Nutrition in Global Health Part 1: Roadmap to the world’s nutritional health: Causes, mechanisms, solutions Allan J Davison Ph. D, Professor, Biochemist, Faculty of Sciences, Simon Fraser University Department of Biomedical Sciences & Kinesiology June 2011 Prepared as part of an education project of the Global Health Education Consortium & collaborating partners
Nutrition in global health - Overview • Inequities in food distribution global hunger & starvation • One billion are too hungry to live productive lives - an equal number are adversely affected by overweight! • 6 major deficiencies impact health through the life cycle: water, protein, iron, vitamin A, iodine, folic acid • Childbearing women & their children are hardest hit Meanwhile, overnutrition & inactivity risk of heart disease, osteoporosis, cancer, diabetes, strokes, etc. Page 2
Fundamentals and emphasis – As we consider cause and effect we must ask: How & why have such inequities come to be? Who and what factors impede solutions? What current initiatives will bring the resolution? – To help answer these, we will emphasize: Immediate causes - scarcity of specific nutrients Primary and secondary prevention Public health approaches to solutions Page 3
Other GHEC modules contribute to our understanding of Nutrition in Global Health This module does not stand alone. “Roadmap to a world without hunger” will follow (see note) Two other GHEC modules deal with poverty & hunger a) Module 48: Acute malnutrition – Clinical aspects (deals with treatment) b) Why is the 3 rd world? (underlying and diverse causes of poverty & hunger) http: //globalhealthedu. org/resources/Pages/default. aspx To see this module in the context of what will follow, see Note A Page 4
Pre-quiz (pending completion of “quiz” feature in GHEC’s server) • As a reality check, and to create “teachable moments” for what follows, we now invite you to take a 5 -minute pre-quiz • You will be offered 10 true-or-false questions to dispel some common misconceptions • Some of this misinformation is spread by those who have something to gain from it • After completing the pre-quiz, we hope you will continue this module with greater interest and renewed clarity Page 5
Learning objectives After completing this module you should be able to 1. Describe the extent of malnutrition & its impact on people of the planet, and understand how MDGs depend on nutrition 2. Analyze the factors that determine nutritional health 3. Identify nutritional problems among individuals & populations, identify causes & appropriate solutions 4. Assess risks at various stages of the life cycle & recommend strategies for diminishing risk 5. Compare competing theories accounting for the inequities 6. Predict outcomes by projecting current trends into the future & foresee a pathway toward a world without hunger Page 6
To get the most out of this module If you are…. . • a nutritionist or student of nutrition • a student of one of the health professions • planning a project in regions with severe nutritional problems • a public health practitioner You may want to … • Pay attention to global & public health & policy implications. • Pay attention to perspectives & realities in desperate situations • Emphasize check-lists to prepare for field work & gather information to recommend/advocate for intervention • Use these slides & resources in your information / teaching sessions Page 7
Preface: Nutrition is crucial to global health • Among the immediately modifiable factors that affect individual & public health … nutrition is of prime importance • Nutrition at every stage of life lays a foundation for health in the ensuing stage • For all nations, rich & poor, nutrition determines physical health & development through the life-cycle, including: – Success in childbearing, cognitive function, socio-economic independence, education, disease resistance & employability – Health & economic development are contingent on provision of adequate food, nutritional resources & support Page 8
A vicious cycle: economics, hunger, health Poverty diminished access to agricultural & food resources malnutrition Physical & cognitive impairment, susceptibility to disease, early death inability to earn an income Economic marginalization inability to provide for self or family Page 9
The Millennium Development Goals At a UN Millennium (2002) summit, the nations of the world set eight MDGs to be achieved by 2015 • The world's main development challenges were identified • Specific actions and targets (the MDGs) • A commitment to provide the means was made by 189 nations & signed by 147 heads of state The MDGs break down into • 21 quantifiable targets • Targets are measured by 60 time-lined indicators Some nations have kept their trust. But some of the richest in the world have announced that they will not meet their commitments Page 10
Nutrition & Millennium Development Goals Primary goal is to eradicate extreme poverty & hunger 1 see next 2 slides Nutrition – is a direct prerequisite to goals 1, 3, 4, 5 & 6; indirectly to 2, 7 & 8 Page 11
Centrality of nutrition to MDGs 1, 2, & 3 1. Eradicate extreme poverty & hunger. Poverty is the main determinant of hunger. In turn, malnutrition irreversibly compromises physical & cognitive development & thus transmits poverty & hunger to future generations. 2. Achieve universal primary education. Malnutrition diminishes the chance that a child will go to school, stay in school, or perform well in school 3. Promote gender equality, empower women. Women’s malnutrition impairs the whole family’s health & nutrition Page 12
Centrality of nutrition to MDGs 4, 5, & 6 4. Reduce child mortality. Delivery of a live healthy child is dependent, above all, on a well nourished mother. Protein & folic acid are critical here 5. Improve maternal health. Malnutrition accentuates all major risk factors for maternal mortality, e. g. , inadequate protein, iron, iodine, vitamin A & calcium 6. Combat serious infectious diseases. Malnutrition aggravates infections, immune competence, transmission & mortality in HIV, malaria, tuberculosis Adapted from Gillespie and Haddad (2003) http: //web. worldbank. org/ Page 13
Slow progress toward the MDGs At mid -way, most MDGs are partly met. Only goal #2 is fully within reach! Page 14
Nutrition in Global Health Course overview 1. Overview of nutrition across humankind 2. 3. 4. 5. 6. Nutrition fundamentals in global context Top six nutrition problems, & their solutions Nutrition across the life cycle in rich & poor nations Cause & effect in population nutrition Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger Page 15
Universal limitations & health consequences • We can’t survive without about 15 essential mineral elements, so they are needed in our diets, most in trace amounts • We can’t manufacture about 15 vitamins, so they must be provided in our diets And in addition…… Page 16
Universal limitations & health consequences In addition: We lost key metabolic abilities our evolutionary ancestors had. Thus we are vulnerable to 2 dietary risks: 1) In early life – a period of rapid growth, we are vulnerable to “kwashiorkor” (protein insufficiency) because we can’t synthesize 8 “essential” amino acids missing from our diet 2) In later life: we are vulnerable to obesity & diabetes – in part because we can make fat from carbohydrate, but we can’t easily convert stored fats back to carbohydrates Note B Page 17
Categories of nutritional status Nutritional status is assessed as one of four categories 1. Good nutritional status: All nutrients (right quantities, time & place) allow optimal, growth, maintenance, & reproduction 2. Overnutrition: An excess of a nutrients (usually calories) is being consumed, so that health is negatively impacted 3. Undernutrition: Insufficient food is consumed to allow for the energy needs of the individual. Inevitably dietary (& then body) protein is burned for energy. A secondary protein deficiency ensues – thus: "protein-energy-malnutrition" 4. Malnutrition: Energy consumption is adequate, but there is an imbalance among constituents of the diet and health is impacted Note C Page 18
Worldwide distribution of malnutrition Over 20 million children suffer from acute malnutrition WHO. Scientific American, Sept 2007 Page 19
Worldwide, nutritional inequities follow poverty (as do health inequities & life expectancy) • Globally, there is plenty of food for everyone but …those who have more than they need find reasons not to share • The result – in the time you spend on this module over 1000 children will have died of hunger • Each day 1500 children go forever blind from lack of vitamin A • The poorest are 50 -200 x more likely to die in pregnancy (more than half these deaths are attributable to iron deficiency). • About 2 billion people (56% of pregnant women) have iron deficiency. Their babies have low birth-weight, & mortality Note D Page 20
“The bottom billion” (title of a book by Paul Collier ) “The poorest of the poor” - Public health nutritionists identify a subclass of the hungry - those who try to survive on resources worth less than $1 per day • We define this subclass as people who don't get enough to meet the ordinary demands of life • They lack the resources to earn a living, or obtain what’s needed for normal, growth, maintenance & reproduction • It goes without saying that they are unable to provide the necessities for those who depend on them Page 21
“The bottom billion” (title of a book by Paul Collier ) • Their lack of access to resources is such that a significant fraction will be unable to stay alive • They live mostly in isolated rural areas and most are subsistence farmers This means that what they eat this month is what they can take out of the ground from last month's planting Page 22
Unhelpful misconceptions about aid False: “Most aid money goes into the Swiss bank accounts of corrupt African dictators” “Aid creates dependence & impedes self-sufficiency” “Despite all the aid $, the problems are only getting worse” The truth is: Overwhelmingly African leaders are not corrupt. When they are, most bribes come from the West Well planned aid builds capacity & self-sufficiency Overall, hunger worldwide is diminishing. MDGs go forward because of the countries that honour their pledges! Note E Page 23
Money? Useless - no nearby shops • It’s hard to imagine a malnourished community and you may want to experience field conditions in advance No commerce! Try it at a Medecins sans Frontieres site: http: //www. starvedforattention. org/ • No shops to spend money in, no one to employ anyone, no one to sell things to • Hungry children are all too visible, and those who didn’t survive are in tiny unmarked graves Their needs are much more immediate than money We don’t need studies to learn what they need - read on! Page 24
If they don’t need money – what do they need? • Short term they likely need emergency rations, safe water In conflict zones, shelter & safety to live, plant, harvest • Medium term they need to become self-sufficient, with: good seeds, fertilizer, usable water, sanitation, low technology agricultural info & resources, health services, mosquito nets, pharmaceuticals • Long term they need the prerequisites of sustainable economic development - tools for development – see Part 2 • Kids need particular attention – see note below & later slides Note F Page 25
The goal is to see everyone self-sufficient • People in the poverty trap live from hand to mouth, with no opportunity to put resources aside to build a better future • Such communities cannot access the ladder of economic development without external help. • The MDG promises of 0. 7% of rich country GDP for aid was chosen to eliminate extreme poverty & hunger in 3 decades • But there are many nations that failed to meet this goal, including both the US and Canada • Thanks to the nations that keep their promises, widespread hunger may be eliminated, but only after 30 -50 years. This not, however, cause for undiluted joy. See Note G Page 26
Some communities subsist in the “poverty trap” • Even among the richest there are some individuals so marginalized that there seems little hope for them The larger culture, if it is compassionate, takes long-term responsibility for ensuring them the necessities of life • Globally there are communities that have been denied the resources to ever become wealthy. Often from geography, climate, invasion, or appropriation of their natural resources Regardless, a world community of compassion can provide the necessities of life, & offer new life to the dispossessed, as North America once opened its doors to the poor Note H Page 27
Nutrition in Global Health Causes, mechanisms, solutions Nutrition is crucial to global health & MDGs 1. 2. 3. 4. 5. 6. Overview of nutrition across humankind Human nutrition fundamentals in global context Top Six nutrition problems, & their solutions Nutrition across the life cycle in rich & poor nations Cause & effect in population nutrition Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger Page 28
Human Nutrition Fundamentals in Global Context The next set of slides covers the critical skill set needed for understanding nutritional issues in the context of global health They are not a substitute for nutritional training, but rather a catalog of nutritional tools applicable to problems a health practitioner might encounter in the field From this you can learn when to call in a nutritional expert, what kind, & what to you might reasonably ask for & receive If you have learned nutrition in a developed country, this may help you to expand your knowledge of nutrition and public health in the context of 3 rd world health problems Page 29
Dietary patterns across cultures 1. Hunter gatherers – the earliest category Benefits: mixed diet, well nourished in good times Risks: famine or drought, warfare & plunder, resource depletion through population pressure Prevalent problems: starvation, thirst, life-expectancy Note I Page 30
Dietary patterns across cultures 2. Peasant agriculturalists – successful small scale farmers (currently the largest group) • Benefits: close to food sources; if no punitive taxes or rents; usually well adapted to their traditional diets • Risks: single crop emphasis malnutrition, plagues (locusts, rodents), exploitation, warfare and plunder • Prevalent problems: vitamin deficiency, starvation, alcoholism Page 31
Dietary patterns across cultures 3. Indigent, landless crop planters Benefits: Community, share with family, neighbors, income is typically less than a dollar a day Risks: Crop failure, drought or famine, erosion, soilexhaustion, pestilence, economic exploitation (by landlords, seed providers, loan-sharks), displacement, forced migration, civil unrest or foreign invasion Problems: multiple vitamin deficiencies, kwashiorkor (protein malnutrition), infectious disease epidemics. Too poor, powerless to help themselves, most of them will never escape their circumstances, nor achieve full health Page 32
Dietary patterns across cultures 4. Urban slum dwellers – fastest growing group Benefits: hope for jobs, escape from drought or crop failure Risks: overcrowding, poverty, poor hygiene, limited food choice, social disruption loss of traditional diets, crime Prevalent problems: deficiencies of essential nutrients, alcoholism, obesity, kwashiorkor, epidemics Page 33
Dietary patterns across cultures 5. Affluent urbanites – most recent category Benefits: many food choices (appropriate and inappropriate) Risks: inactivity along with high fat, sugar, alcohol intakes Prevalent problems: overnutrition, obese babies and adults diabetes (carbohydrates), cholesterol, atheroma (lipid), strokes, heart disease diabetes, gout (uric acid - meat sources) Note J Page 34
Nutrition in Global Health Causes, mechanisms, solutions Nutrition is crucial to global health & MDGs 1. Overview of nutrition across humankind 2. Human nutrition fundamentals in global context 3. Top six nutrition problems & their solutions 4. Nutrition across the life cycle in rich & poor nations 5. Cause & effect in population nutrition 6. Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger 1. Page 35
Top 6 global manifestations of malnutrition We begin with a perspective, then we take each of the 6 in turn 1) Water is a food (“food” is the material we eat & drink”) In hot climates, we can die in a few hours from a lack of it 2) Protein-energy malnutrition • The machinery of life, sculpted from 20 different amino acids • Deficiency is most serious in children (time of fastest growth): "failure to thrive", stunted growth The material in this section is well reviewed at: http: //www. pitt. edu/~super 1/lecture/lec 0141/index. htm Iron, vitamin A, iodine – check the latest information at: http: //www. micronutrient. org/English/view. asp? x=1 Page 36
Top 6 global manifestations of malnutrition (cont. ) 3) Iron deficiency - prevalent in Africa and Asia • Women & children are the most seriously affected • In parts of Africa 60% of children have blood iron • About a quarter of these have symptoms of anaemia 4) Vitamin A deficiency Over 100 million children under 5 suffer vitamin A deficiency • In high deficiency areas vit. A tabs child mortality by >20% & child blindness by 80%. Night-blindness is an early sign Page 37
Top 6 global manifestations of malnutrition (cont. ) 5) Don’t underestimate iodine deficiency disorders • WHO 2003: “ 1. 6 billion people don’t get enough iodine”. This is the major cause of preventable brain damage. • Thanks to MDG programmes the problem is shrinking! http: //www. who. int/vmnis/iodine/status/en/index. html In addition nutrition determines chronic disease risk • Heart disease, osteoporosis, cancer, diabetes, strokes, etc. We’ll go through these one at a time in the following slides and Note K lists categories of at risk people across countries Note K Page 38
Top 6 global manifestations of malnutrition (cont. ) 6) Folic Acid is required for healthy babies • A deficiency causes spina-bifida – a common birth defect • Supplements are recommended before start of pregnancy • 50% of pregnancies are unintentional! Women who might become pregnant, need advice More details on these nutrients in the ensuing slides Page 39
Water: one of our most important foods • Adequate safe water is most important dietary component • 9 million worldwide have water-borne diseases • In India, contaminated water kills 300, 000 children annually • Problems relating to water supply & safety have simple, relatively inexpensive solutions • Water “ownership” is, however, contentious & usually follows military power (e. g. , in Middle East) • In hot humid conditions workers may need over 5 liters / day & to replace the Na. Cl lost along with water in sweat http: //www. who. int/water_sanitation_health/mdg 1/en/index. html Page 40
The special importance of proteins • Proteins are the machinery of life. We have no storage form. If we must use protein “stores”, tissues lose function • Plasma, liver and kidney lose function first. Their proteins are the most “labile”. Then, digestive tract, muscle & heart • Proteins are made up of 20 amino acids. 12 are non-essential and can be made from other dietary components • 8 amino acids are “essential”. If even one is missing, no protein can be synthesized. A protein lacking any one essential amino acid has zero “biological value Page 41
Dietary deficiency of proteins is deadly • When any essential amino acid is missing, all the rest are burned & no protein synthesis can occur – zero! • All essential aa’s must be there at the same time. Meeting an amino acid need one day later is useless • A diet previously adequate in essential amino acids becomes inadequate if non-essential amino acids are removed. Because, although the body can make missing non-essential aa, it uses up essential amino acids to do so • Protein complementarity, de-emphasized in nutrition courses, can be vital where protein intake is compromised Page 42
Humans adapt to low protein intakes. . . otherwise impact of protein deficiency would be even higher Endocrine changes improve the recycling of proteins. As tissues repair, the released amino acids are reused more efficiently • In the African presentation of kwashiorkor, a child is exposed to a protein deficient diet (ages 1 to 5) & adapts successfully • Then a 1 -week lack of protein (parent loses job, baby is fed glucose-water only, or a gastro-intestinal infection) kwash • Child is treated for kwash, sent back to home to same diet, & reaches adolescence, usually without recurrence. Page 43
Protein & energy nutrition are inseparable • When the diet lacks carbohydrates, it uses some amino acids to make glucose for brain, muscle, etc. • When a diet lacks total calories, proteins are co-opted, first dietary, then plasma, liver, kidney, etc. • For these reasons, a diet previously adequate in essential amino acids becomes inadequate if carbohydrate or calories are removed. • Do an internet search on “protein-sparing effects of carbohydrates” if you want to understand this further Page 44
Protein-energy malnutrition - in adults Tissues are raided, with the following consequences: • Loss of plasma proteins oedema* • Loss of liver & kidney function diminished inactivation & excretion of carcinogens and toxins • Loss of immune function gastro-intestinal infections • Loss of digestive tract / liver function amino acids can’t be utilized for proteins. No treatment can prevent death • Loss of muscle and heart tissue weakness, heart failure *Oedema or edema = abnormal accumulation of fluid beneath the skin or in body cavities Page 45
Hungry kids – difficulties in diagnosis • Marasmic babies may not seem undernourished until a check for “pitting oedema” reveals that what appear to be strong arms and legs, are in reality oedematous • Another diagnostic complication is that most deficiencies are combined, as in protein energy malnutrition (“PEM”) with multiple vitamin deficiencies • The distinctions are crucial both in determining treatment, and in determining if the underlying problem in the community is scarcity of food, a protein, or many nutrients Page 46
Protein malnutrition is different • In uncomplicated kwashiorkor, only protein is lacking - “Malnourished, not undernourished” • The risk of death or permanently retarded development is great, and the risk is increased because its easier to miss the diagnosis • Kwashiorkor babies may have more than adequate calories in their diets. They may be chubby, with substantial subcutaneous fat • Kwashiorkor may go unnoticed even when urgent hospitalization is needed, or when death is imminent Page 47
Protein malnutrition: diagnosis When there are many sick kids in a community, but none look undernourished, be sure to look for protein deficiency. Why? • It’s important not to miss the diagnosis. Kwashiorkor has a high fatality rate even with hospitalization • The 1 st symptom to present is often diarrhoea, or oedema • The child may be treated for a gastrointestinal infection while the underlying cause, kwashiorkor, goes undiagnosed • Oedema is an early symptom, and may be mistaken for chubby limbs, so test if nutrition may be compromised Page 48
Tracking protein-energy malnutrition in kids Failure to thrive may be an early warning of flagrant PEM in an individual child or a community. Always investigate the cause • Growth charts give weight for stature / length across age. They provide criteria to estimate severity. Proper use requires training! • Change in position on a chart shows effectiveness of treatment & probability of survival • If many children in a community show up at risk on growth charts, authorities must be alerted to endemic problems Page 49
Early measures required on PEM diagnosis • Treatment is urgent - hospitalization is preferred if available • Delayed physical growth is often restored in catch-up growth when a good diet is provided • Cognitive disabilities may be irreversible if prolonged • Ready-to use foods (RTUF) for PEM have saved many lives • Oral rehydration salt (ORS) therapy is also life-saving when there is accompanying diarrhoea (which is usually the case) Note L Page 50
Early measures required on PEM diagnosis • Both RTUF and ORS can be given at home in a bottle (Wikipedia). World production of ORS is around 500 million sachets / year. Improvisation of ORS is described at http: //rehydrate. org/ors/made-at-home. htm#recipes • Powdered milk protein in boiled water can be very helpful as an emergency measure • Acute fatality rate can be 25% even with prompt treatment Page 51
Iron deficiency affects 500 million globally http: //www. micronutrient. org/English/view. asp? x=579 • Causes: insufficient availability of dietary iron, or increased iron requirements to meet reproductive demands, haemmorhage, parasitic infections (often concurrently) • The result is an increasingly severe anaemia, reduced work productivity → poverty, diminished learning ability, increased susceptibility to infection For more on consequences of iron deficiency, see Note M Page 52
Iron deficiency affects 500 million globally • Iron deficiency is best diagnosed in the preclinical stage, by measurement of transferrin saturation • Females > males due to iron loss at menstruation -- >50% of pregnant women are affected in the developing world – 3 times as many as in developed countries • 25% of men also are deficient in iron in the developing world Page 53
Treatment of iron deficiency: rebuilding iron reserves • Iron tablets are effective within weeks, but non-compliance is common so compliance must be checked • Increase iron intake through combining iron-rich foods with agents that iron absorption (like vitamin C) • Encourage availability and consumption of iron-fortified foods Page 54
Treatment of iron deficiency: rebuilding iron reserves • Weekly / daily supplementation is recommended for vulnerable groups in areas with intractable iron deficiency • Treat causes of diminished iron reserves: haemorrhage, parasites (including malaria), and hemolytic conditions. • Be alert! Iron may be lethal in some inherited anaemias (thalassemias, sickle cell, or Hb M) common in Africa & Asia Page 55
Iron excess - dangerous to some • Those with haemolytic anaemias: (e. g. , thalassaemia – common in people of African or Asian descent). Iron should not be prescribed until the cause of an anaemia is known • Where iron pots are used for cooking or beer: Siderosis: iron deposition in liver, kidney, heart, pancreas organ failure • Children: Parents' iron pills are attractive to kids in developed countries. The most common of fatal childhood poisonings • Those with familial haemochromatosis: This common inherited disease has symptoms similar to siderosis (above) The first sign of this disease is often inoperable liver cancer Note N Page 56
Vitamin A deficiency in public health • Vit. A deficiency is a public health problem in over 70 countries, especially in Africa, SE Asia & the W Pacific where it affects 250 million mostly aged 0 -4 years • Night blindness may predict vitamin A deficiency, with risk of permanent total blindness if it progresses • There is also increased risk of severe illness and death from infections such as diarrhoeal disease and measles • Vitamin A supplements can be beneficial when given as seldom as once a year. Check the latest information at: http: //www. micronutrient. org/english/View. asp? x=577 Page 57
Vitamin A deficiency & perinatal health • Vit. A is crucial for maternal & child survival, supplements in high-risk areas can dramatically decrease maternal mortality* • In pregnant women Vit. A deficiency is seen in the last trimester when demands by unborn child & mother are highest • Partnerships for progress in vitamin A nutrition In 1998 WHO, UNICEF, CIDA, USAID (ia) launched a global initiative in 40 countries that has to date averted 1. 25 million deaths, by giving vitamin A to kids at clinics *This issue is under active investigation. For the status at time of writing see Lancet, Volume 376, Issue 9744, p 873 - 874, 11 September 2010 Page 58
Vitamin A deficiency & perinatal health • Night blindness in pregnant women - an early danger sign • In children, the cost-effective prevention is breast-feeding • Genetically engineered high Vit. A rice crops could help Caution: Vit. A supplements as retinol are controversial. It can be toxic & teratogenic ( birth defects). However, given as carotene, vitamin A supplements are safe, leading only to an orange tinge in skin colour. Page 59
Iodine deficiency disorders • The world’s major cause of preventable brain damage In 1990: 1. 6 billion people were at risk in over 100 countries, mainly in parts of Africa and Asia where soil is iodine-deficient • Close to 40 million children have mental impairment from lack of iodine • As a result of the micronutrient initiative, this number is falling For latest data, see: http: //www. micronutrient. org/english/View. asp? x=578 Page 60
Iodine deficiency disorders • Consequences start before birth and continue afterward – In utero, spontaneous abortion, congenital abnormalities & retarded foetal development – In early childhood and progress toward adolescence iodine deficiency causes cretinism, an irreversible retardation. Impacts home, school, & work – Today we are on the verge of eliminating iron deficiency --- a major public health triumph like getting rid of smallpox & polio Page 61
Toward iodine sufficiency – iodized salt • A cost-effective low-tech therapy, iodized salt costs just $0. 05 person per year • UNICEF, ICCIDD (International Council for Control of IDD), & the salt industry have set up iodization programmes. Globally, 66% of households have access to iodized salt. • As of 2009 the number of at risk countries has been halved! • However, progress has slowed and we are a decade behind promises of the international community. • 54 countries are still affected – efforts must continue Page 62
Nutrition in Global Health Causes, mechanisms, solutions Nutrition is crucial to global health & MDGs 1. Overview of nutrition across humankind 2. Human nutrition fundamentals in global context 3. Top 6 nutrition problems, & their solutions 4. Nutrition across the life cycles of rich & poor 5. Cause & effect in population nutrition 6. Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger Page 63
Nutrition through the life-cycle Page 64
Factors in perinatal nutrition (see also Acute Malnutrition module) • Nutritional health begins in the womb – a healthy outcome to a pregnancy requires that mother be well nourished; good feeding must initiated early • The most common birth defects result from a deficiency of folic acid in the diet of the pregnant mother, Best outcomes require folic acid supplementation before conception! Page 65
Factors in perinatal nutrition (see also Module on Acute Malnutrition) • Delaying clamping the umbilical cord until it stops pulsing iron stores see: www. naturalchildbirth. org/natural/resources/labor 04. htm • Ideally, babies should receive vitamins E & K injections at birth • A baby who’s healthy at birth may experience "failure to thrive" (or "growth faltering") in the first year of life. So …. . • Good infant feeding behaviors must start early. Most importantly, breastfeeding should be initiated within an hour of birth & maintained exclusively for 6 months. • Breastfeeding could prevent 1. 3 million deaths each year http: //www 2. unicef. org/nutrition/index_22657. html • Page 66
Perinatal nutrition requires attention 1 • Malnutrition in pregnancy birth defects & low birth-weight • Failure to thrive is an early danger sign, requiring investigation • Nutrition in infancy to early life impacts physical & cognitive development. It determines immediate & future risks of blindness, thyroid function, bone development, & more • Under-nutrition or deficiencies of many micronutrients can cause failure to thrive“ • Iron, vitamins K and E are of particular importance. Refer to: 1 http: //www. who. int/nutrition/topics/infantfeeding_recommendation/en/index. html Page 67
Malnutrition in early childhood • Children are at special need because they are at the fastestgrowing stage of life. Problems an adult could survive can be lethal to a child • This is the most vulnerable period – a child is developing physically & mentally. Damage can be permanent • Most importantly, they are unable to fend for themselves & depend on others (parents, others) for health & survival • They are the planet’s future. We owe it to them & to ourselves to ensure that they grow well, with a sense that they have reason to invest in the future, in a caring world Page 68
Parenthetically – a personal perspective How easily we see the moral failings of the past. Slavery, the holocausts & genocides, conquests motivated by greed When future generations look amazed at the moral blindness of this generation, what will stand out? Clearly child hunger Where life expectancy is short, toddlers are orphans. In war or famine a region may lack necessities. You can’t blame a child Yet in many rich countries, including the US & Canada, we turn our empty eyes and hands away from those outside our borders A napalmed child turned a nation’s mind to peace. What will it take to open our eyes to children dying of hunger? Page 69
Nutrition through the life cycle - adolescence Adolescence carries risks for both poor & affluent • Adolescent & adult patterns of food consumption & activity massively impact immediate & future health risks • Adolescents are notoriously careless about health. Their eating patterns can lead quickly to obesity or anorexia. Page 70
Nutrition through the life cycle - adolescence Adolescence carries risks for both poor & affluent • Dieting can lead to deficiencies of vit. C, protein, folic acid in a sedentary person. Even if a good mix of foods is consumed, total food intake may be insufficient. • A pattern of healthy eating in adolescence sets a pattern that can promote lifelong health • A foundation for healthy bones is set by exercise, calcium, & vitamin D. After early adult life, bones go slowly downhill Page 71
Nutrition through the life cycle – adult life Nutrition & acute & infectious diseases • Malnutrition depletes immunity leading to increased risk & severity of infections & parasites: AIDS, malaria, etc. • Flagrant deficiencies of specific micronutrients can put at risk the life & health of the mother in pregnancy & lactation • Nutritional anaemias, pellagra, blindness, skin disorders beri, scurvy, etc, can range in severity from mild to fatal Page 72
Adult life - degenerative diseases • In late life, risk of breast, prostatic, & most other cancers are predicted by diet, obesity, inactivity or smoking in adult life • Also heart disease, strokes, osteoporosis, diabetes • Cancers and diabetes are now leading causes of death & disability in low- and middle-income countries (see Lancet, August 13, 2009) • Nearly two-thirds of the world’s 7. 6 million cancerrelated deaths now occur in developing nations. Page 73
Differential nutritional vulnerability of females • Women are much more prone to nutritional anaemias since they need to replace red cells lost in menstruation • Women are the majority of elders, increasingly so in Asia and Africa. Osteoporosis is more common in the elderly • Osteoporosis is a major cause of illness, disability and death. The annual number of hip fractures worldwide will rise from 1. 7 million in 1990 to around 6. 3 million by 2050. Page 74
Differential nutritional vulnerability of females • Women suffer 80% of hip fractures; lifetime risk 30 - 40% compared with 13% for men. • Osteoporosis prevention (exercise, calcium, & vitamin D) must start well before age 30 when bones still respond. • Negative calcium balance in later life is not very responsive to nutritional measures. Page 75
Under- & over-nutrition occur in all cultures • Disparities in income, nutrition & health care increasing between countries & within groups in the same country In addition, in low and middle income countries diseases of overnutrition are increasingly common • Obesity related disorders, including diabetes, are now as important in some lower to middle income countries as in North America and the European Union Page 76
Also, under-nutrition occurs in many rich nations • In rich nations, enormous wealth for some has left others ravaged by health costs, unemployment, foreclosures • Developed countries have marginalized cultural groups. Hunger is common in N & S America, China & E Europe • For example, ~49% of US children (and over 80% of black children) require food-aid at some time during childhood • Scandinavia & few western European countries are almost the only exceptions Page 77
Overnutrition is no longer limited to rich countries Obesity is a growing problem worldwide, particularly among those who lack resources for a wide range of food choices. • All too often, the cheapest foods are high calorie, poor in nutrients, rich in sugar, salt, fat, & trans-fats • The predominant cause of obesity is under-exercising rather than overeating. On average, overweight people eat slightly fewer calories than lean people, but are much less active • Obesity increases risk of many disorders, most notably cardiovascular disease, cancer, adult-onset diabetes. “Prevention is much better than cure”. Page 78
Overnutrition is no longer limited to rich countries • Previously, the poorest were almost immune to diabetes, hypertension, gout, & atherosclerosis & heart disease • No longer. These are growing problems, impacting health worldwide. In the next few slides we’ll consider prevention. • Diabetes has reached epidemic proportions threatening, vision, kidney function, mobility, heart-health & life itself. • A cluster of symptoms, hypertension, hyperlipidemia, and hyperglycemia is sometimes called “metabolic syndrome” • Each of them increases risk of heart disease, and together the risk is greatly amplified. Read on…. . Page 79
Prevention of heart attacks and strokes • Risk factors: hypertension, hyperlipidemias (LDL / “bad” cholesterol), inactivity & diabetes. All correlated with obesity • Smoking is the most life-shortening risk factor of all • These risks can be changed earlier or later, by modification of diet & other life-style changes or medication • In the past 5 years research has established that exercise & a lean body are the most powerful predictors of a long healthy life, and also of clear thinking into old age Page 80
Prevention of heart attacks and strokes • There is no easy solution to obesity. In a typical study: <10% of people dieting, <10% of those exercising, and <15% of those exercising & dieting, lost weight. • However, over 80% of those who underwent stomach stapling or banding lost weight! • Not very encouraging for lifestyle treatment. Many argue that surgery to control weight should be done more often Page 81
Measures to diminish cardiovascular risks Lifestyle measures: have greatest impact in older people! • Increasing consumption of fruit & vegetables by one to two servings can cut cardiovascular risk by 30% • Reduction of blood pressure by 6 mm Hg reduces stroke risk by 40% & heart attack by 15%. Hydrochlorthiazides (diuretics) are inexpensive and effective • Moreover, a 10% reduction in LDL cholesterol reduces the risk of coronary heart disease by 30% Page 82
Measures to diminish cardiovascular risks • Modest cutbacks in saturated fat & salt improve blood pressure & lipids; & diminish risk of cardiovascular disease • Lifestyle measures are, optimally, combined with pharmaceutical intervention • Best practices regarding diabetes & cardiovascular disease are a moving target. Anyone teaching or practicing in this area needs skills in finding evidence-based information in an ocean of misinformation. Page 83
Nutrition in later life and old age • Worldwide, the proportion of people over 60 is increasing. By 2025, the world will have more than 1. 2 billion older persons – two-thirds of them in low income countries • The foundation laid in earlier life determines risk of diabetes, heart disease, hypertension, strokes, osteoporosis, cancer, etc. All these bring special nutritional concerns. • Many of the diseases of late life are diagnosed too late for effective treatment. Prevention at an early age is the goal Page 84
Nutrition in later life and old age • Old age can be cut short by many kinds of malnutrition • Deficiencies of calcium, iron, water, vit. B 12 can severely compromise old age • Loss of taste and smell can render the elderly at risk for food poisoning from spoiled food • Loss of thirst sensitivity in this age group makes dehydration (inadequate water intake) a common cause of confusion, headache, & occasionally kidney stones • Prevention is better than cure, & symptomatic treatments that are effective, are often unavailable to the aged in LMICs Page 85
Nutrition in Global Health Causes, mechanisms, solutions Nutrition is crucial to global health & MDGs 1. 2. 3. 4. Overview of nutrition across humankind Human nutrition fundamentals in global context Top six nutrition problems, & their solutions Nutrition across the life cycles of rich & poor 5. Cause & effect in population nutrition 6. Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger Page 86
Determinants of population nutrition Any broken link can nutritional inequities. (think about how …) Page 87
The mechanisms of hunger – many paths Notice how one path can feedback to affect others As diagrammed by WHO in “Repositioning Nutrition as Central to Development: A Strategy for Large-Scale Action” Page 88
Sub-determinants of nutritional sufficiency Each factor has its own contingencies. Here a few: Economic development depends on agricultural sustainability • irrigation & soil maintenance (crop rotation, contour plowing) • seeds, fertilizers, appropriate insecticides Agricultural productivity depends on good harvests • climatic: drought and floods • drought - and frost-resistant crops • hybrid seeds and related biotechnology • market for any excess crop, non-exploitative trade Page 89
Sub-determinants of nutritional sufficiency Each factor has its own contingencies. Here a few more: Stability includes freedom from disruptive forces • war (revolts, invasion, political upheaval, social disruption) • exploitation from outside – unequal trading practices • corruption externally – multinational corporations offer bribes and rich nations tolerate this because it benefits them • corruption internally – where some developed nations set a poor example e. g. non-transparent procurement policies Note O Page 90
Poverty - greatest cause of malnutrition (hunger, blindness, disease, birth defects, maternal/neonatal death) The causes of poverty are disputed – no one wants to be part of the cause. What we know is…. • Poverty doesn't just happen, it is caused by economic, political, social & geographical circumstances & decisions • Usually these decisions are made outside the groups of people most affected by it! Note P Page 91
Poverty - greatest cause of malnutrition (hunger, blindness, disease, birth defects, maternal/neonatal death) • Old people, women and under-supported children are most likely to be impacted by poverty • Uneven distribution: 2/3 of undernourished people live in Asia • Hunger is growing fastest in Sudan, Rwanda, Burundi, Chad D. R. Congo, Sierra Leone, Zimbabwe, Somalia Page 92
Nutrition in Global Health Nutrition is crucial: Millions more are fed, but Nutrition is crucial 1. Overview of nutrition across humankind 2. Human nutrition fundamentals in global context 3. Top six nutrition problems, & their solutions 4. Nutrition across the life cycles of rich & poor 5. Cause & effect in population nutrition 6. Overview and where we are now Bridge to Part 2, Roadmap to a world without hunger Page 93
Where are we? Considerable hope for the future, with great distress & urgency in the present • Globally, more are now adequately fed than ever before. • Many populations are growing. . . and yet the percentage being fed continues to increase • The MDGs will mostly be mostly met. . . but not on schedule. Page 94
Where are we? Great hope for the future, with great distress & urgency in the present Does that mean we are doing enough? Absolutely not! • Improvements in nutrition are not equally spread: in Africa more are hungry • Most of those born today will live to see hunger shrink to temporary pockets, managed by relief aid • Meanwhile, even as extreme hunger decreases, it’s too slow to stop the needless loss of millions of lives each year Page 95
What has changed? At last it’s clear Disparities are now so great there is almost complete agreement that the plight of the poorest must be addressed The cost of conferring great benefits is a fleabite to the rich. $20 from an individual can save a child’s life and 0. 7% of GDP from the richest nations could, in two decades, wipe out the deadliest disparities
What has changed? At last it’s clear What’s needed was defined in 2001. Amazingly 22 nations signed on to fund 7 MDGs with 60 indicators of success, and to provide the funds! 1 st aim: eradicate extreme poverty & hunger We’ve seen what worked & what didn’t. The MDG projections were accurate, but. . . Page 97
While some well-intended nations. . . honoured their commitments in full, or at a higher level (here we honour northern EU, Luxemburg & Netherlands). . . most provide approximately half the aid that they undertook and are increasing – (here, much of west-central EU). . . a very few provided a third or less & are decreasing – (here we include the nations of N. America & Japan) the consequences are unsurprising…. Page 98
The consequences are unsurprising • Thanks to nations & individuals who put worthwhile goals ahead of strictly national interests, a better nourished world emerges • The majority of nations are now solidly on the development ladder and the number grows each year • Millions die unnecessarily in E and S Asia, & sub-Saharan Africa, and the major cause rests with a few nations Page 99
Nutrition in Global Health Bridge to a roadmap to a world without hunger Why nutrition is crucial to global health & MDGs 1. Overview of nutrition across humankind 2. Human nutrition fundamentals in global context 3. Top six world nutrition problems, & their solutions 4. Nutrition across the life cycle & in rich and poor nations 5. Cause & effect: Determinants in population nutrition 6. Where we are now: Overview Millions more are fed but without urgent action, millions more will starve On to Part 2: Roadmap to a world without hunger Page 100
Roadmap toward a world without hunger We’ve concluded Part I of the nutrition modules with a preliminary assessment of prospects for “eradicating extreme poverty & hunger. ” In Part II we ask “what works and what doesn’t? ” We will… 1. … discuss the confounders & wild cards & elaborate on the range of possible future scenarios 2. … contend that many controversies fail to see that many “competing” approaches are, in fact, complementary 3. . categorize competing viewpoints as evidence- or ideologybased & subject them to the test of science 4. … survey current strategies, assessing their strengths, weaknesses, & applicability to real life problems Page 101
Review your pre-quiz* to confirm that you have advanced your knowledge. As we move now to the future, here is part of the pre-quiz* for the Part II Nutrition module (*Quiz feature pending upgrade of GHEC IT platform) • Does globalization promote nutritional health? For whom? • Is free enterprise good for everyone? If not, for whom? • Are most African leaders dictators? • Does most aid to Africa end up in Swiss bank accounts? • Does food aid do more harm than good? Academics & politicians argue about these questions and what should be done. Does that mean that we don’t know what to do? We will see in Part II that the answers are clear Page 102
Summary: What you’ve learned … • Nutritional health is not equitably distributed worldwide Correcting nutritional inequities is crucial to a viable future • We've reviewed nutritional principles in global context Nutritional health, public health, & economics are inseparable • Worst nutritional risks: unsafe / inadequate water and protein, iron, vitamin A & iodine deficiencies As you reframe this information in your own context , it will help you see: what to look for, what to ask for, & what to do
Applying what you’ve learned • Ranking risks in the life cycle - kids & mothers are top priority Help you set priorities & best practices for risk mitigation • We have seen setbacks, slow progress toward the MDGs. Yet There is substantial agreement about what needs to be done • Reasons for hope: Fortunes given away, crazy ideas, loans to the poorest repaid, workable strategies toward a world without hunger & clear-sighted agents of change We return to our task with renewed clarity & energy
References and resources • See the notes for much additional information about resources, books, compilations of government information, and toolkits for finding more information. Note Q Page 105
Case study analysis of progress • See Note P for a Case study Analysis of Progress in a cluster of Millennium Villages. The MDVs are described in GHEC’s module #2, “Millennium Village Project: A Demonstration of Reaching the MDGs” Note P Page 106
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Acknowledgments I single out a few of many whose insights, persistence, and courage dispelled the pessimism I felt when I began this task. Jeffrey Sachs, Yunus Muhammad, Raj Patel, Kumi Naidoo, Paul Collier, Howard Zinn, Vandana Shiva, & Frances Moore Lappé Also the hundreds of passionate students, practitioners, and researchers at meetings of the Canadian Consortium of Global Health who passed on to me their energy & vision. Pre-eminent among those who encouraged me are Vic Neufeld & Tom Hall Page 108
End of module Please refer to the supplementary contents for more information about this module. [Reserved for GHEC notes]
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