Beef, Minerals, BVitamins and Brains

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Beef, Minerals, B-Vitamins and Brains
Explore the Power of Protein
Nebraska, Kansas and Missouri Beef Councils
Kansas City
May 28, 2008
Guy H. Johnson, Ph.D.
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Optimal cognitive performance and development is
an innate desire of all parents
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Fifteen healthy male students (mean age 26
years)
Protein (14)
11 Mix
CHO (41)
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Beef is source of nutrients needed for cognition
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Iron
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Iron requirements are high during childhood

• Iron requirements (IOM 2001)
• Young infants 0.27 mg/day (AI)
• 7 12 months 11 mg/day
• 1 3 year 7 mg/day
• 4 8 year 10 mg/day
• The DV for iron for food labeling is 18 mg

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Iron deficiency is prevalent

• Iron deficiency affects more than 3.5 billion
  people in developing world and is also prevalent
  in industrialized world
  
• Prevalence of anemia among preschoolers
• 17 preschoolers in industrialized countries
• 53 in developing world
• 700,000 US toddlers (1-2 year age) are iron
  deficient and 240,000 have frank anemia (Looker
  et.al., 1997)
  
• Iron deficiency is most prevalent hematological
  disorder in childhood (Dallman et.al., 1984)

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MMWR 2002, 51(40)897-899
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and the problem is increasing
Estimates of world-wide iron deficiency by public
health organizations
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Beef contributes to iron status in several ways

• One 3 oz serving of Beef provides
• 14 DV of iron
• 36 RDA for 1-3 year old children
• 25 RDA for 4-8 year old children

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Beef contributes to iron status in several ways

• One 3 oz serving of Beef provides
• 14 DV of iron
• 36 RDA for 1-3 year old children
• 25 RDA for 4-8 year old children
• Beef has heme iron which is more bioavailable
  than non-heme iron (Hallberg 2002)
  

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Beef contributes to iron status in several ways

• One 3 oz serving of Beef provides
• 14 DV of iron
• 36 RDA for 1-3 year old children
• 25 RDA for 4-8 year old children
• Beef has heme iron which is more bioavailable
  than non-heme iron (Hallberg 2002)
  
• Beef protein increases non-heme iron absorption
  compared to soy protein

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Beef contributes to iron status in several ways

• One 3 oz serving of Beef provides
• 14 DV of iron
• 36 RDA for 1-3 year old children
• 25 RDA for 4-8 year old children
• Beef has heme iron which is more bioavailable
  than non-heme iron (Hallberg 2002)
  
• Beef protein increases non-heme iron absorption
  compared to soy protein
  
• Beef diet was better than chicken diet in
  maintaining plasma ferritin in 87 adolescents

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Beef as supplemental dietary source of
iron for infants

• American Academy of Pediatrics 2003
• Foods other than human milk or infant formula
  may be introduced to healthy infants at 4-6
  months of age
  
• Ziegler Fomon (Nutrition Reviews 199654348)
• From an iron perspective, meat is an attractive
  food choice. Meat not only provides heme iron
  that is well absorbed, it also enhances the
  absorption of dietary nonheme iron
• Krebs et. al. (J Ped. Gastroenterol. Nutr.
  200642207)
  
• Straind beef was well tolerated as the first
  supplemental food among exclusively breast fed
  infants
  
• Similar serum ferritin concentrations at nine
  months among infants fed iron-fortified cereals
  or strained beef

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Iron and cognition
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Roles of iron in the brain

• Brain obtains iron via transferrin receptors
• Cerebrospinal fluid is reported to have high
  levels of iron and transferrin
  
• Iron is required for proper myelination of spinal
  cord and white matter
  
• Iron is a co-factor for a number of enzymes
  involved in neurotransmitter synthesis
  
• Iron is also involved in neurotransmitter
  functioning

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Observational Studies
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There was an association between hookworm
infection and mental development in school
children
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Source Adapted from Grantham-McGregor Ani, J
Nutr, 2001131649S
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Iron status and cognitive functioning
in young women
Baseline values of cognitive performance among
18-35 year old women according to iron status
Anemic
Deficient
Replete
Source Murray-Kolb et al. Am J Clin Nutr
200785778-787

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Adequate iron is essential for optimum mental
development and cognitive function

• Pollitt et.al., 1997
• Iron deficiency anemia (IDA) is a risk factor for
  poor educational performance in schoolchildren
  
• deAndraca et.al., 1997
• Research has shown an association between iron
  deficiency anemia and adverse effects on behavior
  and psychomotor development in infants and
  children
• Sandstead 2000
• Neuropsychologic impairment is one of several
  potential outcomes of iron and zinc deficiencies
  

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Adequate iron is essential for optimum mental
development and cognitive function

• Viteri and Gonzalez 2002
• The adverse effects of micronutrient deficiencies
  include poor mental and neuromotor performance
  
• Bryan et.al., 2004
• Under nutrition and deficiencies of iodine, iron,
  and folate are all important for the development
  of the brain and the emergent cognitive functions

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The punch line

• Iron is a critical nutrient for optimum cognitive
  development in infants and young children and
  beef is a good source of highly bioavailable iron

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Clinical Trials in Pre- and School-Aged Children
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Iron supplementation and cognitive performance
in pre- and school-aged children
Source Adapted from Grantham-McGregor Ani, J
Nutr, 2001131649S
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Most supplementation studies in this age
range are positive
Eleven studies on pre- or school age children and
cognitive development

• Eight studies provide positive evidence
• Three studies failed to demonstrate a positive
  response
  
• Deinard et.al., 1986 used wide range of subjects
• Pollitt et.al., 1989 reported improvement in Hb
  status in placebo group
  
• Soweando et.al., 1989 may have used test that was
  not sensitive to discriminate changes.
  

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The punch line

• Reasonably Consistent Evidence
• Iron supplementation may improve cognitive
  performance in pre-school and school-aged
  children who are anemic or iron deficient.

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Clinical Trials in Pre- and School-Aged Children
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Iron supplementation and cognitive performance
in pre- and school-aged children
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Most supplementation studies in this age
range are negative
Ten controlled intervention studies on infants
two years or less on cognitive development

• Seven studies failed to improve cognitive
  development
  
• Three positive studies demonstrated a positive
  response
  
• Driva et al, 1985 used a non dietary
  intervention
  
• Walter et al, 1989 used a non-randomized design
  and small number of subjects
  
• Idjradinata Pollitt 1993 used a relatively long
  intervention period of 4 months
  

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The punch line

• Prevention of iron deficiency anemia among older
  infants and very young children (less than 2
  years of age) with iron-containing foods like
  beef is very important because correction of this
  condition does not consistently resolve cognitive
  impairment.

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Iron Cognition Summary

• Iron is a critical nutrient for optimum cognitive
  development in infants and young children
  
• Beef is a good source of highly bioavailable
  iron
  
• Iron supplementation may improve cognitive
  performance in pre-school and school-aged
  children who are anemic or iron deficient
  
• Prevention of iron deficiency anemia among older
  infants and very young children (less than 2
  years of age) with iron containing foods like
  beef is very important because correction of this
  condition does not consistently resolve cognitive
  impairment

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Zinc
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Zinc requirements are high during childhood

• Zinc requirements (IOM 2001)
• Young infants 2 mg/day (AI)
• 7 12 months 3 mg/day (RDA)
• 1 3 year 3 mg/day (RDA)
• 4 8 year 5 mg/day (RDA)
• 9 13 years 8 mg/day (RDA)
• 14 18 years girls 9 mg/day (RDA)
• 14 18 years boys 11 mg/day (RDA)
• The DV for zinc for food labeling is 15 mg

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Zinc deficiency is prevalent

• 12 of US population failed to meet the Estimated
  Average Requirement of zinc established by IOM
  
• Less than 3 children failed to meet EAR of zinc
• Risk of low dietary intake of absorbable zinc and
  consequent zinc deficiency are widespread
  problems affecting between 33 to 50 of the
  worlds population
• Zinc deficiency is likely to be widespread in
  low-income countries
  
• Zinc deficiency ranged from 0.9 in US to 95.4
  in South Asia

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Beef contributes to zinc status in several ways

• One 3 oz serving of Beef provides
• 39 DV of zinc
• 119 RDA for 1-3 year old children
• 117 RDA for 4-8 year old children

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Beef contributes to zinc status in several ways

• One 3 oz serving of Beef provides
• 39 DV of iron
• 119 RDA for 1-3 year old children
• 117 RDA for 4-8 year old children
• The bioavailability of zinc from beef is
  excellent
  

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Beef contributes to zinc status in several ways

• One 3 oz serving of Beef provides
• 39 DV of iron
• 119 RDA for 1-3 year old children
• 117 RDA for 4-8 year old children
• The bioavailability of Zinc from beef is
  excellent
  
• Beef protein increases absorption of zinc from
  other dietary sources (Etcheverry et.al., 2006)

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Beef as supplemental dietary source of
zinc for infants

• American Academy of Pediatrics 2003
• Foods other than human milk or infant formula
  may be introduced to healthy infants at 4-6
  months of age
  
• Krebs et. al. (J Ped. Gastroenterol. Nutr.
  200642207)
  
• Straind beef was well tolerated as the first
  supplemental food among exclusively breast fed
  infants
  
• Similar serum ferritin concentrations at nine
  months among infants fed iron-fortified cereals
  or strained beef

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Zinc and cognition
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Roles of zinc in the brain

• Zinc is critical nutrient for brain development
• Zinc serves various structural and functional
  roles in mature brain
  
• Zinc-dependent enzymes are involved in brain
  growth
  
• Zinc-finger proteins participate in brain
  structure and neurotransmission
  
• Zinc-dependent neurotransmitters are involved in
  brain memory function
  
• Zinc is involved in the precursor production of
  neurotransmitters
  
• Metallothionein-III is one protein that binds
  zinc in neurons

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Observational Studies
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Results of observational studies are mixed

• Thatcher et.al., 1984
• 5 16 year old 184 Maryland public schools
  students
  
• Reading ability was positively associated with
  hair zinc concentration
  
• Cavan et.al., 1993
• 162 low income school children (mean age 6.8
  years) in Guatemala
  
• No difference in cognitive performance between
  subjects with hair zinc concentrations above or
  below 1.68 µmol/g
  
• Wachs et.al., 1995
• 110 Egyptian pre-adolescent (7-10 years old)
• Zinc intake assessed by dietary recall
• Zinc intake was not associated with cognitive
  performance

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Clinical Trials
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Zn supplementation and cognition performance
randomized controlled studies
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Summary Zinc and cognition

• Cross-sectional studies
• One study found positive association between hair
  zinc concentration and cognitive performance
  
• Two studies failed to detect significant
  association
  
• Cross-sectional studies have several limitations
  and have much less weight that Randomized
  controlled trials
  
• Randomized Controlled trials
• 5 studies reported positive effects of zinc
  supplementation alone or in combination on
  cognitive performance
  
• 3 studies reported lack of positive association
• Two of these have been criticized for using
  limited measures
  

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The punch line

• Zinc supplementation may improve cognitive
  performance in pre-school and school-aged
  children who have poor zinc status but more data
  are needed

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Meat and cognition
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Children
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Cognitive Performance in Elderly
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Maintaining cognitive function is a huge issue

• As many as 5.2 million people in the United
  States are living with Alzheimers.
  
• 10 million baby boomers will develop Alzheimer's
  in their lifetime.
  
• Every 71 seconds, someone develops Alzheimers.
  
  
• Alzheimer's is the seventh-leading cause of
  death.
  
• The direct and indirect costs of Alzheimer's and
  other dementias to Medicare, Medicaid and
  businesses amount to more than 148 billion each
  year.

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Cross-sectional studies show a positive
association between B-vitamins and cognition

• Goodwin (1983) 260 elderly 60
• Bell (1990) 102 elderly mean 74.5
• Ortega (1996) 177 elderly Spanish
• Riggs (1996) 70 men 54-81
• Wahin (1996) 250 elderly (75-96)
• Hassing (1999) 71 elderly (90-101)
• Lindeman (2000) 883 elderly 65
• Jelicic (2001) 698 men mean 68.7
• Duthie (2002) Abdereen elderly 81
• Stewart (2002) 248 elderly 55-75
• Miller (2003) -- 1789 elderly 60 or older
• Ravaglia (2003) 650 elderly 65 or older
• Ramsos (2005) 1789 elderly 60 or older

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so do the prospective studies

• La Rue (1997) 137 elderly (66-90)
• Teunissen (2003) 144 healthy men and women
  (30-80)
  
• Elias (2005) 2096 elderly 60 or older
• Tucker (2005) 231 elderly 67 years

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but the intervention studies are mixed

• Folic acid supplementation
• Fiorvavnti (1997) 30 elderly (70-90)
• Bryan (2002) 202 healthy subjects (20-91)
• Stott (2005) 185 65 or older
• Pathansali (2005) 24 elderly 75
• Wolters (2005) 75-96
• Vitamin B6 supplementation
• Tolonen (1988) 44 elderly (66-96)
• Dror (1996) 12 elderly (65-85)
• Bryan (2002) 202 healthy subjects (20-91)

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Dementia in Elderly
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Beef nutrients and dementia
case control studies

• B-vitamin status associated with clinical
  dementia
  
• McCaddon et.al., 1998
• Miller et.al., 2002
• Quadri et.al., 2004, 2005
• Campbell et.al., 2005
• B-vitamin status not associated with clinical
  dementia
  
• Mizrahi et.al., 2004
• Ariogul et.al., 2005

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Beef nutrients and dementia
prospective cohort studies

• B-vitamin status associated with clinical
  dementia
  
• Seshadri et.al., 2002
• Kado et.al., 2005
• Ravaglia et.al., 2005
• B-vitamin status not associated with clinical
  dementia
  
• Snowdon et.al., 2000
• Luchsinger et.al., 2004

There are no controlled intervention studies on
the effect of beef on the development of dementia
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Meat eating and dementia observational
studies

• Giem et.al., 1993
• No significant difference in the incidence of
  dementia among vegetarian, lacto-ovo and meat
  eaters. No significant association between meat
  eating and dementia in a second study
• Many confounding variables were not adjusted.
• Ross et.al., 1999
• Preference of Western diet (including meat) was
  protective of dementia in 25 years follow-up
  study on Japanese Population in Hawaii
  
• Barber-Gateau et.al., 2002
• Fish or seafood intake (not the meat intake) was
  associated with lower risk of dementia among
  French in this two year study

Some evidence to suggest a link between meat
eating and lower risk of dementia
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Meat Intake Homocysteine Levels observational
studies

• Meat eaters had lower serum homocysteine
  concentrations than vegetarians
  
• Mann et.al., 1999
• Herrmann et.al., 2001
• Gao et.al., 2003
• Koebnick et.al., 2004
• Serum HCY was not negatively associated with meat
  intake
  
• Osahug et.al., 1998
• Diakoumopoulou et.al., 2005

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Meat Intake Homocysteine Levels
intervention study

• Haulrik et.al., 2002
• Low protein or high protein diet for six months
• 25 decrease in serum homocysteine in high
  protein group

Red meat intake is lowers serum homocysteine
There is consensus that elevated levels of
homocysteine are associated with diminished
cognitive functions
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Summary and conclusions

• Beef is a good or excellent source of B-vitamins
  that are known to lower homocysteine
  
• Meat intake is associated with lower homocysteine
  levels
  
• Low blood homocysteine concentrations may help
  reduce the risk of Alzheimer
  
• Adequate intake of meat and B-vitamins found in
  beef may help maintain cognitive performance in
  elderly persons

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Overall Conclusions

• Beef is an important source of macro- and
  micronutrients important for cognitive
  development/function
  
• Iron Zinc are critical nutrients for cognitive
  development in infants and young children
  
• Protein-rich foods may stimulate short-term
  cognitive performance
  
• Beef and/or beef nutrients may be important for
  maintenance of cognitive function in elderly

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Thank you!!
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