Metrics for Food Security & Undernutrition

Metrics for Food Security & Undernutrition

Outline • Information requirements for Policy • Approaches to measure food insecurity and under nutrition • FAO Indicators of undernourishment & assessment • Household food consumption surveys& assessment • Childhood anthropometrics& assessment • Food Security Statistics Metrics for Food Security & Undernutrtion

Food Security • The World Food Summit in 1996: “Food security exists when all people, at all times, have physical and economic access to sufficient, safe, and nutritious food to meet their dietary needs and food preferences for an active and healthy life.” • Multidimensions : (i) level and stability of food access and availability, and (ii) adequacy of food use and nutritional status. • Question: How do we measure these dimensions? Metrics for Food Security & Undernutrtion

Levels of Food Insecurity Metrics for Food Security & Undernutrtion

Hunger • Hunger: A sensation of not having enough to eat. • Extent of hunger: Lack of essential nutrients in the diet ; a major indicator - food energy deficiency. • Hunger could be due to one’s inability to absorb and use food energy and specific nutrients for body functions = > overall nutritional status is also affected by people’s health. Metrics for Food Security & Undernutrtion

Information Requirements for Policy • Estimate of food emergency due to a sudden drop in supply or access to food; people’s immediate needs of essential nutrients to ensure survival. • Estimate of chronic food insecurity caused by long term food deprivation due to structural poverty and poor nutrition. Metrics for Food Security & Undernutrtion

Comprehensive Assessment needs • Measurement: • Who are the food insecure? • How many are they? • Where do they live? • For effective policies, one needs to know: • What causes people to be food insecure? • What is the impact of programs and policies to address their food insecurity? Metrics for Food Security & Undernutrtion

Approaches to Measure Food Insecurity and Under nutrition • FAO Indicators of undernourishment • Household food consumption surveys, and • Childhood anthropometrics. Metrics for Food Security & Undernutrtion

FAO Indicator of Undernourishment • Prevalence of undernourishment: • Proportion of population not meeting minimum food energy requirements. • Estimator: • Per capita calorie availability, • Inequality in access to those calories among the country’s population, • Mean minimum amount of calories required. Metrics for Food Security & Undernutrtion

FAO Indicator • Data Sources • Food available for human consumption: National food balance sheets (FBS) = f(production, trade, stock changes, non-food uses, and extra-household waste) • Per capita calorie availability: Using Food composition tables, convert food quantity into calories divided by the population (per capita dietary energy supply (DES)(kilocalories per day). Metrics for Food Security & Undernutrtion

FAO Indicator Inequality in access to calories: • Assume a log-normal distribution function specified by mean DES and the coefficient of • variation (CV). • CV is derived from sample distributions of calorie consumption or food expenditures from available household surveys. Metrics for Food Security & Undernutrtion

FAO Indicator • Minimum dietary energy requirement (MDER): • Amount of food energy needed, in order to maintain an acceptable minimum body weight, body composition, and a level of minimum (‘sedentary’) physical activity, consistent with long-term good health. Metrics for Food Security & Undernutrtion

Source: FAO Metrics for Food Security & Undernutrtion

FAO Indicator: Assessment • Objective: • Inform the global community about levels and trends of undernourishment; facilitate global and regional governance of food security. • Track progress towards the first millennium development goal (MDG). • A measure of chronic food insecurity at national levels. • Does not provide information on distribution of the number of hungry. • Does not address policy issues. Metrics for Food Security & Undernutrtion

FAO Indicator: Strengths & Limitations • Strength: Global coverage • Limitations: Mean dietary energy supply (DES): • How comprehensive is food energy deficiency as an indicator of food insecurity? • How accurate are the estimates? IFPRI study of 12 African countries show FAO numbers to be underestimates. Metrics for Food Security & Undernutrtion

FAO Indicator: Strengths & Limitations • Coefficient of Variation: • FAO estimate is an overestimate. • Most importantly, it is kept invariant though (i) income and expenditure inequalities have increased in most developing countries between the early 1980s and mid-1990s; (ii) given Engels’ law and growing income, CV in calorie intake would decline. • Conceptually a constant CV implies the premise that undernourishment is a function of DES only. • Is it an appropriate measure? CV is sensitive to shape in the upper end of the distribution. Metrics for Food Security & Undernutrtion

FAO Indicator: Strengths & Limitations • Minimum Dietary Energy Requirement (MDER): Consumption level that balances energy expenditure. How valid are the assumptions with respect to different age-gender composition? How good is this approximation? • Energy Expenditure = Basal metabolic rate (BMR), the energy needed for digesting food, metabolizing food, and storing an increased food intake, and the energy required for performing physical activity; it ranges between 1300 & 1700 kcal/day for adults, depending on age, sex, height, and body weight; an additional 50% for light physical activity for male & female adults. Metrics for Food Security & Undernutrtion

FAO Indicator: Strengths & Limitations • Estimates often are not based on current estimates of FBS data but projections. • Estimates are not robust with respect to DES, CV & MDER parameters. • The elasticities of the global estimates of undernourished with regard to national DES, CV, and MDER are 4.8, 1.6, and 4.7. Metrics for Food Security & Undernutrtion

Metrics for Food Security & Undernutrtion

Household Food Consumption Surveys (HFCS) • Nationally representative household surveys: Designed and undertaken by country’s statistical office, sometimes supported by other national and international organizations. • Sample size ranges from a few thousand up to more than 100,000 households. • Generally such survey estimates are available in respective country statistical offices or the World Bank (http://www.worldbank.org/lsms). • Countries differ with respect to frequency of such surveys; Indian experience and illustrations. Metrics for Food Security & Undernutrtion

HFCS: Salient Features • Indian NSS data: Salient Features • Household consumption surveys: • Reference period: HFCS use 14 or 30 day recall periods for food items; longer recall periods would involve unacceptable inaccuracies. Surveys with shorter recall periods, say a 7-day recall period, are preferable from a nutritional perspective. Metrics for Food Security & Undernutrtion

HFCS: Salient Features • Household consumption surveys: • Estimates of undernourishment: Use food composition tables & convert data on the quantity of different food items consumed to calories to get an estimate of household calorie consumption. By comparing these consumption estimates with energy requirement cutoffs, which consider the age and sex structure of the household, one can identify households with undernourished members. Metrics for Food Security & Undernutrtion

HFCS: Strengths & Weaknesses • Strengths: • Estimates are relatively more accurate than those from macro FBS data. • Direct estimates. • Disaggregate information permits greater precision. • No assumption on demographic composition; instead actual profile is considered in estimation. • Permits ‘hunger mapping’, that is, food insecurity profiles across socioeconomic or geographic divisions . • No distributional assumption involved; non-parametric method. • Information on socio economic characteristics permit analysis of determinants of food insecurity. Metrics for Food Security & Undernutrtion

HFCS: Strengths & Weaknesses • Strengths: Permits to estimate income and price responsiveness of food energy and nutrient consumption, a tool required to predict nutritional impacts of policies and external shocks or simulate the impact of food price or food supply shocks on food insecurity by population groups. Metrics for Food Security & Undernutrtion

HFCS: Strengths & Weaknesses • Weaknesses: • Single round surveys will not capture seasonal variations; Solution: Annual survey based on moving reference period. • Estimates for individual households would still be biased. • Difficult to estimate calorie intakes from food consumed outside like restaurants and hostels. • Do not capture waste, losses, and non food use within households. • Non-sampling errors. Metrics for Food Security & Undernutrtion

HFCS: Assessment • Strengths: • Accurate data and no need for any assumption about distributions. • Policy relevant statistical profiles facilitate ‘hunger mapping’ and estimation of policy parameters like impact effectiveness of different policy options. • Weakness: • Problems of large scale data collection, processing and timely dissemination. • Even now periodic household income and consumption surveys are not periodic; hence, at best it can be complementary to the FAO approach. Metrics for Food Security & Undernutrtion

Anthropometric Measurements • FAO & HFCS approaches are based on food consumption estimates at the household level. • Anthropometric measures pertain to nutritional outcomes at the level of the individual. • Results between these two approaches can differ since food consumption is only one of the factors that determine individual level nutritional outcome. • Other factors: food losses, intra-household food distribution, individual health and activity levels. • The two approaches measure different concepts but are complementary. Metrics for Food Security & Undernutrtion

Anthropometric Measurements • Anthropometric measures: Broad range. • Most commonly used indicators: Relate to the height and weight of individuals. • Anthropometric indicators differ between adults and children since height does not change for the former. • Consensus: On anthropometric indicators for children aged 0–5. Metrics for Food Security & Undernutrtion

Anthropometric Measurements • Three most commonly used indicators – child stunting, wasting, and underweight. • Offer insights into different dimensions of nutritional problems. Wasting (low weight for height): An indicator of acute undernutrition – relevant to monitor acute food shortages, • Stunting (low height for age): An indicator of chronic undernutrition, • Underweight (low weight for age): Summary indicator combining both facets. Metrics for Food Security & Undernutrtion

Anthropometric Measurements • Data sources: Demographic and Health Surveys (DHS) and related Multiple Indicator Cluster Surveys (MICS). • Standardized protocol to measure and weigh children; they are always based on national random samples, whereby sample sizes vary from around 3000 to over 100,000 children. • Generally DHS and MICS cannot be merged with data from household consumption surveys – different samples by different organizations. Metrics for Food Security & Undernutrtion

Anthropometric Measurements Advantages: • A direct measure of how undernutrition affects the health and well-being of individuals • Because undernutrition that generates poor anthropometric outcomes contributes to higher morbidity and mortality. • Three different child anthropometric indicators together indicate both chronic and acute undernutrition. • Relief organizations use childhood anthropometry to monitor the success of relief operations in emergency situations. • Estimates, as based on household survey data, permit (i) profiles of undernutrition by groups and regions; and (ii) identify groups and localities particularly affected. Metrics for Food Security & Undernutrtion

Anthropometric Measurements Advantages: • Survey data permit study of determinants and hence, policy imperatives; facilitate design and monitoring of nutrition interventions. • Facilitate monitoring of childhood anthropometry across space and time. Metrics for Food Security & Undernutrtion

Anthropometric Measurements Problems: • Identification of the cause can be a problem since poor anthropometry could be due to other factors. • DHS or MICS surveys are not periodic; hence useful for medium term assessment and not for identifying short-term crises or annual monitoring. • Permits focus on children only. Metrics for Food Security & Undernutrtion

Anthropometric Measurements Problems: • Nutrition transition and implications. • Genetic differences in height and weight ; its implications. Metrics for Food Security & Undernutrtion

Food Security Statistics http://www.fao.org/economic/ess/ess-fs/fs-data/ess-fadata/en/

Food Security Statistics

Food Deprivation • Prevalence of undernourishment in total population (percentage): Proportion of the population in a condition of undernourishment. Food Security Statistics

Food Deprivation • Undernourishment:Undernourishment refers to the condition of people whose dietary energy consumption is continuously below a minimum dietary energy requirement for maintaining a healthy life and carrying out a light physical activity with an acceptable minimum body-weight for attained-height. Food Security Statistics

Food Deprivation • Depth of hunger (intensity of food deprivation):The intensity of food deprivation indicates how much food-deprived people falls short, on average, of minimum food needs in terms of dietary energy. It is measured as the difference between the minimum dietary energy and the average dietary energy intake of the undernourished population (food-deprived). The intensity of food deprivation is low when it is less than 200 kilocalories per person per day and high when it is higher than 300 kilocalories per person per day. The greater the food deficit, the greater the susceptibility for health risks related to undernutrition. Metrics for Food Security & Undernutrtion

Food Needs Minimum Dietary Energy Requirement (kcal/person/day) • Most significant updates on undernourishment estimates are the new standards for human energy requirements released in 2004 by FAO, WHO and UNU as well as the new standards of Body Mass Index released in 2006 by WHO. • These new standards, used for the first time in SOFI 2008, affect the minimum dietary energy requirements (MDER) established by FAO. MDER is a crucial factor in FAO’s undernourishment methodology, as it establishes a cut-off point, or threshold, to estimate the prevalence (percentage) of the undernourished population in a country. When the threshold, or cut-off point changes, so does the prevalence of people estimated to be undernourished. Metrics for Food Security & Undernutrtion

Food Needs • Dietary energy requirements differ by gender and age, and for different levels of physical activity. • Accordingly, minimum dietary energy requirements, the amount of energy needed for light activity and minimum acceptable weight for attained-height, vary by country, and from year to year depending on the gender and age structure of the population. • For an entire population, the minimum energy requirement is the weighted average of the minimum energy requirements of the different gender-age groups in the population. It is expressed as kilocalories (kcal) per person per day. Metrics for Food Security & Undernutrtion

Exercises 1. Assess the dimension of food insecurity in Bangladesh with reference to its macro and spatial dimensions and their policy imperatives. 2. How relevant are the policy questions discussed in the international context to Bangladesh today? 3. What are the advantages of Bangladesh as a small country in terms of policy formulation and implementation for food insecurity? Metrics for Food Security & Undernutrtion

Reference: Haen, Hartwig de, Stephen Klasen, and Matin Qaim (2011): “What do we really know? Metrics for food insecurity and undernutrition”, Food Policy, Vol. 36, No. , pp. 760-769. Thank You

Metrics for Food Security & Undernutrition