Chapter 12: Nutrients Involved in Blood Health and ImmunityWhat 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 cellso Transport oxygen- Leukocytes: white blood cellso The key to our immune function and protect us from infection and illness- Platelets: cell fragmentso Assist in the formation of blood cloths and help stop bleeding- Plasma: fluid portion of bloodo Need to maintain adequate blood volume so that blood can flow easily throughout the bodyA Profile of Nutrients That Maintain Healthy Blood- Iron, zinc, copper, vitamin k, folate, and vitamin b 12Iron- Trace mineral- The most common nutrient deficiency in the world- Ferrous iron (fe +2) to ferric iron (fe+3)- Functionso Hemoglobin: the oxygen-carrying protein found in the erythrocyteso 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 bodyo 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 absorptiono 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 irono Fe 3+ stored in ferritino Fe 3+ stored in hemosiderino Fe 3+ bound to transferring for transporto Heme iron: part of hemoglobin and myoglobin and is found only in animal-based foods such as meat, fish, and poultry. More absorbableo Non-heme iron: the form of iron that is not part of hemoglobin or myoglobin. Found in plant-based and animal-based foods.o Meat factor: in meant, fish, and poultry that enhances the absorption of non-heme iron in the diet stomach acid vitamin c phytates polyphenols soybean, protein, fibers vegan diet is approximately 10% compared with the 14% to 18%- iron transporto transferrin, the primary iron-transport protein in the bloodo receptors on the cell increase and decrease in number depending on the cells’ need for iron- iron storageo The body is capable of storing small amounts of iron in two storage forms: ferritin and hemosiderin. o Iron storage are in the liver, bone marrow, and spleeno Ferritin is the normal storage form, whereas hemosiderin storage occurs predominately in condition of iron overload- Regulation of total body irono Iron absorptiono Iron losseso Storage and recycling of iron- RDA o Men 19< 8 mg/dayo Women 19-50 18 mg/dayo Women 51< 8 mg/dayo Pregnant women 27 mg/dayo UL 45 mg/day- Food sourceso Meats, poultry, and fisho Breakfast cereals and breads are enriched or fortified with iron Non-heme and less absorbable- Toxicityo Accidental iron overdose is the most common cause of poisoning deaths in children Supplementso Nausea, vomiting, diarrheao 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- Deficiencyo Most common nutrient deficiency in the worldo High risk for iron deficiency: infants and young children, adolescent girls, premenopausal women, and pregnant women- Many factors contribute to iron deficiencyo Poor dietary intakes of irono Blood and sweato Diets high in fiver or phytates that bind irono Low stomach acido 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 stageso Stage 1: iron depletion Decrease iron stores Reduced ferritin level No physical symptomso Stage 2: iron-deficiency erythropolesis Decreased iron transport Reduced transferrin Reduced production of heme Physical symptoms include reduced work capacityo 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 functionsZinc- Positively charged trace mineral- Enzymatic functionso Estimated that more than 100 different enzymes within the body require zinc for their functioningo Synthesize the heme structure in hemoglobin- Structural functionso Maintain the structural integrity and shape of proteins Zinc fingers- Regulatory functionso Regulatory of gene expression- What factors alter zinc digestion, absorption, and balance?o Increase during times of growth, sexual development, and pregnancyo High non-heme iron intakes can inhibit zinc absorption o The phytates and fiber found in whole grains and beans strongly inhibit zinc absorptiono Animal based proteins increasing the absorption of zinc- RDAo 19< 11 mg/day and 8 mg/dayo UL 40 mg/day- Food sourceso Red meats, some seafood, whole grains, and enriched grains and cereals- Toxicityo Dietary zinc doesn’t lead to toxicityo Supplements: intestinal pain and cramps, nausea, vomiting, loss of appetite, diarrhea, and headacheso Depress immune function and decrease high-density lipoprotein concentrationo Reduce copper and iron status - Deficiencyo Uncommon in the USo Growth retardation in childreno Diarrhea, delayed sexual maturation and impotence, eye and skin lesion, hair loss, and impaired appetiteo Don’t have a good way assessment parameters for zincCopper- Trace mineral- Functionso Primarily found as a component of ceruloplasmin A protein that is critical for its transporto 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 intestineo Related to the amount of copper in the diet, with absorption decreasing on high-copper diets and increasing on low-copper diets- RDAo 19< 900micrograms/dayo UL 10 mg/day- Food sourceso Organ meats, seafood, nuts, and seedso Whole grain foods- Toxicityo Long-term effects not studied in humanso Accidental copper toxicity has occurred by drinking beverages that have come into
View Full Document
Unlocking...