Chapter 12 Nutrients Involved in Blood Health and Immunity What Is the Role of Blood in Maintaining Health Transports nutrients and oxygen removes the waste products generated from metabolism so that they can be properly excreted Erythrocytes red blood cells o Transport oxygen Leukocytes white blood cells o The key to our immune function and protect us from infection and illness Platelets cell fragments Plasma fluid portion of blood body o Assist in the formation of blood cloths and help stop bleeding o Need to maintain adequate blood volume so that blood can flow easily throughout the A Profile of Nutrients That Maintain Healthy Blood Iron zinc copper vitamin k folate and vitamin b 12 Trace mineral The most common nutrient deficiency in the world Ferrous iron fe 2 to ferric iron fe 3 Functions Iron o Hemoglobin the oxygen carrying protein found in the erythrocytes o Myoglobin another oxygen carrying protein that is similar to hemoglobin transports and stores oxygen within the muscles accounting for approximately 10 of total iron in the body o Cytochromes electron carriers within the metabolic pathways that result in the production of energy from carbohydrates fats and protein How does the body regulate iron homeostasis o Through regulation iron digestion absorption transport storage and excretion Iron digestion and absorption o Influenced by The individuals iron status The level of dietary iron consumption The type of iron present in the foods consumed The amount of stomach acid present to digest the foods And the presence of dietary factors that can either enhance or inhibit the absorption of iron o Fe 3 stored in ferritin o Fe 3 stored in hemosiderin o Fe 3 bound to transferring for transport o Heme iron part of hemoglobin and myoglobin and is found only in animal based foods such as meat fish and poultry More absorbable plant based and animal based foods o Non heme iron the form of iron that is not part of hemoglobin or myoglobin Found in o Meat factor in meant fish and poultry that enhances the absorption of non heme iron stomach acid vitamin c phytates polyphenols soybean protein fibers vegan diet is approximately 10 compared with the 14 to 18 o transferrin the primary iron transport protein in the blood o receptors on the cell increase and decrease in number depending on the cells need for o The body is capable of storing small amounts of iron in two storage forms ferritin and o Iron storage are in the liver bone marrow and spleen o Ferritin is the normal storage form whereas hemosiderin storage occurs predominately in the diet iron transport iron iron storage hemosiderin in condition of iron overload Regulation of total body iron o Iron absorption o Iron losses o Storage and recycling of iron RDA o Men 19 8 mg day o Women 19 50 18 mg day o Women 51 8 mg day o Pregnant women 27 mg day o UL 45 mg day Food sources o Meats poultry and fish o Breakfast cereals and breads are enriched or fortified with iron Non heme and less absorbable Toxicity o Accidental iron overdose is the most common cause of poisoning deaths in children Supplements o Nausea vomiting diarrhea o Hemochromatosis excessive absorption of dietary iron and altered iron storage Treatment reducing dietary intake of iron avoiding high intakes of vitamin c and blood removal Deficiency o Most common nutrient deficiency in the world o High risk for iron deficiency infants and young children adolescent girls premenopausal women and pregnant women Many factors contribute to iron deficiency o Poor dietary intakes of iron o Blood and sweat o Diets high in fiver or phytates that bind iron o Low stomach acid o Or poor iron absorption due to poor gut health or the consumption of dietary supplements containing high levels of minerals such as calcium that compete with iron absorption binding sites Iron deficiency progresses through three stages o Stage 1 iron depletion Decrease iron stores Reduced ferritin level No physical symptoms o Stage 2 iron deficiency erythropolesis Decreased iron transport Reduced transferrin Reduced production of heme Physical symptoms include reduced work capacity o Stage 3 iron deficiency anemia Decreased production of normal red blood cells Reduced production of heme Inadequate hemoglobin to transport oxygen Symptoms pale kin fatigue reduced work performance impaired immune and cognitive functions Zinc Positively charged trace mineral Enzymatic functions o Estimated that more than 100 different enzymes within the body require zinc for their functioning Structural functions o Synthesize the heme structure in hemoglobin o Maintain the structural integrity and shape of proteins Zinc fingers Regulatory functions o Regulatory of gene expression What factors alter zinc digestion absorption and balance o Increase during times of growth sexual development and pregnancy o High non heme iron intakes can inhibit zinc absorption o The phytates and fiber found in whole grains and beans strongly inhibit zinc absorption o Animal based proteins increasing the absorption of zinc o 19 11 mg day and 8 mg day o UL 40 mg day RDA Food sources Toxicity o Red meats some seafood whole grains and enriched grains and cereals Deficiency o Dietary zinc doesn t lead to toxicity o Supplements intestinal pain and cramps nausea vomiting loss of appetite diarrhea and headaches o Depress immune function and decrease high density lipoprotein concentration o Reduce copper and iron status o Uncommon in the US o Growth retardation in children o Diarrhea delayed sexual maturation and impotence eye and skin lesion hair loss and impaired appetite o Don t have a good way assessment parameters for zinc Copper Trace mineral Functions o Primarily found as a component of ceruloplasmin A protein that is critical for its transport o Cofactor in the metabolic pathways that produce energy Serotonin What factors alter copper absorption and balance o The major site of copper absorption is in the small intestine o Related to the amount of copper in the diet with absorption decreasing on high copper diets and increasing on low copper diets RDA o 19 900micrograms day o UL 10 mg day Food sources o Organ meats seafood nuts and seeds o Whole grain foods Toxicity o Long term effects not studied in humans o Accidental copper toxicity has occurred by drinking beverages that have come into contact with copper o Symptoms abdominal pain and cramps nausea diarrhea and vomiting o Liver damage occurs in the extreme cases o Rare o Anemia reduced levels of white
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