Unit 7 Utilisation of Food: Nutrition, Health, Culture, Economics Flashcards
“Undernutrition”
“Acute undernutrition” -diagnosis?
“Chronic undernutrition” - diagnosis?
“Micronutrient malnutrition”: consequences?
• Undernutrition: “the outcome of insufficient food intake, inadequate care and infectious diseases. It includes being underweight for one’s age, too short for one’s age (stunting), dangerously thin for one’s height (wasting) and deficient in vitamins and minerals (micronutrient deficiencies).’ (UNICEF (2009)
• Acute undernutrition: short, potentially reversible;
o Diagnosis: wasting, low MUAC (children); low BMI (adults
o SAM without oedema (swelling) = marasmus
o Oedematous SAM = kwashiorkor
• Chronic undernutrition: long-term
o Diagnosis: stunting
o Critical period: first 1000 days of life
• Micronutrient malnutrition:
o Usually chronic
o Acute (in humanitarian emergencies): scurvy (lack of vitamin C), pellagra (lack of niacin), beri-beri (thiamine)
7.1
Z scores, and technical challenges related to use of z scores
Cut-off points of measures given by WHO / UNICEF; wasting and stunting: within 2-3 z scores: moderate; 3+ : severe
Z scores measure relationships to variable in reference population (well-nourished children) /SD from mean
(observed value – median value of reference population) / SD of reference population
Technical challenges related to use of Z scores:
• Which reference population? Til recently: USA; now (WHO): multi-country; rarely: own standards
• No consensus on standards for older children and adults
• Reality: non-normal distribution; populations composed of sub-populations, thus validity of choice of cut-offs questioned
• Use of z scores as cut-offs (instead of percentiles): nice round numbers; but percentiles increasingly used (easier to understand)
7.1
Controversies in measuring undernutrition
- Are universal growth standards appropriate? Aren’t some ethnic groups naturally smaller?
Genetic difference mainly in adults; children’s difference mostly due to environmental factors, not genetic
• WHO /UNICEF firmly favour universal growth standards, inter-ethnic differences are small
Cut-offs should be different: sensitive where median is close to cut off
• E.g. South Asia (India): 50% classified as stunted, but tiny reference shift leads to large drop
Adults: genetic differences, some groups are tall but skinny (e.g. pastoralists in East Africa) – requires weighting of indices
BMI cut-offs for overweight too high for some Asian populations (“normal” weights but high fat and overweight-related diseases) –> country to decide on appropriate cut-offs - “Small but healthy” hypothesis (80s/90a): it’s adaptive to grow up small so they will need less food as adults
Adaptive but not desirable! Findings: poor growth as survival strategy comes at cost:
• Susceptibility to infections, mortality, human capital loss, lower competitiveness in modern world
• Consensus on use of universal growth standards for young children, necessary to intervene
7.1
Global prevalence and trends in undernutrition, acute malnutrition, chronic undernutrition, and micronutrient deficiencies
Undernutrition: gradual decrease but remains very high
o 27% moderately/severely stunted children worldwide
o 16% underweight
o 15% low birth weight
Acute malnutrition
o Global Acute Malnutrition – GAM approximates prevalence of moderate and severe wasting, but also includes children with low MUAC
o Integrated Phase Classification (IPC) for food insecurity, classifies:
3-10%= moderate insecurity, 10-15% = crisis, over 15%= emergency (see map 7.1.22.1)
25 countries in crisis or emergency
32 countries have wasting prevalence of 10%, requiring immediate intervention
Chronic undernutrition:
o 200 MM children moderately/severely stunted;
o 80% in 24 countries; highest % in SSA countries, India, Nepal, Pakistan, Bangladesh (see 7.1.2.2)
Micronutrient deficiencies – top 6, prevalence deficiency disorders
o Iron 2 BB affected Anaemia , reduced learning/work capacity, infant mortality, LBW
o Vitamin A 250 MM children Night blindness, eye drying, mortality in children and pregnant women
o Iodine 2 BB at risk Goitre, risk of stillbirth, birth defects, infant mortality, cog. impairment
o Zinc high in LDC Poor pregnancy outcome, stunting, genetic disorders, less resistance
o Vitamin B1 – Thiamine n/a; famines Beriberi (cardiac, neurologic), confusion, paralysis
o Vitamin B3 – Niacin n/a; famines Pellagra (dermatitis, diarrhea, dementia, death)
o Vitamin C famines, displaced Scurvy (fatigue, hemorrhages, low resistance to infection, anemia
Trends in prevalence of undernutrition: STUNTING 1985-2011:
o reduced from 47% to 30%, with largest improvement in China/Asia, Brazil, Tunisia
o increased in 17 countries, most in SSA (recession 80s, 90s), now slowly improving
7.1.2
Debates about when to intervene in acute malnutrition
1- Inappropriate: country sovereignty / labeling issue VS. unethical, “normalization of crisis”
2- Are interventions available, will they solve the problem? (e.g. might have long-term structural issues)
3- Immense level of resources required to tackle every crisis – but has high payoff for development!
7.1.2
Negative consequences of undernutrition
(1) Child morbidity and mortality
• Child undernutrition causes illness, pain, suffering, mortality
• Child undernutrition contributes to mortality from diseases by 73% (diarrhea), 47% (measles), 45% (severe neonatal infections), 44% (pneumonia), 36% (other infections) (figure 7.1.3.1)
• Cautionary note: linkages not clear; understanding of child death/illness requires further research.
(2) Long-term health and wellbeing effects
• Complex effects, mechanisms not well understood – area of active research and debate
• CHRONIC UNDERNUTRITION – adverse long-term effects, most irreversible; height-for-age at 2 years is best predictor of human capital (Victoria et al 08); stunting can be caused by wasting.
o 1- Shorter adult height (might catch up later)
o 2- Lower levels of education (poor brain development –> cognitive impairment) and social
o 3- Reduced economic productivity and lower wages (in manual jobs as well as those requiring education) Psychological effects of stunting: low self-efficacy, self-esteem, educational aspirations – correlated with earnings; Functional isolation hypothesis: undernourished children are less active etc., thus isolated form peers, get lower attention, leading to lower social and educational outcomes; social stimulation of undernourished children improves social and educational outcomes)
o 4- Lower birthweight of women’s own children, increased risk in pregnancy and childbirth
o 5- Susceptibility of rapid weight gain in later childhood, obesity-related diseases in adulthood
• ACUTE MALNUTRITION – increases risk of child illness and death
o Long –term effects poorly understood, could include long-term cognitive deficits, reduced school achievements, but difficult to distinguish from effects of chronic undernutrition.
o Study in Senegal: ex-SAM children have more minor illnesses than their non-SAM siblings; both sibilings were stunted and had more health problems than healthy control group. Implies possibility of full recovery from SAM.
7.1.3
UNICEF Framework on causes of child malnutrition
• Potential resources: environment, technology, people
o Political, cultural, religious, economic and social systems limiting use of potential resources (e.g. women’s status) ->
• BASIC CAUSES IN SOCIETY (community/national level):
o Quantity and quality of actual resources (human, economic, organisational) and way they are controlled
o Inadequate and / or inappropriate knowledge and discriminatory attitudes (e.g. poor economic status, social deprivation, illiteracy) limit hh access to actual resources ->
• UNDERLYING CAUSES (household/family level) – risk factors:
o Insufficient access to FOOD (Seasonality, shortages)
o Inadequate maternal and child CARING practices (breast feeding)
o Poor water/sanitation and inadequate HEALTH services – “WASH”
• IMMEDIATE CAUSES: o Inadequate dietary intake (monotonous diet, low diversity) o Disease (acute infection, chronic infection leads to increased demand; diarrhea leads to malabsorption
• OUTCOMES:
o Child undernutrition
o Disability
o Death
(- Framework neglects pre-existing condition, e.g. IUG growth restrictions, premature birth, due to poor health of mother
- Concentrates on individual / hh issues, not broader public factors (e.g. water/sanitation/health services, SP, social factors such as women’s status))
7.1.4
3 Causes of undernutrition
Evidence
Economic perspective
(1) POVERTY (Access)
Evidence:
o level of undernutrition lower in wealthier countries (7.1.4.1 – e.g. Niger: 80% extreme poor, 40% malnourished; Colombia: 15% extreme poverty, 5% malnourished; outliers: e.g. Yemen: 15% extreme poverty, 45% malnourished)
o household income growth explains 30-50% of reductions in undernutrition (Haddad et al 2003) (varies by country)
o BUT: undernutrition levels increase with hh poverty but undernutrition persists in higher income groups – Factors other than poverty/access play a role (India richest quintile 25% stunting, poorest quintile 60% - 7.1.2.4)
(2) IMMEDIATE causes (“proximate”) – approach focusing on treating symptoms (health workers)
1- Lack of essential NUTRIENTS
o Dietary nutritional requirements vary by individual (age, size, sex, activity, pregnancy, illness/HIV); international standards set by UN; Use: to estimate food security in population; estimate amounts of foods needed (e.g. dependent groups – refugee, prisons, hospitals)
Dietary energy: mostly from carbs (starchy stables – maize, wheat, rice…); poor shift to carbs to satisfy hunger; share of energy obtained from staple foods reflects “nutritional sufficiency”. Ultra-poor: even short in starchy staples.
Protein: (meat, fish, dairy, pulses, nuts; LDC: mainly plant based, from cereals source; for growth and development; UN standards on protein intake dated (1985) due to disagreement; complex linkages: intake, absorption, use; microbiome (intestinal flora) research in progress.
Vitamins and minerals: Iron (meat, fish, green leafies), Vitamin A (green, yellow fruit); dietary diversity as proxy indicator for micronutrients in diets
Food storage and preparation: eliminates toxins (e.g. soaking, drying), increases nutrients (soak maize in lime water); storage reduces nutrients, increase toxins from fungal infections.
2- ILLNESS and undernutrition
o “malnutrition-infection cycle”: Inadequate diet -–> weight loss, reduced immunity, mucosal damage –> Infectious disease -> inability to eat, digest nutrients –> reduced dietary intake; fever increases nutritional requirements; vicious cycle, death
3- MICRONUTRIENTS and illness
o Micronutrients support antibody formation, develop immune system and epithelium (defence against disease)
o Deficiencies increase risk of infectious disease, susceptibility to disease
Vitamin A deficiency: diarrhea, respiratory/ear infections, mortality; linked to measles –> existing deficiency exacerbated, death and risk of death
Iron deficiency: lowers defences, diminishes body and brain functions (BUT enables growth of microorganisms, e.g. malaria)
Zinc: deficiency growth retardation, malabsorbtion, foetal loss, neonatal death, congenital abnormalies; zinc reduces diarrhea, pneumonia, malaria and related stunting.
(3) The UNDERLYING determinants of undernutrition – approach of improving food security issues
• Treating security issues (underlying causes) vs. symptoms (immediate causes): little integration of perspectives
• Step forward: frameworks to link immediate and underlying (risk factor) causes for disciplinary/sectoral integration, as basis to test importance of different risk factors and interaction (focus scarce resources highest risks affecting many).
o MOSLEY AND CHEN’s FRAMEWORK on child mortality; 5 exhaustive categories of 14 proximate determinants for undernutrition: 1) maternal factors, 2) environmental contamination, 3) nutrient deficiency, 4) injury, 5) personal illness control; determine risk of falling sick (1-5), and rate of recovery (5).
o UNICEF 1990 FRAMEWORK (separate slide) is most-widely accepted
• Economic perspective: main determinants of undernutrition?
o Health environment, women’s education / status, per capita availability (Smith and Haddad 1999)
o Hh income, educational level of parents, WAS, living in urban areas (Charmarbagwala et al 2004)
o Further research needed but models drive policy: resource allocation, CBA, cost-effectiveness
7.1.4
FAO: impact of hunger and malnutrition throughout the life cycle
a) Woman undernourished
inadequate foetal nutrition, intrauterine growth restriction
b) Baby low birthweight
higher mortality rate
impaired mental development
increased adult chronic disease
c) Untimely, inadequate weaning
frequent infection
inadequate catch-up growth
inadequate food, health and care
UNICEF, WHO recommend early and exclusive breastfeeding up to 6 months for more nutrients, antibodies for short- and long-term benefits; avoidance of contaminated water *
d) Child past most dangerous effects, but cognitive, social, psychological effects of earlier undernutrition
reduced mental capacity
Adolescent stunted
reduced physical capacity and fat-free mass
inadequate food, health and care
e) Early marriage and adolescent child birth common, low weight gain in pregnancy
higher maternal mortality
a) Woman undernourished
inadequate food, health and care
f) Older people malnourished, knock-on effect on hh income, economic productivity, energy levels
reduced capacity to care for child
b) Baby low birthweight…
7.1.5
Reasons for suboptimal breastfeeding, consequences, evidence
• *Reasons for suboptimal breastfeeding:
o Erroneous belief that it’s insufficient; but colostrums contains vital antibodies
o Pain, discomfort, no support and advice
o Pressure to work
o Not having enough breastmilk: severely undernourished mother (not very common)
o Commercial promotion of formula milk incl. by health staff
• Consequences of suboptimal breastfeeding: 1.4mm deaths/year, 10% of disease burden in young children.
• Weaning period = transition to solid food: most risky (sanitation);need complementary, nutritious foods, not available in poor hh. Inadequate food is fed to infant; 6-24 months need complementary feeding and breastmilk up to 2 years or more; but in practice, weaning starts much earlier, increasing risks and lowering nutrition (7.1.5.3)
• Evidence: Z-scores from 54 low and middle income countries: South Asia: most stunted at birth; south Asia and SSA at 24 months; at 3-24 months, stunting gets steadily worse -> critical period = 1000 first days of life! (conception up to 2 years)
The economic perspective: The cost of undernutrition to national economies
o Copenhagen consensus: international exercise for CE of interventions
o 3 Causes of economic costs: direct resource costs (health care services, caregiver schooling and employment); direct losses in physical productivity; indirect losses from poor cognitive losses and loss in schooling
o Difficulty: data, causality
o Conclusions: substantial economic costs; individual productivity loss: over 10% in lifetime earnings; GDP: 2-3% loss; India: 3% GDP loss due to productivity loss …
7.1.5
Nutrition transition
Before After
Local markets Supermarkets, industrially produced food
Unprocessed processed, pre-cooked, packaging and branding
Seasonally available Year-round availability
Non-sweetened drinks Sweetened drinks (40% Mexican adults: soft drinks =10% dietary energy)
Low meat, fat, sugar High meat, fat, sugar;
Physical exercise Low physical exercise due to urbanization, changing work patterns, technology (transport, food processing)
FAO estimates increase in per capita food (energy) consumption in LDCs between 1970 (2100) and 2015 (2800)
Decrease in cereals, roots, tubers; increase in meat, oils/fats, milk and milk products, refined sugar
7.2
9 Global trends driving changing diets
- Urbanization and effects: increased eating out, decreased physical activity
- Economic growth, household wealth
- Openness of markets
- Decade-long trend: food cheaper in relation to income (though food prices rising recently)
- Opportunity cost of preparing and obtaining food increases due to women working
- Storage and handling technologies (refrigeration) for long shelf life, year-round availability
- Marketing of fresh products: meat, fish
- Globalisation of food production, marketing, global brands
- Media, advertising power to influence tastes
Popkin:
• Humans evolved to prefer sugary, fatty foods (scarcity before). Increased buying power, media, marketing,… consumption of such foods exploded; consumption patterns in middle income countries rapidly moving towards Western diets.
Health implications of changing diets
Overweight/obesity
o Low exercise, high fat and sugar -> overweight / obesity
o LBW -> tendency to adult overweight and diseases -> contributes to rapid obesity rise in countries of historical undernutrition;
o Barnett: high body weight sign of wealth and health and female beauty in many cultures -> more obesity in
o women; e.g. Mexican women’s BMI from normal to overweight in 20 years 1988-2006
NCDs (Non Communicable Diseases, “disease of affluence”)
o Diabetes, cardiovascular disease, stroke, cancers
o Due to
high meat/fat/sugar/salt diet -> high blood pressure, blood glucose, cholesterol, low vitamins
Obesity, insufficient physical exercise (90% of type 2 diabetes due to excess weight)
o second after child undernutrition cause of DALY (7.2.2.3)
o Now spreading rapidly in rural developing country areas, e.g. 6 SSA countries undergoing nutrition transition; in rural Bangladesh sharp increase in cardiovascular disease and cancer deaths (1986-2006) NCDs
o Effect on children: type 2 diabetes becoming more common in children
USA: may be first generation of reduced life expectancy compared to parents’
Middle income /wealthier in poor countries following trend
Undernutrition in micronutrients at the same time overfed; high caries in middle income countries
7.2.2
Dual crisis of obesity and undernutrition: Evidence and causes/predictors
• Evidence
o 1/5 to 2/3 of households (in seven low-income countries) that have an underweight person also have an overweight person
o Middle income countries mostly affected of “dual burden”; mostly 1+ overweight adult and 1+ underweight child.
o E.g. India: Mother’s underweight has worst stunting/wasting/underweight outcome for children; Mother’s overweight still has high undernourishment outcome, e.g. 30% stunting incidence, 20% underweight
• Causes of dual burden: debated; predictors:
o Maternal short stature
o Large family size
o Foetal programming: exposure to low micronutrients and high energy diets = rapid weight gain
o Child illness or maternal depression or microbiomes differences cause child under nutrition
7.2.2
