegetables), and fiber decrease Zn absorption from food Phytic acid deactivated by yeast Effect of oxalic acid may be minimal Zinc (Zn) Deficiencies Growth retardation Delayed sexual maturation Hair loss Diarrhea Eye & skin lesions Poor wound healing Impaired taste sensation Excess intake (1-2 g/d)! sideroblastic anemia Zinc (Zn) IRON

11 Iron (Fe) Iron found in blood cells, muscle cells, linked with other compounds Deficiency: anemia Two dietary forms Heme - found in meat Easily absorbed Non-heme - found in cereals, vegetables, legumes, fruits, etc Increase absorption with Vitamin C IODINE Iodine (I) Plants absorb iodine from soil-- soil may be deficient in high altitudes Iodine is component of thyroid hormones Deficiency: goiter, cretinism, stillbirth, abortion, congenital malformation Food-based intervention Iodized salt, fortify other foods CHROMIUM Chromium (Cr) Health benefits: improves glucose tolerance, increase insulin action, prevent heart attack, decrease blood lipids Food sources Widely found in food supply Whole grains better than refined Brewer s yeast Increase absorption with Vitamin C Refined sugars increase excretion of Cr Dietary supplements are poorly absorbed and may result in DNA damage Chromium (Cr)

12 COPPER Copper (Cu) Deficiency is usually not due to lack in diet Functions: connective tissue, central nervous system, cardiac function, regulate cholesterol levels, immune function Plant foods provide over 60% of dietary Cu in Americans Copper (Cu) MAGNESIUM Magnesium (Mg) Acts with over 300 different enzyme systems Deficiency: muscle cramps & spasms, hypertension, heart and brain vasospasm, psychological & mood changes, memory problems, depression, confusion, etc. Magnesium (Mg)

13 MANGANESE Manganese (Mn) Functions: activates enzymes for collagen formation, bone development, wound healing, metabolism of carbohydrates, proteins, and cholesterol Deficiency: dermatitis Toxicity: central nervous system Manganese (Mn) SELENIUM Selenium (Se) Selenium (Se) Bound to proteins found throughout the body Deficiency: Keshan disease (cardiomyopathy), Kashin-Beck disease (osteoarthritis, cartilage breakdown) Toxicity: Loss of hair, nails, skin lesions, tooth decay, nervous system abnormality

14 VANADIUM Vanadium (V) Health effect: mimics insulin, may lower blood sugar and LDL cholesterol Toxic at doses > 1.8 mg/day Food sources: mushrooms, shellfish, black pepper, parsley, dill weed, grain and grain products, and artificially sweetened drinks