WHAT IS PUBLIC HEALTH NUTRITION?

• Problems related to inadequate quantity and quality ofthe habitual diet

• Problems related to excessive intake of quantity of thehabitual diet

• Food-related problems that affect the health and functionof a large percent of the general population or specificages, gender, geographic, socio-cultural groups ordevelopmental/physiologic stages

• Problems prevented or ameliorated by identification ofrisk factors and early detection by screening whenfeasible, in contrast to only specific nutrient treatment

INADEQUACY

• Low quantity of food for requirements

• Low density of specific nutrients

• Poor absorption of a given nutrient or nutrients

- presence of other constituents of the food such as highfiber and phytate

- competition of nutrients (i.e., iron with zinc)

• Infection and intestinal parasites

• Malabsorption due to enzyme deficiencies, structuraldamage to intestinal surfaces

• Drug-nutrient interactions

EXCESSIVE INTAKE OF FOOD AND NUTRIENTS

• Food intake above physiological needs fornormal function and growth in children

• Intake of vitamins, minerals and othermicronutrients far in excess of nutritional needs

EXAMPLES:

Fast food addiction and calorie-dense snacks

Megadoses of vitamins and othermicronutrients and “natural supplements”

COMMUNITY-LEVEL NUTRITION EQUATIONSHOW TRANSPARENCY of CNL

Will focus on interconnected area of the world globaloutlook -- the Nutrition Transition

Developing countries with predominately poor people plus an increasingly wealthy, middle-class, urbanized population with adaption of physical activity, stress, etc.), over-nutrition with high-energy diets, alcohol, high intake of refined sugars, etc.

AND

Industrialized, wealthy countries with growing disadvantaged populations with growing food security, income and hunger and malnutrition

MISCELLANEOUS FACTORS IN THE ETIOLOGY OF UNDERNUTRITONMISCELLANEOUS FACTORS IN THE ETIOLOGY OF UNDERNUTRITONGeographicoGeographico--climateclimate Unproductive soilUnproductive soil

Climate (high temperature, extremes of rainfall)Climate (high temperature, extremes of rainfall)EducationalEducational Too few schools (illiteracy)Too few schools (illiteracy)SocialSocial Illegitimacy; family instabilityIllegitimacy; family instability

Absence of family planning (children too Absence of family planning (children too cIoselycIosely spaced; population pressure)spaced; population pressure)Poor communications (food distribution)Poor communications (food distribution)AlcoholismAlcoholism

EconomicEconomic National poverty (low gross national product)National poverty (low gross national product)Family poverty (low per capita income)Family poverty (low per capita income)Low level of industrializationLow level of industrialization

AgronomicAgronomic OldOld--fashioned methods of agriculturefashioned methods of agricultureInadequate protein production (animal and Inadequate protein production (animal and vegstablevegstable))Concentration on inedible cash cropsConcentration on inedible cash cropsPoor food storage. preservation arid marketingPoor food storage. preservation arid marketing

MedicalMedical High prevalence of conditioning infections measles, diarrhea, tuHigh prevalence of conditioning infections measles, diarrhea, tuberculosis,berculosis,whooping cough. Malaria, intestinal parasites)whooping cough. Malaria, intestinal parasites)

SanitationSanitation Unclean, inadequate water supplyUnclean, inadequate water supplyDefective disposal of excrete and rubbishDefective disposal of excrete and rubbish

CulturalCultural Faulty feeding habits of young childrenFaulty feeding habits of young childrenRecent urbanization (changing habits)Recent urbanization (changing habits)Limited culinary facilitiesLimited culinary facilitiesInequitable intraInequitable intra--familial food distributionfamilial food distributionOverwork by women (limited time for food preparation for childreOverwork by women (limited time for food preparation for children)n)Sudden weaning (psychological trauma)Sudden weaning (psychological trauma)

INTRODUCTION

Political-cultural Geographic-climatic

Community Socioeconomic Food Aspects of healthnutrition factors considerations (contributorylevel* (economic, infections,

education) environmentalhygiene, health-related services)

Community nutrition level (CNL) ‘equation’*Especially vulnerable groups

PRINCIPAL PROBLEMS IN THE SO-CALLED DEVELOPING COUNTRIES OR THE “EMERGING NATIONS”

(and to a lesser degree, in the industrialized nations)

The principal public health nutrition problems

Maternal malnutrition with:

• Poor nutrition in preconception period

• Maternal depletion, poor pregnancy weight gain, and depletion of meagernutrient stores (fat and muscle mass, iron, calcium, zinc, etc.)

• Maternal anemia, small pelvic outlet from earlier rickets, or protein energymalnutrition

• Eat down to have small baby for easier delivery

• Low birth weight, small for dates (i.e., low BW term newborns (high mortality,CNS damage, poor resistance to infection, risk for adult CV and diabetes(Barker’s Hypotheses))

• Breast milk may be deficient in vitamins (B12 ,folate, and A ,for example) andquantity if severely malnourished

MATERNAL DEPLETION

Leads to poor nutrition status, decreased longevity

Aftermath of:

• Continuous period of closely spaced pregnancies interspersed

• Near continuous lactation

• Child-bearing starting in adolescence or young adulthood

• Hard physical work

• Poor diet quality and quantity (eating down, cultural prohibitions)

• Condition in pre-conception or entry to pregnancy/lactation with poorbody nutritional stores

Nutrients:

Macronutrients — poor fat stores and lean body massMicronutrients — poor stores of iron, calcium, zinc, vitamin A & B12,

folate, iodine, thiamine

INFANT FEEDING

Exclusive breast feeding (EBF) for first six months (those not EBF have double the infant mortality rate as bottle-fed infants in developing countries)

Breast milk is sterile, multiple anti-infective mechanisms, nutrients tailored to needs and developmental stage of infant, promotes brain development, growth-stimulating factors of digestive tract, psychological benefits for maternal infant pair, few safe alternatives, enhances child spacing (called “lactational ammenorrheä (suppresses ovulation —but imperfectly))

WEANING CHALLENGE – FEEDING THE TODDLER

NEED TO ADD SOLID FOODS TO SUPPLY MORE CALORIES , PROTEIN, IRON, AND OTHER MICRONUTRIENTS (CHILD OUTGROWING THE MILK SUPPLY)

Continue breast feeding until 2+ years child; growing rapidly

Need for energy-dense food (small stomachs!) with high-quality protein, energy, vitamins, minerals, trace elements (iron, zinc,iodine, calcium, vitamins A,C ,B,D, esp. B12)

Above supplied by local beans, cereals, dairy products, and needfor modest amounts of animal foods; i.e., meat, fish

For micronutrients, green and orange plant foods and fruits for vitamins C and A

NOTE: Death rates around weaning time 30-50-fold higher in developing countries than in rich nations, due to combination ofmalnutrition and infection

SCHOOL-AGE-TO-ADULT PROBLEMS

Chronic energy insufficiency

Late onset of puberty

Stunting as adults

Nutritional anemias complicated by other anemias

Iodine deficiency in some areas

Other micron nutrient deficiencies

Calcium deficiency, with osteoporosis in older people (calcium depletion) and osteomalacia (adult rickets)

Fluorosis in some areas

Ben Ben (thiamine deficiency)

Functional outcomes: poor school performance and attention; decreased physical activity; decreased work capacity; decreased cognitive function; overall diminishment of social and economic development

MAIN DEFICIENCY SYNDROMES AND CONDITIONSPROTEIN-ENERGY MALNUTRITION, from mild to severe

Severe states:

Kwashiorkor (protein deficiency)

Marasmus (total energy depletion)

Both are seen in young children (toddlers) and adults

Often seen in combination

KWASHIORKOR, meaning “displaced child”, occurs right after weaning or precipitated by infection (often measles, HIV, pneumonia, etc.)

•Child edematous with low serum albumen

•Decreased immune function - high infection complications

•Child lethargic, apathetic, electrolyte and hormonal imbalances

•High case fatality

•Treatment is high protein diet and treat infection if present.

•Takes two weeks and full recovery

MARASMUS

•Total starvation “skin and bones appearance”•The child is ravenous•Often ravenous and very irritable and hungry•Also infection risk•Chronic serious infections such as Tbc; HIV can contribute to marasmus•Early weaning under six months, with poor substitute causes marasmus•Recovery takes two months +•Treatment is high-energy-dense complete diet•Cognitive impairment if early in life

Stunting:

Prevalence 40-60% of childrenPoor lifelong history of energy, undernutrition, plus zinc deficiency and, at times, iodine deficiency

Functional outcomes:

Early onset - deceased cognitive function; decreased physical work capacity and productivityUsed as an economic indicator

LEADING MICRONUTRIENT DEFICIENCIES (HIDDEN MALNUTRITION IN MILD FORMS)

• Widespread globally

• Functional disabilities

• High societal/economic cost if not prevented and treated

Approaches to control:

• Nutrition education

• Food-based as for iron, zinc. vitamins A and B12, calcium needfor improved household agriculture

• Food fortification where feasible, and people in market economy,or treated water for iodine deficiency

• Pill or capsule distribution (single MN or multiple MNs) (can beproblematic)

• Appropriate food technologies: germination, fermentation,soaking, malting, and solar drying of seasonal fruits andvegetables and meat/fish

NUTRITIONAL RICKETS - DUE TO VITAMIN D AND/OR VITAMIN DEFICIENCY

• Global problem —once very prevalent in USA industrial cities• Present in refugees in large crowded cities in UK and USA• Seen in Africa despite sun - low calcium diet once weaned• At-risk groups are vegetarian, wearing occlusive clothing, not in

sunlight (Moslem women in particular and their infants)

Problems:

• Skeletal deformities of all pressure-bearing long bones• Chest deformities-interferes with chest and lung expansion, with

increased pneumonia, poor bony calcification, and permanentdeformities — bowing, short. In women, this is a serious hazardin pregnancy/delivery, as the pelvis is misshapen with small birthoutlet

• Adults —poor physical work performance if skeletal deformitiessevere

Approach:

Vitamin D, calcium, exposure to sunlight

SPECIFIC MICRONUTRIENT DEFICIENCY DISEASES

Iodine deficiency disease:•Geographic distribution — far from the ocean, in mountains wherewater is from melted snow and ice, river deltas, no ocean products

• Pregnancy: increased wastage, severely retard affected child born(cretin), with irreversible mental and physical retardation

• Goiter common• In lesser forms and older children and adults, mentally dull, short,

poor ability to work and earn• Huge waste of human resources - where treated economic

development follows

Approaches to elimination:• Government legislation to iodize all salt• Hard-to-reach populations, iodine drops in drinking water or in

irrigation water• Iodine in oil by mouth or by injection every 1-3 yrs.

Vitamin A deficiency:Lack of intake of vitamin A-containing fruits and vegetables, milk, and organ meatsBlindness leading global result

World map to show areas of recent or continuing iodine deficiency. Many other countries, particularly in Africa and the Middle East, probably have iodine deficiency but have not yet been surveyed

VITAMIN A DEFICIENCY• Long known to be associated with blindness and signs of “toad

skin” (ophthalmologist Sommers noted that in populations witheye signs of VAD, the children had very high levels of mortalityand morbidity)

• Eye signs were dryness, clouding, then rapid corneal clouding, andliquifaction and extrusion of lens

• Increased deaths from infection; especially pneumonia,diarrhea, measles

• Noted in VAD: body barriers to infection damaged (i.e., skin, allmucous membranes, eye covering); immune function impaired

Approaches:

• Nutrition education, cultivation of vitamin A-rich fruits andvegetables (sweet potato, carrots, tomatoes, green leafyvegetables)

• Food fortification

• Pharmaceuticals: high-dose vitamin A capsule distribution tochildren under five years of age and nursing mothers every sixmonths, low doses to pregnant women

IRON DEFICIENCY

Most prevalent deficiency globally, next to energy (calories)

Many functional impairments:

• Cognitive function, activity and attention - may not be completelyreversible if severe and early in life

• Poor work capacity and performance (iron in muscle (myoglobin)

• Impaired immune function

• Anemia - mild to severe, with poor oxygenation of tissues; latemanifestation

• Neurotransmitters may be impaired

Approaches:

• Food-based for prevention, fortification, and intake of iron-rich foods

• Prophylactic iron in high-risk groups (pregnancy)

• Iron therapy in anemic populations; i.e., young children and pregnancy

• Eliminate hookworm and other parasites (schistosomiasis)

ZINC DEFICIENCY• Widespread globally

• Hard to assess by usual means

• Low absorption from plant-based diets (fiber and phytate block absorbtion)

• Vital for skeletal growth

• Key role in protein synthesis

• Fetal growth

• Key role in immune system: anti-infective, wound healing

• Role in infant child activity and cognitive development

Approach:

• If suspicious, treat

• Food-based: household use of animal foods (especially any kind of meat)

• Germination, soaking, fermenting to reduce phytate in foods, which reducesabsorption

• There are some pharmaceutical trials - limited coverage

VITAMIN B12 DEFICIENCY

• Seen in vegetarians

• Key role in brain and CNS development

• Key role in red blood cell formation

• Role in immune function

• Recently found to play a role in cognitive function in children

• Low breast milk B12 is of risk to an infant

Approach: Promote animal source foods in diet milk and or meat