Trace Minerals Flashcards
Identify the trace minerals
iron zinc selenium copper manganese fluoride chromium molybdenum
_________ requires iron for activation
Hydroxylase
________ ______ requires selenium for activation
Glutathione peroxidase
_____ is a nutrient of great concern in terms of global and national health.
iron
In poor or developing countries of the world, as many as __% to __% of young children and pregnant women have compromised health due to iron deficiency or iron-deficiency anemia.
30%-50%
Even in the United States where food is plentiful, ___ deficiency is a health concern for toddlers, adolescent girls, and women in their childbearing years, especially those of low socioeconomic status.
iron
Iron has two common ionic states, ________ and ________.
- Fe++ (ferrous iron, reduced)
2. Fe+++ (ferric iron, oxidized)
Iron is involved in many _________ _______ _______, including the electron transport chain in the final production of ATP in the mitochondria.
oxidation- reduction reactions
Since iron has an affinity for oxygen (O2), iron-rich __________ picks up O2 in the lungs and transports it via red blood cells to all parts of the body.
hemoglobin
________ in muscle is another Fe-containing protein that binds O2
myoglobin
iron is important in brain and nervous tissue function since it is a _______ necessary for the catalytic activity of enzymes responsible for the synthesis of several neurotransmitters.
cofactor
Iron embedded in a _____ structure (from hemoglobin and myoglobin) is found only in foods of animal origin and has _____ bioavailability.
- heme
2. high
________ iron (as Fe++ or Fe+++) is found both in foods of animal origin and in foods of plant origin and has a lower bioavailability.
nonheme
Heme iron has higher bioavailability with ___% being absorbed. However, for a vegetarian who eats no animal foods, only about __% of iron is absorbed. Overall in the mixed American diet, about ___% of iron is absorbed.
- 25%
- 10%
- 18%
The iron recommendation for vegetarians is ___ times the RDA to compensate for the significantly lower bioavailability of nonheme iron as the only source of dietary iron.
1.8
___% of iron is absorbed during the high growth years of childhood.
35%
An ____ peptide factor found in meat, fish, and poultry enhances nonheme iron absorption.
MFP
_________ in a meal enhances nonheme iron absorption by keeping the form of iron in the reduced state.
vitamin C
Plant foods high in _______ and ______ such as in legumes, whole grains, and rice can reduce nonheme iron absorption in a meal by ________ it causing increased excretion in the stool rather than absorption into the body
- phytates and fibers
2. binding
Iron is always bound to specific proteins in tissues and fluids of the body. ____ _______ proteins play critical roles in iron homeostasis.
iron binding
Inside the lumen of the small intestine, iron from food is found in the forms of _____ or _____ iron.
heme or nonheme
After iron is transported into the small intestinal cell, either as heme or nonheme iron, it is sequestered by a protein call ______.
ferritin
_______ has the capacity to temporarily store thousands of iron atoms. It is also the storage protein for iron in the liver.
ferritin
If the body is in need of iron, then _____ in intestinal cells releases iron, which then attaches to _______.
- ferritin
2. ferroportin
________ is a transport protein and it is associated with the membrane on the blood side of the intestinal cell (also called a mucosal cell).
ferroportin
Iron does not travel free in the blood. It is attached to the protein called blood _______, which delivers iron to the body tissues.
transferrin
When the body has gotten enough iron, the liver secretes the hormone, ______. It blocks _______ from transferring iron into the blood.
- Hepcidin
2. ferroportin
IRON EXCRETION
_______ cells die at a high rate and are then shed into the intestinal lumen resulting in iron from ferritin being excreted in feces.
Mucosal
TRUE OR FALSE
Extremely little iron can be excreted in urine since it is protein bound and proteins are not filtered out by the kidney.
TRUE
TRUE OR FALSE
Women lose iron monthly via menstruation; thus, men and postmenopausal women are at higher risk for toxicity compared to premenopausal women.
TRUE
Iron deficiency anemia is a ______ ______ anemia (small cell, low color) that results from not only depleted iron stores, but also depleted ____ transport and reduced production of________.
- microcytic hypochromic
- iron
- hemoglobin
Iron deficiency refers to depleted iron stores in the ______, but not severe enough to cause anemia.
liver
Iron deficiency may cause _______ and _______ changes often mistaken for laziness; symptoms may include fatigue, decreased ability to concentration, and sluggish reactivity.
behavioral and motivational
In the U.S., some behavior and cognitive problems in children have been attributed to lower iron status. Researchers hypothesize that iron’s role in the synthesis of _________ is the cause of these symptoms.
neurotransmitters
Hereditary iron overload or _________ is the most common genetic disorder in the United States, affecting some 1.5 million people.
hemochromatosis
Hemochromatosis can cause _____ ____, ____, ____, and ______.
liver damage
apathy
lethargy
fatigue
Adult men require __ mg/day of iron, whereas premenopausal women require more than twice that amount, __ mg/day,
8 mg/day
18 mg/day
The UL for iron is set at __ mg/day in a supplement.
45mg/day
More enzymes require ____ compared to any other class of metalloenzymes.
zinc
Zinc regulates
- immune function
- thyroid function
- motor and cognitive development in children
- vitamin A metabolism
- taste
- wound healing
Severe zinc deficiency is characterized by _______ ______ and _______ sexual maturity in children and adolescents.
- growth retardation
2. delayed
Plant-based diets high in fiber and phytates can cause the ______. of zinc in the intestine.
binding
TRUE OR FALSE
In the US diet, red meat, whole grains, some fortified cereals, and milk are the richest sources of zinc.
TRUE
Less than __% of dietary zinc is absorbed into blood.
40%
This intestinal storage protein for zinc is called __________.
metallothionein
Only when the body needs zinc will ________ release zinc for transport into blood. Zinc is transported in blood attached to a blood protein called ________, however, blood _______ can also transport zinc.
- metallothionein
- albumin
- transferrin
Unabsorbed zinc from either diet or pancreatic secretions is excreted in ____.
feces
Zinc, iron, and copper have similar chemical characteristics, thus they can interact and _______ in the body.
compete
The UL for Zinc is ___mg/day
40 mg/day
High iron absorption either from overload disorder or iron supplements can over saturate blood ________, leaving little room for the transport of _____ and resulting in reduced absorption of _____.
- transferrin
- zinc
- zinc
Chronic use of zinc supplements can cause decreased absorption of _____ or _____, due to competition with transport.
iron and copper
Iodide is part of the structure of the thyroid hormone, _______, which controls basal metabolic rate, body temperature, growth, reproduction, muscle function, and energy metabolism.
thyroxine
An iodine deficiency leads to a decreased production of active _____. In an effort to make more, the body increases ______ stimulating hormone, causing cells of the thyroid gland to enlarge in an attempt to trap more iodide.
- thyroxine
2. thyroid
Thyroid gland enlargement results in a very visible growth on the neck known as a ______ ______.
simple goiter
During pregnancy, a thyroid deficiency will cause severe mental and physical retardation of the developing fetus, a condition known as ______.
cretinism
TRUE OR FALSE
Inadequate dietary iodine is still a major public health issue in developing nations where fortification programs are absent.
TRUE
Iodine is abundant in ______ and is present in the soil near the _____.
- seafood
2. ocean
Iodized _____, introduced in the 1930’s, eliminated iodine deficiency.
salt
Fluoride has an important role in the strengthening of ______ and _____.
bones and teeth
Fluoride replaces the hydroxyl group in hydroxyapatite (the crystalline structure in bones and teeth) and forms an even stronger compound.
fluorapatite
Fluoride naturally occurs in many soils and water supplies, but in areas with low fluoride, __________ of the public water supply (at 1 ppm) has dramatically lowered the incidence of decayed and missing teeth.
flouridation
0.1 ppm level of fluoride in drinking water can lead to…
increased incidence of dental caries and missing teeth
1 ppm level of fluoride in drinking water can lead to…
optimal dental health
8 ppm level of fluoride in drinking water can lead to…
increased incidence of fluorosis
Selenium is present in the enzyme, glutathione peroxidase, where, along with vitamin E and other antioxidants, it blocks the formation of _____ ______.
free radicals
TRUE OR FALSE
Seafood, meat, whole grains, fruits, and vegetables are all good sources of selenium in the U.S. diet.
TRUE
Copper is found in enzymes that affect ________ formation, act as an ______, and are involved in _______ ________.
- hemoglobin
- antioxidant
- energy metabolism
______ is part of the enzyme, superoxide dismutase.
Copper
superoxide dismutase, like glutathione peroxidase, is very important in reducing ______ _______ formation.
free radical
Chromium is notable for its role in ______ and _____ metabolism.
carbohydrate and lipid
________ helps maintain glucose levels by enhancing insulin activity.
Chromium
Chromium deficiency is characterized by ______-like symptoms.
diabetes
TRUE OR FALSE
Chromium is abundant in unrefined foods, meats, cheese, and grains
TRUE
