1. © 2011 Pearson Education, Inc. 12 Nutrients Involved in Blood Health and Immunity

2. © 2011 Pearson Education, Inc. Blood Functions Transports nutrients and oxygen to cells Removes waste products generated from metabolism

3. © 2011 Pearson Education, Inc. Components of Blood Erythrocytes—red blood cells transport oxygen through the body Leukocytes—white blood cells are key to our immune system Platelets—cell fragments assist in blood clotting Plasma—fluid portion of the blood maintains adequate blood volume

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5. Nutrients Maintain Healthy Blood Iron Zinc Copper Vitamin K Folate Vitamin B 12

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7. Iron Iron is a trace mineral Component of oxygen-carrying hemoglobin and myoglobin (muscle) Component of cytochromes, electron carriers within the metabolic pathways for energy production from carbohydrates, fats, and protein

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9. Maintaining Iron Homeostasis Regulation of iron digestion, absorption, transport, storage, and excretion Factors that alter iron digestion and absorption Individual’s iron status Level of dietary iron consumption Type of iron in foods Amount of stomach acid for digestion Dietary factors enhance or inhibit absorption

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11. Iron Two types of iron in foods Heme iron—found only in animal-based foods and more absorbable Non-heme iron—not as easily absorbed

12. © 2011 Pearson Education, Inc. Iron Factors that promote iron absorption Meat factor Stomach acids Vitamin C

13. © 2011 Pearson Education, Inc. Iron Factors that impair iron absorption Phytate (legumes, rice, and whole grains) Polyphenols (oregano, red wine, tea, coffee) Vegetable proteins Fiber Calcium Bioavailability of iron from vegan diet is 10%, vs. typical Western diet’s 14−18%

14. © 2011 Pearson Education, Inc. Iron Iron transport Transferrin: iron-transport protein in blood Receptors on cells transport iron into cells Iron storage Ferritin and hemosiderin help meet iron needs Liver, bone marrow, and spleen

15. © 2011 Pearson Education, Inc. Iron Regulation of total-body: Iron absorption Iron losses Storage and recycling of iron

16. © 2011 Pearson Education, Inc. Iron Recommended intake RDA varies based on age and gender 8 mg/day for adult men 18 mg/day for adult women,19−50 years 27 mg/day for pregnant women Sources of iron Meat, poultry, fish, clams, oysters, liver, enriched or fortified cereals and breads Supplements

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18. Too Much Iron Accidental iron overdose: most common cause of poisoning deaths in children Symptoms: nausea, vomiting, diarrhea Hemochromatosis: excessive absorption of dietary iron and altered iron storage Treatment: reduce dietary iron, avoid high vitamin C intake, blood removal

19. © 2011 Pearson Education, Inc. Not Enough Iron Most common nutrient deficiency in the world High risk: infants, young children, adolescent girls, premenopausal and pregnant women Poor dietary intakes Iron losses in blood and sweat Diets high in fiber or phytates that bind iron Low stomach acid Poor iron absorption (poor gut health or dietary supplements with high mineral levels, e.g., calcium)

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21. Stages of Iron Deficiency 1.Iron depletion is caused by a decrease in iron stores 2.Iron-deficiency erythropoiesis occurs with decreased iron transport 3.Iron-deficiency anemia results in reduced normal, healthy red blood cell production, decreased size, inadequate hemoglobin

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23. Zinc Zinc is a trace mineral Functions of zinc Component of enzymes (heme synthesis) Maintain structural integrity and shape of proteins Assist in regulating gene expression

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25. Zinc Absorption increases with need: growth, sexual development, pregnancy Dietary factors inhibit zinc absorption High non-heme iron intake Phytates and fiber (whole grains, beans) Dietary factor enhances zinc absorption Animal-based protein

26. © 2011 Pearson Education, Inc. Zinc RDA: 8 mg/day for women, 11 mg/day for men Sources of zinc Red meats, some seafood, whole grains, enriched grains and cereals

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28. Zinc Too much zinc Toxicity can occur from supplements Symptoms: intestinal pain, cramps, nausea, vomiting Depressed immune function Decreased high-density lipoprotein concentrations Interference with copper and iron absorption.

29. © 2011 Pearson Education, Inc. Zinc Not enough zinc Deficiencies are uncommon in the United States Symptoms: growth retardation, diarrhea, delayed sexual maturation, hair loss, impaired appetite, infections Lack of good assessment parameters for zinc

30. © 2011 Pearson Education, Inc. Copper Copper is a trace mineral Functions of copper Required for iron transport Cofactor in energy metabolism and for connective tissue production Part of superoxide dismutase antioxidant enzyme system Regulates neurotransmitters (serotonin)

31. © 2011 Pearson Education, Inc. Copper Factors that promote copper absorption More copper is absorbed with low-copper diet Factors that impair copper absorption High zinc intakes High iron intakes

32. © 2011 Pearson Education, Inc. Copper Recommended intake RDA for adults is 900 µg/day Sources of copper Organ meats, seafood, nuts, seeds, whole-grain foods

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34. Copper Too much copper Toxicity is not well studied in humans Symptoms: abdominal pain, nausea, diarrhea, vomiting, liver damage (Wilson disease) Not enough copper Copper deficiency is rare Symptoms: anemia, reduced white blood cells, osteoporosis (children—bone demineralization)

35. © 2011 Pearson Education, Inc. Vitamin K Vitamin K is a fat-soluble vitamin important for both bone and blood health Function of vitamin K Coenzyme assists in synthesizing blood coagulating proteins: prothrombin and procoagulants, factors VII, IX, and X

36. © 2011 Pearson Education, Inc. Vitamin K Factors that promote vitamin K absorption Gastrointestinal bacteria produce vitamin K Dietary need depends on intestinal health Factors that impair vitamin K absorption Impaired dietary fat absorption

37. © 2011 Pearson Education, Inc. Vitamin K Recommended intake AI for adults is 90−120 µg/day Sources of vitamin K Green leafy vegetables, such as collard greens, kale, spinach, cabbage Soybean and canola oils

38. © 2011 Pearson Education, Inc. Vitamin K Too much vitamin K No known side effects Not enough vitamin K Deficiency is rare Blood fails to clot, bleeding, hemorrhaging Fat malabsorption Newborns lack intestinal bacteria to produce vitamin K (injection at birth)

39. © 2011 Pearson Education, Inc. Folate Folate is a water-soluble vitamin Functions of folate (coenzyme) DNA synthesis, amino acid metabolism Cellular division and differentiation Functions with B 12 and B 6 metabolism

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41. Folate Factors that alter folate digestion, absorption, and balance Bioavailability depends on its source: better from supplements than from food Alterations in folate status mimic those of iron Four states of folate deficiency

42. © 2011 Pearson Education, Inc. Folate Recommended intake RDA : 400 µg/day adults, 600 µg/day during pregnancy Sources of folate Fortification to minimize birth defects: enriched breads, flours, pasta, grain products Liver, spinach, lentils, oatmeal, asparagus Heat-sensitive; leached out in cooking liquid

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44. Folate Too much folate Toxicity can result from supplements Toxicity can mask vitamin B 12 deficiency Symptoms: intestinal pain, nausea, vomiting Not enough folate Macrocytic anemia Elevated homocysteine Neural tube defects

45. © 2011 Pearson Education, Inc. Vitamin B 12 Vitamin B 12 is a water-soluble vitamin Functions of vitamin B 12 Coenzyme for DNA synthesis Maintains myelin sheath of nerve fibers Metabolism of amino acid homocysteine

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47. Vitamin B 12 Factors that alter vitamin B 12 digestion, absorption, and balance Requires acidic environment (stomach) and protein intrinsic factor for absorption Stored in the liver Four levels of vitamin B 12 deficiency Vitamin B 12 Absorption

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49. Vitamin B 12 Recommended intake RDA for adults is 2.4 µg/day Sources of vitamin B 12 Available exclusively from animal sources Vegan diet may obtain vitamin B 12 from fortified foods, supplements, or injections

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51. Vitamin B 12 Too much vitamin B 12 No known adverse effects Not enough vitamin B 12 Deficiency is rare, but associated with dietary insufficiency or reduced absorption Gastrointestinal and neurologic effects Pernicious anemia (lack intrinsic factor)

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53. Neural Tube Defects Folate is required for cell division and proper formation of the neural tube (develops into brain and spinal cord) Increased early need for folate All women capable of becoming pregnant should consume an additional 400  g of folate daily

54. © 2011 Pearson Education, Inc. Vascular Disease Folate and vitamin B 12 are required for the breakdown of amino acid homocysteine Low folate and vitamin B 12 intake may increase the level of homocysteine High homocysteine levels are associated with risk for vascular disease Adequate folate, vitamin B 6, vitamin B 12 may reduce risk for heart attack or stroke

55. © 2011 Pearson Education, Inc. Anemia Anemia (“without blood”)—low hemoglobin Genetic (sickle cell anemia, thalassemia) Microcytic anemia: low iron or vitamin B 6 Macrocytic anemia: low vitamin B 12 or folate Pernicious anemia: low vitamin B 12

56. © 2011 Pearson Education, Inc. Immune System A healthy immune system Protects the body from infectious diseases Helps heal wounds Guards against the development of cancers How does it function? Nonspecific immune function Specific immune function

57. © 2011 Pearson Education, Inc. Nonspecific Immune System Body’s primary defense against microbes, airborne particles, venom, ingested toxins Also called innate immunity Intact skin and healthy mucous membranes Stomach acid destroys food-borne bacteria Inflammatory response causes discomfort, loss of appetite, fatigue, and fever

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59. Specific Immune System Directed against recognized antigens Induces antibodies to destroy invader Memory cells remain in circulation Two main types of cells: B cells and T cells Acquiring specific immunity Have disease or vaccinations (immunizations) Maternal antibodies Antiserum injection (snakebite)

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61. Immune System Malfunction causes chronic inflammation and infection Allergic reactions Autoimmune response Common in malnourished Immune deficiency diseases

62. © 2011 Pearson Education, Inc. Nutrition A nourishing diet provides all the nutrients the immune system needs Single-nutrient subclinical deficiencies can cause subtle abnormalities in immunity Protein-energy malnutrition and severe micronutrient deficiencies reduce immune function

63. © 2011 Pearson Education, Inc. Protein-Energy Malnutrition Malnutrition increases the risk for infection Infection depresses appetite and often causes vomiting and diarrhea Decreased appetite, vomiting, and diarrhea cause malnutrition, which increases vulnerability to infection Decreased immunocompetence is a sensitive indicator of reduced nutritional status

64. © 2011 Pearson Education, Inc. Overnutrition/Obesity Increases incidence of infections Delays wound healing Poor antibody response to vaccination Inflammatory state may increase asthma, hypertension, cardiovascular disease, and type 2 diabetes among obese individuals

65. © 2011 Pearson Education, Inc. Essential Fatty Acids Essential fatty acids are precursors for signaling molecules eicosanoids Omega-6 fatty acids promote inflammatory response to help contain infection Omega-3 fatty acids diminish inflammation in blood vessels (prevent heart disease)

66. © 2011 Pearson Education, Inc. Vitamins and Minerals Vitamin A maintains mucosal surface Vitamins C and E protect cell membrane from reactive oxygen species Zinc assists immune cell gene expression and enzyme activation (B and T cell proliferation)

67. © 2011 Pearson Education, Inc. Vitamins and Minerals Copper: growth factor for immune cells Iron deficiency impairs immune function Selenium: Coenzyme for glutathione peroxidase Promotes B and T cell proliferation Antibody production Excessive amounts can impair immunity