Malnutrition, definition, causes, indicators for ...

1 malnutrition , definition, causes, indicatorsfor assessmentfroma Public Nutrition perspectiveMaster Human Development and Food Security, Roma III University, May 2016 Marie Claude DopNutripass Nutrition research unit, Institut de Recherche pour le D veloppement, Montpellier, objectives Understand the concept of malnutrition and linkages to food security and human development Realize the magnitude of the problem of malnutrition at global level Know the principal causes of malnutrition in resource-poor contextscontexts Identify vulnerable groups Understand the key indicators for assessing under and overnutrition Know the most important population-based preventive strategies for fighting malnutrition and the indicators that are useful for monitoring their impact Be able to read critically reports on assessment of malnutritionOutlineof the course Introduction Part I: anthropometric indicators Part II: indicators of micronutrient deficiencies Part III: the nutrition transition and the Part III.

2 The nutrition transition and the obesity epidemic Part IV: Nutrition-sensitive interventions and programmesIntroductionWhy does nutrition matter ? Why include nutrition in a Master curriculum on Human Development and Food Security ? What is the relationship between food security and nutrition ?security and nutrition ? Why does nutrition matter to human development ? Where does nutrition feature in Sustainable Development Goals ?Why does nutrition matter ? Is food insecurity related to nutrition ? Nutrition is in the definition of food insecurity Good nutrition is the basis of good health and human well-being Therefore it is central to human development Poor nutrition affects populations health, intellectual and physical capacities; it is a cause of poverty ; it is often transmitted from one generation to the nextNutrition and the SDGsSDG2: End hunger, achieve food security and improved nutrition and promote sustainable agricultureDefinitionsNutrition is the provision of adequate energy and nutrients (in terms of amount and mix and timeliness) to the cells to enable them to perform their physiological function (of growth, reproduction, defense, repair, etc).

3 Growth, reproduction, defense, repair, etc). malnutrition is the result of a lack or an excess in the provision of energy and/or nutrients to the body (undernutritionor overweight/obesity)Definitions (cont d) Nutritional status is the state of the body in relation to nutrition: Clinical, apparent signs of poor nutrition Growth and development of the body: dimensions (anthropometric measures) such as Growth and development of the body: dimensions (anthropometric measures) such as weight and height Composition of the body and biochemical parameters Dietary intake is separate from nutritional statusIssues with terminology malnutrition refers to poor nutritional status Undernourishment* is an FAO concept : it is the number or proportion of persons whose energy consumption is less than their minimum energy needsneeds Malnourished can refer to the state of malnutrition or to inadequate food intakes Hunger is defined as a feeling of discomfort or weakness caused by lack of food, coupled with the desire to eat * Also designated as chronic hunger Types of malnutrition Undernutrition: Protein-energy malnutrition Micronutrient deficiencies Overnutrition: Overweight and obesity Overweight and obesity Health consequences (diabetes, cardiovascular diseases) Co-existence of under and overnutrition.

4 Double burden of malnutrition Obesity and PEM in the same family Obesity and micronutrient deficiencies in the same individual Chronic and acute malnutritionNote that this illustration does not include Childhood overweight/obesitywhich are also forms of malnutritionExamples of stunted children13 Children of the same ageUnderstanding child malnutrition Wasting means that the infant/child is thin: she/he has lost fat and muscle mass Stunting means that the infant/child is short in stature: she/he did not grow in length/height stature: she/he did not grow in length/height has he/she should have Underweight means that she/he weighs less than she/he should A child can be both wasted and stuntedUnderstanding child malnutrition Wasting is usually due to a recent lack of food or illness (infections) that prevents the child from eating or absorbing nutrients of foods Stunting is a long term process, often starting in uterowhich is due to the mother s malnutrition , to food intake lacking quality (insufficient intake uterowhich is due to the mother s malnutrition , to food intake lacking quality (insufficient intake of essential micronutrients))

5 And the repetition of episodes of common infections Overweight and obesity are due to excessive energy intake and lack of physical activityNote that overweight and obesity can co-exist with micronutrient deficiency and with stuntingWasted child (source TALC)Obese boysUNICEF conceptual model of causes of malnutrition & mortalityIntermediatecausesImmediatecaus esHousehold foodinsecurityInadequate caringfor mothers and Inadequate environment Insufficient food intakesIllnessMalnutrition and mortalitycausesUnderlyingcausesinsecurit yfor mothers and young childrenenvironment and health systemGovernmental and non-governmental institutionsPolitical and ideological structureEconomic contextPotential resourcesComments on the UNICEF conceptual model The model is useful for understanding and distinguishing the causes of malnutrition .

6 It distinguishes the short and long routes for fighting malnutrition The model doesn t take into consideration The model doesn t take into consideration overweight/obesity as a form of malnutrition or the double burden of malnutrition It is focused on child malnutrition while malnutrition can affect all ages, but the concept can be applied to other age groupsImpact of undernutritionon child mortality* Undernutrition is rarely a direct cause of death. It is most often an underlying cause of death from common illnesses of which it increases the occurrence and severity: Undernutrition is rarely a direct cause of death. It is most often an underlying cause of death from common illnesses of which it increases the occurrence and severity: * Among infants and children under five years, excluding neo-natal mortalityoccurrence and severity: approx.

7 45% of mortality due to common illnesses is attributed to deaths occur in moderately malnourished childrenoccurrence and severity: approx. 45% of mortality due to common illnesses is attributed to deaths occur in moderately malnourished childrenNutrition throughout the life-cycleExample: The life-cycle approach applied to micronutrient deficiencyThe concept of the 1000 days windowof opportunity Undernutrition often starts in utero when mothers are malnourished and /or stunted : intra-uterine growthretardation Undernutrition impairs physical growth and cognitive developmentdevelopment After the age of 2 years damage is usually irreversible Therefore it is crucial to fight malnutrition duringpregnancy and the first 2 years of the child, the 1000 days between conception and the child s second birthday Many preventive interventions target this period of time (see SUN initiative)Purpose of nutrition assessment at population level What proportion of the population is affected by malnutrition ?

8 How severely? Who, Where andWhen are population groups affected? age, sex, socio-economic or occupational status etc; is seasonality a factor? Is the problem worsening or improving (trends)? What are the causesof malnutrition ? What can be changed to reduce the prevalence of malnutrition ? Are interventions efficient to reduce the prevalence of malnutrition ? (impact assessment)Note : While food insecurity is often assessed at household level, nutrition is defined at individual levelTypes of indicators of nutritional status Clinical indicators Marasmus and Kwashiorkor (oedema) Goiter Xerophtalmia Xerophtalmia Anthropometric indicators (based on body measurements) Biochemical I: Anthropometricmeasurementsand indicatorsMeasurements, indices and indicators Measurements of body dimensions cannot be interpreted directly Indices have a biological interpretation.

9 Height for age they can be expressed in comparison to a reference population (standard deviation from the median of a they can be expressed in comparison to a reference population (standard deviation from the median of a reference population = standard) indicators : a cut-point for the index is defined, differentiating normal and at risk individuals the indicator is the % of individuals below (or above) the cut-point The most commonly used body measurements and indices derived Weight: birth weight weight for age Height: height for age height for age weight for height body mass index Mid upper arm circumference (MUAC) Waist circumferenceOn the basis of the indices, indicators are defined that correspond to a state of malnutritionInfant and young child anthropometric indices and indicators of undernutritionWasting: low weight-for-height is a sign of acute malnutrition :Indicator = prevalence of wastingStunting: low height-for-age is a sign of chronic malnutrition :Indicator = prevalence of stuntingUnderweight: low weight-for-age is a sign of acute or chronic malnutrition or both.)

10 Indicator = prevalence of underweightUnderweight is an internationally recognized public health indicator for monitoring nutritional status and health in populationsMUAC is also used to assess acute malnutrition , especially in situations where it is difficult to weigh childrenMeasuringinfants and youngchildren Measurements need to be exact and precise Strict protocol for taking measurements Sources of error are many Imprecise age is a source of error Imprecise age is a source of error Personnel needs to be skilled There exist standard tests for checking the skills of personnel at the start of a survey Some checks of the validity of the collected data are possibleHow do we measure height/length?Children under 2 yearsChildren from 2 years29 How to weigh children?Using a hanging scaleUsing an electronic scale30 For infants and youngchildrenindicatorsbasedon height and weight cannot beinterpretedwithout sex* Sex of the infant/childis neededto interpretindices of height-for-age, weight-for-age and weight-for-heightweight-for-height Precise age is neededfor height-for-age, weight-for-age* Age is not neededfor weight-for-height* If the child doesn t have a valid birth certificate an historical calendar will be usedto identify the date of birth (see FAO guidelines for determining of age of infants and young children=Mid-Upper Arm Circumference (MUAC) of children 6-60 monthsSee: emergency situations use of the 3 colored tape.)