NDFS 200 Final Exam- Trace Minerals

What are food sources, absorption path, functions, deficiency, and toxicity of iron?

• FOOD SOURCES:

  • heme iron

    • animals

  • nonheme iron

    • plants

• ABSORPTION:

  • active transport into enterocytes

  • high iron: goes into ferritin as a mucosal block

    • will get excreted with enterocyte

  • low iron: will get transported out of enterocyte by ferroportin

  • oxidized to ferric (Fe3+) by copper

  • outside of enterocyte Fe 2+ → Fe 3+

  • binds to transferrin (only binds to ferric)

  • endocytosis brings transferrin and receptor into cells

• FUNCTIONS:

  • oxygen transport

  • redox reactions

  • iron-containing enzymes

  • immune system

• DEFICIENCY:

  • low work/exercise capacity

  • low immune function

  • high anemia

  • lots of fatigue

  • low growth and development in children

• TOXICITY:

  • leading cause of poisoning in children (chewable vitamins)

  • hematochromatosis

    • muscosal block is ineffective

What are food sources, absorption path, functions, deficiency, and toxicity of zinc?

• FOOD SOURCES:

  • meat

  • seafood

  • nuts

  • grains

  • beans

• ABSORPTION:

  • active transport

  • metallothienin is mucosal block in enterocytes

  • transported via albumin in bllod

  • no storage, will be excreted in feces via gallbladder

• FUNCTIONS:

  • 300 enzymes

    • DNA synthesis

    • heme synthesis

    • bone formation

    • taste acuity

    • immune function

    • reproduction

    • growth and development

  • gene transcription

    • zinc fingers (help proteins bind to DNA)

• DEFICIENCY:

  • dermatitis

  • loss of appetite

  • delayed growth and sexual maturation

  • impaired vitamin A function

• TOXICITY:

  • too much can reduce copper absorption

What are food sources, absorption path, functions, deficiency, and toxicity of copper?

• FOOD SOURCES:

  • liver

  • shellfish

  • nuts

  • soy

  • lentils

  • dark chocolate

• ABSORPTION:

  • active transport and diffusion

  • binds to metallothienin

  • transported by albumin

• FUNCTIONS:

  • redox Cu2+ (cupric) to Cu+ (cuprous)

  • metabolism, ETC

  • iron absorption

  • superoxide dismutase

    • lower oxidative damage

  • lysyl oxidase

• DEFICIENCY:

  • may increase risk for ALS

• TOXICITY:

  • not common

    • wilson’s disease (cannot excrete copper)

What are food sources, absorption path, functions, deficiency, and toxicity of manganese?

• FOOD SOURCES:

  • grains

  • tea

• ABSORPTION:

  • active transport and passive diffusion

  • transported using albumin, transferrin, and alpha-2-macrogobulin

• FUNCTIONS:

  • antioxidant

  • carbohydrate metabolism

  • gluconeogenesis

  • collagen formation

What are food sources, absorption path, functions, deficiency, and toxicity of iodine?

• FOOD SOURCES:

  • depends on soil content

  • lima beans

  • walnuts

  • iodized salt

• ABSORPTION:

  • iodide and iodate absorbed in small intestine

  • transported to thyroid via sodium dependent channels

• FUNCTIONS:

  • part of thyroid hormone

  • 3 musketeers are active

  • thyroxine (T4) becomes triiodothyronine (T3) with help of selenium

• DEFICIENCY:

  • goiters

  • low t4 → more TSH to grow thyroid

• TOXICITY:

  • goiter/cretinism during pregnancy

What are food sources, absorption path, functions, deficiency, and toxicity of selenium?

• FOOD SOURCES:

  • seafood

  • meats

  • cereals

  • grains

• ABSORPTION:

  • absorbed at selenomethionine and selnocysteine

  • no affected by selenium stores

• FUNCTIONS:

  • 25 selonoproteins

    • glutathione peroxidase (spares vitamin E)

    • thyroid hormone metabolism (T4 → T3)

    • immune function

• DEFICIENCY:

  • increase risk for prostate cancer

  • cause keshan disease

What are food sources, absorption path, functions, deficiency, and toxicity of chromium?

• FUNCTIONS:

  • enhance insulin secretion

  • promote glucose uptake

• DEFICIENCY:

  • rare, parenteral solutions

  • weight loss, glucose intolerance, nerve damage

• TOXICITY:

  • no UL set

What are food sources, absorption path, functions, deficiency, and toxicity of fluoride?

• FOOD SOURCES:

  • fluoridated water

  • tea

  • seafood

  • seaweed

• ABSORPTION:

  • passive diffusion

  • 80-90% absorbed

• FUNCTIONS:

  • forms hydroxylfluorapatite

  • remineralization of teeth

• DEFICIENCY:

  • dental caries?

• TOXICITY:

  • dental fluorosis

How would you describe the development of cancer and the effect of genetic, environmental, and dietary risk factors on the development of cancer?

what will increase risk:

• obesity

• meat

• fried foods

• alcohol

what will decrease risk (not therapeutic):

• fruits and vegetables

• vitamin D

• calcium