Chapter 12 Flashcards
Define trace elements and provide common examples
Minerals required in amounts <100 mg/day
ex. iron, zinc, copper, manganese, selenium, iodine, fluoride, and chromium.
What are the functions of iron in the body?
essential for oxygen transport (hemoglobin and myoglobin), energy production, and immune function.
Heme Iron?
Found in animal products, better absorbed.
Non-heme iron?
Found in plant products and less efficiently absorbed.
What factors affect increase of iron absorption?
Vitamin C, heme iron, and low iron stores.
What are the forms of iron in the body?
Storage: Ferritin and hemosiderin.
Transport: Transferrin.
What factors affect decrease of iron absorption?
Phytates, calcium, polyphenols (tea, coffee), and high iron stores.
Define iron deficiency anemia and list symptoms and susceptible groups.
A condition caused by insufficient hemoglobin production, leading to oxygen delivery issues.
Symptoms: Fatigue, weakness, pale skin.
Susceptible groups: Infants, children, adolescent girls, pregnant women, and athletes.
What are the risks of iron toxicity?
Excess iron can damage organs (e.g., liver, heart), cause gastrointestinal distress, and lead to hemochromatosis.
Who is at risk for zinc deficiency, and what are the symptoms?
At risk: Vegetarians, pregnant women, elderly, and those with genetic conditions.
Symptoms: Poor growth, delayed wound healing, skin rashes, and reduced immune function.
What are the functions of zinc and factors affecting its absorption?
Functions: Enzyme activity, immune regulation, DNA synthesis, and cell membrane stability.
Absorption: Enhanced by animal sources; inhibited by phytates.
What are the dietary sources and functions of copper?
Sources: Organ meats, seafood, nuts, seeds, and whole grains.
Functions: Assists in iron metabolism, connective tissue synthesis, and antioxidant protection.
What is the role of manganese in the body?
Essential for antioxidant enzyme superoxide dismutase, and is involved in metabolism, cartilage formation, and urea synthesis.
What is selenium’s role in the body, and how does it interact with vitamin E?
Functions: Antioxidant (glutathione peroxidase), thyroid hormone production.
Role in cancer: May protect against cancer in selenium-deficient individuals.
Interaction with vitamin E: Reduces vitamin E requirement.
How does iodine relate to thyroid hormones, and what are deficiency effects?
Function: Essential for thyroid hormone synthesis.
Deficiency: Causes goiter, cretinism, and developmental delays.
What are chromium’s functions and food sources?
Functions: Enhances insulin action and regulates blood glucose.
Sources: Brewer’s yeast, liver, nuts, and whole grains.
How does fluoride prevent dental caries, and what are the risks of toxicity?
Role: Strengthens enamel, reduces acid production, and promotes remineralization.
Toxicity: Can cause mottled teeth, kidney damage, and bone abnormalities.
What nutrients are involved in antioxidant activity?
Vitamins: C, E.
Minerals: Selenium, zinc, copper, manganese.
Which nutrients support immune function?
Vitamins A, D, B6, B12, folate; zinc; selenium; copper; iron; omega-3 fatty acids
Vitamin A
Controls gene expression related to immune cell development.
Maintains mucosal barriers to prevent infections.
Vitamin D
Modulates immune response, reducing inflammation.
Enhances pathogen-fighting ability of macrophages and supports T-cell activation.
Vitamin B6
Necessary for the production of lymphocytes (white blood cells).
Supports antibody formation.
Vitamin B12 and Folate
Involved in DNA synthesis for the rapid production of immune cells.
Vitamin C
Protects immune cells as an antioxidant.
Enhances skin barrier function and supports white blood cell function.
