Nutrition in Developing Countries

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Nutrition in Developing Countries
GH 555/NUTR 555 11 April 2008
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Terminology

• Malnutrition impaired development linked to
  both deficient and excessive nutrient intake
• Overnutrition excessive intake leading to
  energy imbalance, overweight and chronic health
  problems
• Hunger physiological state when food not able
  to meet energy needs, leading to loss of lean
  body mass and muscle
• Undernutrition most common form of malnutrition
  in developing countries, although increasing
  prevalence of overnutrition as well double
  burden

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Major Nutritional Problems in the World

• Obesity
• Nutrition-related chronic diseases
• Protein-energy malnutrition
• Micronutrient deficiency problems
• Iron deficiency anemia
• Vitamin A deficiency
• Iodine deficiency disorders
• Zinc deficiency
• Folate deficiency

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Causes of Undernutrition

• Undernutrition has a complex etiology
• Often involves multiple, overlapping deficiencies
  of protein, energy and micronutrients rarely do
  these occur in isolation
• The primary cause of undernutrition is inadequate
  food intake, but is compounded by illness and
  malabsorption
• Insufficient access to food, poor health
  services, the lack of safe water and sanitation,
  inadequate child and maternal care and poverty
  are underlying causes

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Prevention and Management of Undernutrition

• Heightened visibility over past 2-3 years due to
  successful and innovative programs
• Gates Foundation
• Public-private partnerships
• GAIN Ten Year Strategy for Micronutrients
• World Bank Repositioning Nutrition
• Lancet Special Series on Undernutrition

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Global Magnitude of Undernutrition

• Undernutrition is largely preventable cause of
  over 35 - or 3.5 million child deaths
• 11 of the total disease burden worldwide is due
  to maternal and child undernutrition
• 80 of the world's undernourished children live
  in just 20 countries
• Opportunity for intervention is from pregnancy to
  two years of life where the greatest impact may
  be realized

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Importance of Nutrition

• Malnutrition is the single most important risk
  factor for disease
• When poverty is added to the picture, it produces
  a downward spiral that may end in death
• Malnutrition has important consequences for
  cognitive and behavioral development

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Importance of Nutrition

• Because small children become small adults, their
  work capacity is also reduced physically
• Small women have more complications from
  pregnancy they also give birth to smaller
  babies, perpetuating the cycle of poor growth and
  development

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Intergenerational Cycle of Growth Failure
Child growth failure
Low weight and height in adolescents
Early pregnancy
Low birthweight baby
Small adult woman
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Death, Inadequate Growth Development
Conceptual Framework
Inadequate Health Services Unhealthy Environment
Inadequate Education
Political and Ideological Superstructure
Economic Structure
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Causes of Malnutrition

• Malnutrition is a complex condition that involves
  multiple, overlapping deficiencies of protein,
  energy and micronutrients
• A child becomes malnourished because of illness
  in combination with inadequate food intake.
• Insufficient access to food, poor health
  services, the lack of safe water and sanitation,
  and inadequate child and maternal care are
  underlying causes.

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Consequences of Malnutrition

• PEM has important consequences for the survival,
  health and development of young children
• Malnutrition contributes to 56 of all child
  deaths, because of its impact on infectious
  diseases
• This is roughly 8-10 times higher than
  conventional estimates that ignore the
  potentiating effects of malnutrition on disease
  and the effects of mild and moderate malnutrition
  (MMM)

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Consequences of Malnutrition

• The impact of malnutrition on morbidity and
  mortality has important policy implications
• Interventions that combine health care,
  nutritional improvement, and reductions in
  disease exposure will have greatest impact

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Causes of Mortality among Preschool Children, 2002
Other
Perinatal
Deaths associated with malnutrition
56
HIV/AIDS
Acute Respiratory Infection
Measles
Malaria
Diarrhea
Source World Health Organization
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Major Nutritional Problems in the World

• Protein-energy malnutrition
• Obesity
• Micronutrient deficiency problems
• Iron deficiency anemia
• Vitamin A deficiency
• Iodine deficiency disorders
• Zinc deficiency
• Nutrition-related chronic diseases

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Classification of Malnutrition

• Historically, cause of protein-energy
  malnutrition fluctuated
• Protein or energy or ..
• Until past ten years, PEM defined clinically
• Kwashiorkor
• Low weight, stunted linear growth, Apathy
• Edema, Muscle wasting, Changes in skin
  pigmentation
• Marasus
• Severe stunting
• Loss of subcutaneous fat

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Classification of Malnutrition

• WHO recommends three anthropometric indicators
  for assessment of nutritional status
• Wasting (Low weight-for-height)
• Stunting (Low height-for-age)
• Underweight (Low weight-for-age)
• Classification based on SD scores from
  International Growth Reference
• Moderate malnutrition (-2 to -3 SD from reference
  median)
• Severe malnutrition (lt -3 SD from reference
  median)
• Most figures combine moderate severe (lt -2 SD)

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Classification of Malnutrition

• Stunting
• Insufficient height gain relative to age
• Implies long-term under nutrition and poor health
• Wasting
• Insufficient weight gain relative to
  length/height losing weight
• Implies acute or recent under nutrition
• Underweight
• Insufficient weight gain relative to age
• Composite indicator of wasting and stunting
• Most often used parameter for growth monitoring

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Other consequences of malnutrition - Economic
costs

• Malnutrition leads to reduced productivity,
  hampering economic growth and effectiveness of
  investments in health and education, and
  deepening poverty.
• Vitamin and mineral deficiencies are estimated to
  cost some countries the equivalent of more than 5
  per cent of their GNP in lost lives, disability
  and productivity

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Nutrition in developing countries Basic Overview
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Vitamin A Deficiency
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Vitamin A Deficiency

• Contributing factor in 2.2 million deaths each
  year from diarrhea and 1 million deaths from
  measles among preschool children under five
• Severe deficiency can also cause irreversible
  corneal damage, leading to partial or total
  blindness

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Global Distribution of Vitamin A Deficiency
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Under-5-mortality distribution of countries with
vitamin A survey information
Schultink, 2002
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Functions

• Vision (night, day, colour)
• Epithelial cell integrity against infections
• Immune response
• Haemopoiesis
• Skeletal growth
• Fertility (male and female)
• Embryogenesis

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Malnutrition and child death
VAD ?
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Association between xerophthalmia and mortality
Sommer, Hussaini, Tarwotjo, 1983
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Impact of vitamin A supplementation on child
mortality
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Impact of vitamin A on measles mortality
Sommer, West, 1996
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Maternal HIV-1 infection andvitamin A status
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Vitamin A status and some major childhood
infections

• benefit is greatest on measles
• fewer attendances in clinics
• fewer admissions to hospital
• little effect on respiratory infections
• Shigella gut infection reduced
• malaria reduced
• reduced mortality in children with HIV

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Impact of supplementation on mortality related to
pregnancy up to 12 weeks post partum
West, Katz, Khatry et al, 1999
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Stages of deficiency
Increasing deficiency

• Subclinical
• reducing stores
• lowering serum level
• metaplasia
• Clinical
• xerophthalmia
• - non-blinding
• - blinding

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Tests for assessment of vitamin A status
Decreasing status

• Subclinical
• relative dose-response test
• serum retinol
• retinal rod function
• conjunctival impression cytology (CIC)
• Clinical
• night blindness
• conjunctival and corneal eye signs

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Conjunctival xerosis (X1A) and corneal xerosis
(X2)
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Bitots spot (X1B)
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Conjunctival and corneal xerosis (X1A and X2)
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Keratomalacia (X3A, X3B)
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Keratomalacia
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Why do children become vitamin A deficient?

• Mothers of poor children often have VAD and
  produce deficient breast milk
• Childrens diets provide too little vitamin A
• Children spend a large part of their
  childhoodbeing sick
• Provitamin A carotenoids in vegetables and
  fruitsare less readily bioavailable than
  previously thought
• Early weaning is often onto foods low in vitamin
  A
• Growth velocity, and therefore vitamin
  Arequirement, is higher during pre-school age
  than atany other time postnatally

7 April 2006
Humphrey, Katz et al, 2002
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Major food sources

• Dark green leafy vegetables
• Yellow fruits
• Carrots
• Palm oils
• Liver and liver oils

NUTR 600 EPID 600 8 April 2005
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Examples of common vegetable/fruit-carotenoid
sources
mg RE/100 g edible portion Red palm
oil 30000 Buriti palm (pulp)
3000 Carrots 2000 Dark green leafy
vegetables 685 Sweet potato, red and yellow
670 Mango golden 307 Apricot
250 Papaya 124 Tomato 100
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Examples of common animal vitamin A sources
mg retinol/100 g edible portion Fatty fish
liver oils Halibut 900,000 Shark 180,0
00 Cod 18,000 Herring and
mackerel 50 Dairy
produce Margarine - fortified
900 Butter 830 Cheese, fatty type
320 Eggs
140 Milk 40 Meats Liver of sheep
and ox 15,000 Beef, mutton, pork
0-4
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Food supply of vitamin A - from provitamin A
carotenoids and preformed vitamin A food sources
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Control of VADD

• Supplementation
• Fortification
• Diet diversification
• Infectious disease control
• Disaster relief
• Plant breeding

7 April 2006
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A child receiving a vitamin A capsule
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Coverage of vitamin A supplementation in children
6-59 months old, Nicaragua
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Prevalence of VADD (serum retinol lt 20mg/dl) in
children 6 - 59 months old, Nicaragua
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Prevention 2 Food fortification
Scientific rationale Economic
viability Industrial capacity Community
acceptance Training Sustainability
Advocacy Monitoring Legislative support
Quality control

• Economic viability
• Community acceptance
• Sustainability
• Monitoring
• Quality control

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Prevention 3 Dietary diversification
Advantages Ultimate solution Community
involvement Generating income Provides other
nutrients Components Production (home,
school) Consumption (by vulnerable
groups) Problems Long-term cooperation Difficult
in slums and desert areas
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Promotion of training and education
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Recent insights into dietary control of VADD in
developing countries

• Mean daily provitamin A intake is only 470 mg
  RE/day and not 720 as earlier calculated
• Provitamin A activity 40 lower than previously
  stated
• Solely vegetarian diet probably not protective
• Recent research explains why VADD have persisted
  despite abundant provitamin A food supplies
• Biofortification and fortification seen as most
  viable and sustainable strategies

West, McLaren, 2002