Nutrition ch 10 Trace Minerals
Recommended intake for zinc
11 mg for men 19+ and 8 mg for women 19+; body cannot store zinc so need it through intake daily; recommend vegetarians consume 2X as much zinc as nonvegetarians
zinc deficiency
20% of world is at risk for this (highest risk in South Asia and parts of Africa & Central America); uncommon in US except 12% of pple are at risk including alcoholics (alcohol reduces zinc absorption and incr. zinc excretion), vegetarians (legumes and whole grains - a staple of vegetarians - inhibit absorption), and the elderly (reduced food intake and impaired absorption)
what % of the world is at risk for iodine deficiency? what about pregnant women?
40% of the world is at risk; 55% of US pregnant women have iodine blood concentrations in the mild iodine deficiency range
UL for selenium
400 micrograms in adults; single high dose may be fatal - thought toxicity normally occurs over time with high levels of intake through supplementation; symptoms are hair and nail loss and brittleness and garlic breath
RDA for selenium
55 micrograms for adults; dietary selenium is pretty well absorbed and (unique to this mineral) is not regulated in relation to nutritional status
RDA for copper
900 micrograms per day in adults; approx 55-75% of dietary copper is absorbed (which is more efficient than other trace minerals)
Adequate Intake (AI) level for flouride & UL for flouride
AI: 4 mg for men 19+ and 3 mg for women 19+; UL: 10 mg for men and women 19+
Which are the ultratrace minerals?
Boron, Nickel, Silicon, Vanadium
Infographic 10.12 pg 324
Infographic 10.12 pg 324
All of the following are general properties of trace minerals:
Many are cofactors for enzymes; very little digestion is required; they are absorbed primarily in small intestine; they circulate freely in the blood
iron deficiency anemia facts
Most common form of anemia - affects 30% of world and 10% of women aged 20-49; usually caused by an extreme inadequate intake of iron; AKA microcytic hypochromic anemia; this is when oxygen carrying capacity of RBC is inadequate; children and infants get this more than adults
RDA and UL for iodine
RDA for men & women 19+ years old is 150 ug and UL is 1100 ug
Iron intake recommendations
RDA for men 19+ y/o is 8mg, for women 19-50 is 18 mg (assuming bioavailability of 18%, where vegans and vegetarians have bioav. of 10%, and athletes have 30% bioavail. bc of incr. iron losses); UL for men & women 19+ y/o is 45mg
Molybendum
a cofactor for only 4 enzymes; average intake of the US population is well above the RDA; deficiencies are unknown and toxicity is low
Cretinism
a condition characterized by arrested mental and physical development, deafness & muteness, stunted growth, and delayed sexual maturation; can be caused by severe iodine deprivation during fetal growth
Iron Deficiency Anemia
a condition characterized by fatigue, decreased immune function, and impaired development due to reduced levels of iron-containing hemoglobin in RBC and subsequent decrease in O2 transport around the body
thyroid gland
a gland located in the neck that releases the iodine-containing thyroid hormones involved in regulating metabolism and protein synthesis
Thyroid Stimulating Hormone (TSH)
a hormone released from the anterior pituitary that stimulates the thyroid gland to produce and secrete thyroid hormones
Chromium
a popular dietary supplement but biological benefits are not supported by studies; deficiency is only observed in hospitalized patients who have been receiving 100% of nutrients intravenously for extended period of time; THERE IS QUESTION AS TO WHETHER THIS IS AN ESSENTIAL NUTRIENT
Hemoglobin
a protein in RBC that contains iron and carries O2 to tissues; made up of 4 units - each unit contains one heme group and one protein group; sometimes referred to as "oxygen transport protein"
Myoglobin
a protein that functions to provide O2 to muscles; contains less iron than hemoglobin
what happens if a pregnant woman doesn't get sufficient iodine during her pregnancy?
can cause fetal brain development problems and results in lower IQs and intellectual disabilities
iron deficiency anemia causes
causes include blood loss (most common), inadequate resources for eating heme iron (common in vegetarians), poor iron absorption (common in elderly or with pple with disease)
which trace mineral has been demonstrated to play a role in slowing the progression of age-related macular degeneration, which can lead to loss of vision?
copper
function of iron
energy metabolism, antioxidant actions, the immune response, DNA synthesis (which involves reproduction, growth and healing)
how can the bioavailability (the extent to which a mineral can be absorbed and utilized in the body) be influenced
form of the food, our nutrition status, our age, pregnancy
function of selenium
function wasn't established until 1970s; is a cofactor for several antioxidant enzymes and in the activation of thyroid hormone, making it essential for normal growth, development, and metabolism
function of copper
functions as cofactor in oxygen dependent enzymes (only about 12 copper containing enzymes though), helps form hemoglobin and collagen, energy metabolism, formation of connective tissue, regulation of iron storage/transport, antioxidant functions; slows muscular degeneration
Iron Absorption
in healthy individuals about 10-15% of dietary iron is absorbed; but it can adjust based on what's necessary for the body
functions of manganese
involved in antioxidant functions, metabolism of carbs/cholesterol/amino acids, important for synthesis of proteins needed for bone growth and maintenance and wound healing
What is the version of iodine that's in the body?
iodide
Which trace mineral is an essential component of thyroid hormone
iodine
Of the trace minerals, only _____ cannot be excreted in the urine or bile
iron
most abundant trace mineral in the body
iron
What's the number one nutritional disorder in the world, affecting developing and industrialized nations?
iron deficiency
Heme iron
iron derived from hemoglobin; the most bioavailable form of dietary iron found in meat, fish, and poultry; most iron in our body occurs as this
Nonheme iron
iron derived from plant foods such as lentils and beans but also present in significant quantities in meat and fish; less bioavailable than Heme iron; assists in the functioning of enzymes
According to the WHO, the #1 nutritional disorder worldwide is
iron-deficiency anemia
dental flourosis
is when excessive intake of fluoride occurs; characterized initially by small opaque flecks on the teeth and by stains or pits in the teeth with long term exposure; bones can get this with lifelong over exposure making them too dense and more likely to facture
In contrast to heme iron, nonheme iron
makes up the majority of iron we consume
UL for zinc
men and women 19+ is 40mg
Symptoms of zinc deficiency
mild to moderate deficiency: impaired immune function, appetite/weight loss, delayed sexual maturation, slowed growth; severe deficiency: hair loss, diarrhea, infertility in men, impaired neurological and behavioral functions
The majority of iodine intake in the US comes from
milk and processed grains
where does the majority of the iodine intake come from?
milk and processed grains (about 70%) -> only 15% comes from salt
trace minerals
minerals essential in nutrition, needed in small quantities daily; These are iodine, iron, zinc, copper, selenium, molybdenum, chromium (this one is questionable), and manganese; minerals with a daily requirement of less than 100 mg; AKA microminerals; fluoride is a trace mineral but not required to sustain life so not an essential nutrient; all the trace minerals in your body fit in the palm of your hand
Ultratrace minerals
minerals that are found in the boyd but are not considered essential at this time bc only need less than 1 microgram/day; these include Arsenic, Boron, Nickel, Silicon, and Vanadium; no specific biological or physiological functions; Daily Intake recommendations are not determinable (ND) bc of lack of data; food is considered only safe source of these nutrients
iron deficiency facts
most prevalent nutritional disorder in the world and only nutrient deficiency to affect a signif % of women and children in the industrialized countries; affects kids' permanent cognitive impairment
Cofactor
nonprotein organic or inorganic substances that assist enzymes in carrying out chemical reactions
who is especially affected by inadequate intakes of trace minerals?
pregnant women and children in rapid growth stages
function of flouride
prevention of dental cavities (dental caries) through hardening and maintenance of tooth enamel; stabilizes structure of bone; NOT considered an ESSENTIAL NUTRIENT bc not required for reproduction or growth or to sustain life;
selenium deficiency
rarely causes obvious symptoms/illness; more common to occur with deficiency of other antioxidant nutrients, physiological stresses, viral infections, and chemical exposure
what do the thyroid hormones do?
regulate energy metabolism and protein synthesis, and play critical roles in the development of the fetal skeleton and brain; when there is not enough iodine, the thyroid cannot produce enough thyroid hormones and it slows metabolic rate
what is fortified to add iodine
salt; 86% of world has access to this salt
symptoms for excessive intake of zinc
short term effects = nausea, vomiting, abdominal cramps, and diarrhea; long term effects = copper deficiency, altered iron function, lowered levels of HDL
flouridation of water
started in 1940s to help prevent dental caries; 74% of population is served by community water systems that receive flouridated water; ENVIRONMENTAL PROTECTION AGENCY (EPA) is responsible for safeguarding our public drinking water
iron absorption: heme vs nonheme
the absorption of heme iron is little affected by other nutrients, nonheme can be enhanced or inhibited by other substances in foods (enhanced when eating Vitamin C and meat, fish, and poultry - MFP; inhibited by soy protein, phytates, and polyphenols); calcium reduced absorption of both; Iron cannot be excreted into the urine so absorption is important
where does iodine content depend on?
the environment it comes from which varies from region to region; the sea has highest concentrations of iodine in foods (animal and plant products); it depends on where the veggies and fruits are grown which will determine how much iodine is in the plants
Trace minerals differ from major minerals in all of the following ways:
their daily requirement is less than 100 mg; their safe range of intake is narrower; they are found in smaller amounts in the body; they include iodine and iron
How does trace mineral toxicity normally happen?
through supplements; it's hard to overdose in trace minerals from foods alone
iron deficiency anemia symptoms
tired, out of breath, poor performance, slow cognitive and social development, trouble with body temp, more susceptible to infections, preterm birth, low birth weight, increasing infant heatlh problems later
symptoms of too much iron and symptoms of iron deficiency anemia
too much iron: constipation, nausea, diarrhea, vomiting, dizziness, shock, rapid heartbeat (common death of children; more common in men than women; more common in pple with hemochromatosis); too little iron: apathy, fatigue, liver damage, immune problems
manganese toxicity and deficiency
toxicity is more common than deficiency even though only 5% is absorbed (worst of all the trace minerals)
copper deficiency
uncommon when alone, but more common when secondary to other factors: post gastric bypass surgery, conditions that cause nutrient malabsorption, excessive zinc intake; deficiency often results in anemia; symptoms include impaired immune response and osteoporosis
Goider
visible thyroid gland enlargement; iodine deficiency
Which trace mineral is required for the function of perhaps more proteins in the body than any other mineral?
zinc
what is required for the functioning of perhaps more proteins in the body than any other mineral?
zinc; research indicates that zinc binds to about 10% of all proteins in the body including more than 900 enzymes; it is required for virtually every essential process in the body: regulation of protein synthesis, reproduction, cell division, growth and development, immune response, and neurological functions
