Mineral Nutrition: Copper, Iodine, Zinc, Manganese
sites for assessing micronutrient contents of food
www.nal.usda.gov/fnic/foodcomp/search/
www.nutritiondata.com
final exam will be wednesday week 12
research assignment due, post to discussion group
four more minerals to talk about
COPPER
not quite so busy a cofactor
several redox rxns
mitochondrial cytochrome requires it (mitochondrial c oxidase)
CT and bone formation
iron transport: activates transport system, puts iron in correct oxidation state
animals who are copper deficient have skeletal problems
antioxidant functions
superoxide dismutase (SOD) has many versions, one with Cu
ceruloplasmin may be pro or anti-oxidant, copper containing blood protein
(I thought this prot was for copper transport???)
check Cu for IDA? yes but uncommon etio for IDA
too much zinc-->copper deficiency, then consider it as etio for any iron def anemia
iron can compete with copper, impair absorption
multis, zinc and iron supplements should contain copper if taken longterm
COPPER DEFICIENCY
uncommon
microcytic anemia is early sign
anemia<--iron def<--transport problem<--low copper
suboptimal intake may increase osteoporosis risk
RDA vs average diet
900 mcg vs 1.2 mg/day men
900 mcg vs 1.1 mg/day
SOURCES
water supply copper lumbing
foods: mushrooms, nuts, legumes
supplements: inorganic: Cu oxide, sulfate
organic: gluconate, amino acid chelate (these are easier to absorb)
SAFETY
too much rare, usudt environmental contamination
UL of 10mg/day based on amounts known to be safe for liver
CLINICAL
Wilson's dz increases risk of chronic toxicity even at low intake
liver toxicity and brain degeneration, dementia
usu presents with liver disease, elevated transaminases
he says it's txed with a drug, two other profs have said zinc is the main tx
may benefit blood lipids
may increase oxidative stress
p27 research summary
OSTEOPOROSIS & COPPER
3mgday for 2 years readuced lumbar spine bone loss in perimenopausal women
shorter study in younger adults found no benefit
adding copper and other trace minerals improved the bone benefits of Ca++ supplement
CHROMIUM
(2nd handout)
use it a lot for insulin resistance, blood sugar probs
Cr+3 is a nutrient
Cr+6 is a toxin, never found in food, is in industrial chemicals
enhances insulin function
mechanism unclear
may bind intracellular molecule that increases insulin receptor activity
high simple sugar intake increases chromium excretion
this may be imp link btw diet and impaired insulin function
deficiency causes impaired glucose tolerance and increased insulin requirements
in animals and humans
hard to measure chromium levels in people and in food
brewers yeast contains chromium
measuring devices have chromium alloys in them: lack of sensitive and accurate testing
new equipment made of ceramics
AI = adequate intake looks low to Gerber: 30-35 mcg male, 20-25 for female
based on levels in normal diets, not on optimal function
clinical dosages are many times higher
food content variable, testing poor, no good idea what the best food sources are
supplements: inorganic chloride is poorly absorbed, studies using this mb off
organic: nicotinate, picolinate, chromium yeast
SAFETY: no UL dt lack of toxicity evidence
isolated reports of kidney and liver damage poss from large doese of Cr picolinate, no proof
high doses were used
more is not always better
IGT = impaired glucose tolerance (fasting plasma glucose 100-125)
pictured: lynae brand chromium picolinate 200 mcg
dosing 200 mcg improved blood sugar control and lipids in most studies
effects on blood lipids in healthy subjects is inconsistent (cholesterol)
type 2 DM studies: inconsistent results using less than 200mcg/day
1000mcg/day Cr picolinate: 2/3 recent studies found significant benefits
adding 2mg/day biotin may help
weight loss and body building claims have largely been disproved
It's all about blood sugar (have on shelf in medicinary)
IODINE
limited number of functions
It's all about thyroid
component of T3 and T4
essential for many regulatory processes
circulating iodine is trapped by the thyroid gland under the control of TSH from the pituitary
pituitary??? monitors circulating T4
cells of thyroid may degenerate, be attacked by autoimmune process
IODINE DEFICIENCY
most common cause of preventable brain damage mainly in developing countries (cretinism)
in adults: goiter, hypothyroidism, minor mental impairment
can be devastating to child if mom is hypo during pregnancy
IODINE INTERACTIONS
selenium: required by deiodinase enzymes that convert T4 to active T3
selenium supp worsens hypothyroidism in iodine-def pts who didn't get iodine too
GOITROGENS
iodine or thyroid antagonists
some found in cruciferous vegetables, soy
not clinically important unless large amounts consumed with marginal iodine intake
RDA
been the same for nearly 30 years, not too controversial
150 mcg male and female
average diet 240+ mcg/day male, 190 female
intake has decreased since early 1970's but still OK
avoiding iodized salt, seafood and seaweed may increase risk of def
SOURCES
iodized salt
seafood, some sea vegetables
animal products depending on feed content
crop foods depending on soil content
(Peabody yesterday said iodized salt is toxic)
SUPPLEMENTS
potassium iodide
kelp powder
not in all multivits
IODINE SAFETY
UL is 1100 mcg/day
large amounts can elevate TSH in iodine sufficient individuals
can cause hyperthyroidism in iodine deficient individuals with autonomous thyroid nodules
too much can also depress the thyroid
DON'T TREAT HYPOTHYROID PTS WITH IODINE UNTIL A DEFICIENCE IS ESTABLISHED
he doesn't say how to test for iodine, but rather that we should test for antibodies
pharmacologic doses: one dose 50-100mg to reduce thyroid cancer risk from radiation exposure
***5 mg/day for fibrocystic breast condition!!! long term
liquid form treated his wife's fibrocystic breasts, "seems to work"
he doesn't know about long term effect of low dose on thyroid
MANGANESE
absorption is low and decreased by plant chems and high intake of other minerals
abundant in plant based foods but phytates block it
is natural amount enough? is there hidden deficiency?
antioxidant function: another form of superoxide dismutase (mitochondrial form)
several metabolic enzymes
CT and bone: collage syn, glycoaminoglycan synthesis
manganese is included in bone and joint formulas
iron taken for anemia may impair manganese status
calcium and magnesium have mild effects on manganese bioavailability (hmmm)
use multi with manganese
DEFICIENCY not documented
preliminary research suggests possible effects on glucose tolerance and bone development
AI: 2.3 mg male, 1.8 mg female
based on average diets, healthier diets have lots more
supplementation may raise SOD activity, SOD presence measured increase with mineral supp
SOURCES: whole grains (82% lost in refining),
nuts, leafy greens, tea (tanins may lower bioavailability)
SUPPS: Mn sulfate, popular ingredient in CT formulas
Gerber still prefers organic base, sulfates can irritate GI
ascorbate, aa chelate, etc
SAFETY: occupational and environmental Mn toxicity
-->neuro probs in miners, industry workers
unclear if high dose supps are risky
11mg UL led to reformulation of several manganese containing products
he's not sure how they picked 11mg
OSTEOPOROSIS
women with ost have lower Mn blood levels than healthy women
one trial added 5mg Mn, 2.5 mg Cu, and 15 mg Zn to a Ca++ formula
3 groups: placebo, Ca++ only, and Ca++ plus minerals
perimenopausal women
supp w/ minerals prevented spinal bone loss better than calcium alone
no research separating out Manganese
no research on arthritis or trauma healing
www.nal.usda.gov/fnic/foodcomp/search/
www.nutritiondata.com
final exam will be wednesday week 12
research assignment due, post to discussion group
four more minerals to talk about
COPPER
not quite so busy a cofactor
several redox rxns
mitochondrial cytochrome requires it (mitochondrial c oxidase)
CT and bone formation
iron transport: activates transport system, puts iron in correct oxidation state
animals who are copper deficient have skeletal problems
antioxidant functions
superoxide dismutase (SOD) has many versions, one with Cu
ceruloplasmin may be pro or anti-oxidant, copper containing blood protein
(I thought this prot was for copper transport???)
check Cu for IDA? yes but uncommon etio for IDA
too much zinc-->copper deficiency, then consider it as etio for any iron def anemia
iron can compete with copper, impair absorption
multis, zinc and iron supplements should contain copper if taken longterm
COPPER DEFICIENCY
uncommon
microcytic anemia is early sign
anemia<--iron def<--transport problem<--low copper
suboptimal intake may increase osteoporosis risk
RDA vs average diet
900 mcg vs 1.2 mg/day men
900 mcg vs 1.1 mg/day
SOURCES
water supply copper lumbing
foods: mushrooms, nuts, legumes
supplements: inorganic: Cu oxide, sulfate
organic: gluconate, amino acid chelate (these are easier to absorb)
SAFETY
too much rare, usudt environmental contamination
UL of 10mg/day based on amounts known to be safe for liver
CLINICAL
Wilson's dz increases risk of chronic toxicity even at low intake
liver toxicity and brain degeneration, dementia
usu presents with liver disease, elevated transaminases
he says it's txed with a drug, two other profs have said zinc is the main tx
may benefit blood lipids
may increase oxidative stress
p27 research summary
OSTEOPOROSIS & COPPER
3mgday for 2 years readuced lumbar spine bone loss in perimenopausal women
shorter study in younger adults found no benefit
adding copper and other trace minerals improved the bone benefits of Ca++ supplement
CHROMIUM
(2nd handout)
use it a lot for insulin resistance, blood sugar probs
Cr+3 is a nutrient
Cr+6 is a toxin, never found in food, is in industrial chemicals
enhances insulin function
mechanism unclear
may bind intracellular molecule that increases insulin receptor activity
high simple sugar intake increases chromium excretion
this may be imp link btw diet and impaired insulin function
deficiency causes impaired glucose tolerance and increased insulin requirements
in animals and humans
hard to measure chromium levels in people and in food
brewers yeast contains chromium
measuring devices have chromium alloys in them: lack of sensitive and accurate testing
new equipment made of ceramics
AI = adequate intake looks low to Gerber: 30-35 mcg male, 20-25 for female
based on levels in normal diets, not on optimal function
clinical dosages are many times higher
food content variable, testing poor, no good idea what the best food sources are
supplements: inorganic chloride is poorly absorbed, studies using this mb off
organic: nicotinate, picolinate, chromium yeast
SAFETY: no UL dt lack of toxicity evidence
isolated reports of kidney and liver damage poss from large doese of Cr picolinate, no proof
high doses were used
more is not always better
IGT = impaired glucose tolerance (fasting plasma glucose 100-125)
pictured: lynae brand chromium picolinate 200 mcg
dosing 200 mcg improved blood sugar control and lipids in most studies
effects on blood lipids in healthy subjects is inconsistent (cholesterol)
type 2 DM studies: inconsistent results using less than 200mcg/day
1000mcg/day Cr picolinate: 2/3 recent studies found significant benefits
adding 2mg/day biotin may help
weight loss and body building claims have largely been disproved
It's all about blood sugar (have on shelf in medicinary)
IODINE
limited number of functions
It's all about thyroid
component of T3 and T4
essential for many regulatory processes
circulating iodine is trapped by the thyroid gland under the control of TSH from the pituitary
pituitary??? monitors circulating T4
cells of thyroid may degenerate, be attacked by autoimmune process
IODINE DEFICIENCY
most common cause of preventable brain damage mainly in developing countries (cretinism)
in adults: goiter, hypothyroidism, minor mental impairment
can be devastating to child if mom is hypo during pregnancy
IODINE INTERACTIONS
selenium: required by deiodinase enzymes that convert T4 to active T3
selenium supp worsens hypothyroidism in iodine-def pts who didn't get iodine too
GOITROGENS
iodine or thyroid antagonists
some found in cruciferous vegetables, soy
not clinically important unless large amounts consumed with marginal iodine intake
RDA
been the same for nearly 30 years, not too controversial
150 mcg male and female
average diet 240+ mcg/day male, 190 female
intake has decreased since early 1970's but still OK
avoiding iodized salt, seafood and seaweed may increase risk of def
SOURCES
iodized salt
seafood, some sea vegetables
animal products depending on feed content
crop foods depending on soil content
(Peabody yesterday said iodized salt is toxic)
SUPPLEMENTS
potassium iodide
kelp powder
not in all multivits
IODINE SAFETY
UL is 1100 mcg/day
large amounts can elevate TSH in iodine sufficient individuals
can cause hyperthyroidism in iodine deficient individuals with autonomous thyroid nodules
too much can also depress the thyroid
DON'T TREAT HYPOTHYROID PTS WITH IODINE UNTIL A DEFICIENCE IS ESTABLISHED
he doesn't say how to test for iodine, but rather that we should test for antibodies
pharmacologic doses: one dose 50-100mg to reduce thyroid cancer risk from radiation exposure
***5 mg/day for fibrocystic breast condition!!! long term
liquid form treated his wife's fibrocystic breasts, "seems to work"
he doesn't know about long term effect of low dose on thyroid
MANGANESE
absorption is low and decreased by plant chems and high intake of other minerals
abundant in plant based foods but phytates block it
is natural amount enough? is there hidden deficiency?
antioxidant function: another form of superoxide dismutase (mitochondrial form)
several metabolic enzymes
CT and bone: collage syn, glycoaminoglycan synthesis
manganese is included in bone and joint formulas
iron taken for anemia may impair manganese status
calcium and magnesium have mild effects on manganese bioavailability (hmmm)
use multi with manganese
DEFICIENCY not documented
preliminary research suggests possible effects on glucose tolerance and bone development
AI: 2.3 mg male, 1.8 mg female
based on average diets, healthier diets have lots more
supplementation may raise SOD activity, SOD presence measured increase with mineral supp
SOURCES: whole grains (82% lost in refining),
nuts, leafy greens, tea (tanins may lower bioavailability)
SUPPS: Mn sulfate, popular ingredient in CT formulas
Gerber still prefers organic base, sulfates can irritate GI
ascorbate, aa chelate, etc
SAFETY: occupational and environmental Mn toxicity
-->neuro probs in miners, industry workers
unclear if high dose supps are risky
11mg UL led to reformulation of several manganese containing products
he's not sure how they picked 11mg
OSTEOPOROSIS
women with ost have lower Mn blood levels than healthy women
one trial added 5mg Mn, 2.5 mg Cu, and 15 mg Zn to a Ca++ formula
3 groups: placebo, Ca++ only, and Ca++ plus minerals
perimenopausal women
supp w/ minerals prevented spinal bone loss better than calcium alone
no research separating out Manganese
no research on arthritis or trauma healing