Nutrients Involved in Blood Health and Immunity

1. 12 Nutrients Involved in Blood Health and Immunity

2. Blood • Functions • Transports nutrients and oxygen to cells • Removes waste products generated from metabolism

3. 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

5. Nutrients Maintain Healthy Blood • Iron • Zinc • Copper • Vitamin K • Folate • Vitamin B12

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

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

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. Iron • Factors that promote iron absorption • Meat factor • Stomach acids • Vitamin C

13. 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. 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. Iron • Regulation of total-body: • Iron absorption • Iron losses • Storage and recycling of iron

16. 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

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. 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)

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

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

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. 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

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. 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. 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. 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. Copper • Recommended intake • RDA for adults is 900 µg/day • Sources of copper • Organ meats, seafood, nuts, seeds, whole-grain foods

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. 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. 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. 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. 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. Folate • Folate is a water-soluble vitamin • Functions of folate (coenzyme) • DNA synthesis, amino acid metabolism • Cellular division and differentiation • Functions with B12 and B6 metabolism

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. 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

44. Folate • Too much folate • Toxicity can result from supplements • Toxicity can mask vitamin B12 deficiency • Symptoms: intestinal pain, nausea, vomiting • Not enough folate • Macrocytic anemia • Elevated homocysteine • Neural tube defects

45. Vitamin B12 • Vitamin B12 is a water-soluble vitamin • Functions of vitamin B12 • Coenzyme for DNA synthesis • Maintains myelin sheath of nerve fibers • Metabolism of amino acid homocysteine

47. Vitamin B12 • Factors that alter vitamin B12 digestion, absorption, and balance • Requires acidic environment (stomach) and protein intrinsic factor for absorption • Stored in the liver • Four levels of vitamin B12 deficiency Vitamin B12 Absorption

49. Vitamin B12 • Recommended intake • RDA for adults is 2.4 µg/day • Sources of vitamin B12 • Available exclusively from animal sources • Vegan diet may obtain vitamin B12 from fortified foods, supplements, or injections