Trace Minerals

Question 1

Name the trace minerals

Answer 1

Iron, Zinc, Copper, Manganese, Iodine, and Selenium

Question 2

Describe characteristics of trace minerals. Why are they called trace? What generally causes toxic levels? What influences trace minerals in foods? Who is impacted by deficiency?

Answer 2

• Needed in very small quantities in the human body, but they perform essential functions important to health
• Usually toxicity is caused by the use of supplements
• Deficiencies affect all ages, but in children they can affect growth

Question 3

Identify function, recommendations, deficiency and symptoms, toxicity and symptoms, and who is at risk, and rich food sources of Zinc

Answer 3

Functions: promote cell production and tissue growth and repair, a part of many enzymes
Recommendations: Males 11mg/day & Females 8mg/day
Deficiency: not common; growth retardation, appetite loss, delayed wound healing (sores around the mouth)
Toxicity: loss of appetite, impaired immunity, low HDL, copper and iron deficiency
People at risk for toxicity: people who take Zinc supplements
Food Sources: protein foods, whole grains and legumes, crab, milk, cheese, meat, poultry; of Animal Origin is best source

Question 4

Identify function, recommendations, deficiency and symptoms, toxicity and symptoms, and who is at risk, and rich food sources of Iron

Answer 4

Functions: oxygen transport, essential for hemoglobin production and therefore transportation of oxygen
Recommendations: Males 8mg/day & Females 18mg/day; Pregnant 27mg/day; UL 45mg/day
Deficiency: Anemia- presents itself as a loss of energy and shortness of breath
Toxicity: Hemochromatosis with symptoms such as fatigue, headache, irritability and lowered work performance

Question 5

What is hemoglobin and what is its relationship to iron?

Answer 5

Most of our body’s iron is found in hemoglobin and myoglobin. Hemoglobin is our body’s Red Blood Cells, and iron helps transport oxygen in hemoglobin

Question 6

What is myoglobin and what is its relationship to iron?

Answer 6

Most of our body’s iron is found in myoglobin and hemoglobin. Myoglobin is a heme protein found in muscle cells

Question 7

Describe iron absorption in the body. What is the sequence of absorption? What is ferritin? What is the role of transferrin? In general, how much dietary iron is absorbed? What does the body do to adapt to its iron needs? Where is surplus iron stored?

Answer 7

• The portion of the small intestine called the duodenum is the chief area where iron absorption takes place. There may be a second minor absorption site near the end of the small intestinal tract. Once iron is absorbed it is carried (transported) by a protein called transferrin.
• Ferritin is an iron storage protein, when iron is stored in the body, this is what it attaches to
  Transferrin is the iron transport protein, found in blood and is important for crossing the cell membrane
  –Transferrin’s role is to transport iron through the blood to the liver, spleen, and bone marrow. Very important process because too much or too less is bad.
  -The most significant influence on iron absorption is the amount of iron already stored in your body. The body stores iron in various places, including the liver. If your stores are high, your body absorbs less iron from the foods you eat. Conversely, low iron stores increase your ability to absorb iron.
  -Mucosal cells in the intestine store excess iron in mucosal ferritin

Question 8

Differentiate between heme and nonheme iron sources in food. . What are food sources of each? How much (%) of a typical diet is comprised of each? How does the absorption rate (%) differ between the two?

Answer 8

Heme- derived from animal flesh, about 10% of the daily average iron intake, is well absorbed (25% absorbed)
Nonheme- derived from plants, about 90% of the daily average iron intake, is less well absorbed (17% absorbed)

Question 9

Identify factors that enhance and inhibit absorption.

Answer 9

Heme: ??????????
Nonheme:
- Inhibit: Phytates, Oxalates, Calcium and Phosphorus in milk, Tannic Acids in coffee and tea
- Enhance: Vitamin C, MFP factor

Question 10

Describe iron recycling.

Answer 10

• Transferrin carries iron in the blood
• Some iron delivered to myoglobin of muscle cells
• Bone marrow incorporates hemoglobin of red blood cells and stores excess iron in ferritin
• Iron-containing hemoglobin in red blood cells carries oxygen
• Some losses of bleeding may occur
• Liver (and spleen) dismantles red blood cells, packages iron into transferrin, and stores excess iron in ferritin
• Some losses via sweat, skin, and urine
• Back to the beginning

Question 11

Define anemia. What are three major causes of anemia? What three nutrients are associated with anemia? What physiological states contribute to these types of anemia?

Answer 11

• A condition marked by a deficiency of red blood cells or of hemoglobin in the blood
• Blood loss, Lack of red blood cell production, High rates of red blood cell destruction
• ?????????