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Nutrition and food security
some principles (cont)
DRAFT
Nutrient Size (req/day) Role, reason Deficiencies
1. CHOs, Fats, N(protein: AAs)
Up to 500 g Energy, buildingblocks – structure,metabolism
Diverse clin signs. Not clearly linked torole.
2. Na, K, Ca. Up to 5 g Solute (seawater),homeostasis
Not really seen
3. Phosphate, Cl Up to 5 g As 2 Not really seen
4. Vit C Up to 0.1 g, 100mg
Antioxidant in mostcells; enzyme lostin evolution
Scurvy. Not clearlyrelated to function.
5. B-vits Up to 50 mg Co-factors inmetabolism(opportunisticevolution)
Specific signs, notclearly related tofunction
6. Essential Aasand FAs
... g Structure,metabolism; like B-vits
Some specificsigns, but not wellknown nor clearlyrelated to function
7. Metals: Fe, Zn,Cu, Mg, Mn, ...
1 – 10 mg(available)
a) Fe: carry O2
b) active sites ofenzymes (incl. Fe)c) other (e.g.cognitive)
a) anemia andcorrelatesb) non-specific orno signs (e.g. Zn)c) research area
8. I, vit D mcg Hormones, controlof homeostasis,growth, etc.
Specific signs(IDDs, rickets)when severe.
9. Vit A mcg a) visual cycleb) membranes
Specific signswhen severe; mild,mortality effect
plus almost all affect immune system
Energy needs of population depend on:
• Resting metabolic needs (BMR)
• Activity: > 1.5 BMR
• Demographic composition – ( includes pregnancy and lactation)
• Temperature
• E.g. emergencies 2100 kcals; usually around 2200 kcals; see RDAs
• Energy needs: about 2200 kcals/hd/day, averaged over popn
• Protein: about 10% of energy should be from protein.
• CHO: 3.5-4.0 kcals/g
• Protein: 4.0 kcals/g
• Fat: 9.0 kcals/g
Nutrient types and deficiencies
Type I - reduced tissue concentration and specific clinical signs
Type II - reduced growth rate and non-specific signs
TYPE I
growth continues in early stages specific clinical signs develop tissue concentration drops with deficiency body stores exist concentrated in particular tissues specific enzymes affected not usuallv anorexic tissue concentration independent of the other type I nutrients tissue concentration maintained in different metabolic states food sources very variable diagnosed by biochemical tests anthropometric abnormality only appears late in the deficiency .
TYPE I nutrients Iron copper manganese iodine selenium calcium fluorine thiamine riboflavine pyridoxine nicotinic acid cobalamin folate ascorbic acid vitamin A (retinol) vitamin E (tocopherol) vitamin D vitamin K
Nutrient types and deficiencies
Source: M Golden
TYPE II nutrients potassium sodium magnesium zinc phosphorus protein
nitrogen carbon skeletons of essential amino acids threonine lysine sulphur [oxygen] [water]
[energy]
TYPE II
growth failure first response no specific clinical signs tissue concentration maintained with deficiency no body store of these nutrients not in any particular tissue general effect on metabolism anorexia common response tissue concentration dependent upon all the other type II nutrients tissue concentration may change (drop) with metabolic state ratio in foods not very variable do not give biochemical abnormalities diagnosed by anthropometric abnormality
Nutrient types and deficiencies
Source: M Golden
TABLE 1 PERCEPTIONS AND RELATIVE PRIORITIES OF INTERVENTIONS Problem Presentation Intervention Vitamin A deficiency Striking: blindness,
increased child and maternal mortality risk
Easy in children: infrequent high dose capsules
Iodine deficiency Striking: cretinism, dwarfs, goitre
Easy: iodized salt
Iron deficiency Subtle: anemia, reduced cognitive development
Difficult: e.g. frequent supplementation
General malnutrition -- growth failure
Subtle: smaller children Difficult: community-based programs
General malnutrition -- starvation in emergencies
Striking: emaciated and dying children and adults
Easy (in principle): emergency food aid and other assistance
What would it take to eliminate malnutrition?
Economic growth, jobs, improved income distribution
Education, especially for women Reduced fertility, family planning Nutrition in health services,
schools Community-based programs
including nutrition
Nutrition influence
Low Higher
Household food security.• Except in emergencies (and even then) interventions to improve food security
are pretty much the same as those to reduce poverty.
• Relevant actions:– Macroeconomic adjustment
– Employment policies
– Employment provision
– Agricultural policies
– Food prices and subsidies, public distribution• General subsidies
• Targeted
• Rations and quotas
• Food stamps and coupons
See: ‘nutrition-relevant actions’ www.unsystem.org/scn
Measure food security and hunger:
• FPI/CPI
• Income/exp surveys
• Food cons surveys (incl 24 hr recall)
• Food perception q’aires
• Anthropometry ?See FIVIMS meeting: http://www.fivims.net/documents/ISS/ISS_e/ISS_exesum.pdf
ISSUES IN COMPLEMENTARY FEEDING
Weanling’s dilemma
Time for caring – feeding frequency
Quality
Timing
Bulk
Cleanliness
... and continue breastfeeding
Complementary foods
Ideal pattern of infant feeding
6 mo
12 mo
24 mo
100%
50%
0%
Breast fed only
Breast fed and complementary foods
Interventions in relation to the life cycle.
Antenatal care Birth attendance
Breastfeeding – initiation, exclusive to 4-6 months,
continue into second year
Child feeding practices (weaning)
Immunization
Water/sanitation/food security
Household food security.• Except in emergencies (and even then) interventions to improve food security
are pretty much the same as those to reduce poverty.
• Relevant actions:– Macroeconomic adjustment
– Employment policies
– Employment provision
– Agricultural policies
– Food prices and subsidies, public distribution• General subsidies
• Targeted
• Rations and quotas
• Food stamps and coupons
See: ‘nutrition-relevant actions’ www.unsystem.org/scn
• Community-based and service delivery (facility-based) programs
• Vertical micronutrient programs
• Nutrition in health services and schools
• Contextual and supporting policies.
PROGRAM DESIGN FACTORS
Coverage — % of population participating
Examples: % children immunized (of appropriate age) % pregnant women with ANC
Targetting — preferentially including a target group
by vulnerable group (often biological, e.g. by age, pregnancy),usually involving selection of individuals
by administrative or geographic area by s-e status (uncommon in practice — e.g. food stamps by
means testing)
Assess by estimating prevalence in participants: prev in overall population(should be > 1).Note: principle should be to only target those who can respond ...
Intensity — resources applied per participating population
Examples: $/head/year personnel/population/year — e.g. mobilizers/family supervision ratios — facilitators/mobilizer; nurses/doctor other resources: hospital beds/head; nurses/head;
supplies/head; etc.
Program content
depends on causes of the problem open to intervention depends on interaction with contextual factors — e.g. literacy/
behaviour change adequate intensity needed before impact for many actions;
probably non-linear.
PREQUISITES
Decide on: objectives (incl for whom) program activities that could reach objectives indicators of outcome (i.e. of objectives) and process (i.e.
of activities) coverage, intensity and targetting required to actually
meet objectives (see next) organization, institutions, finance ... iterate and negotiate until it makes sense (or doesn’t —
that must be decided too).
It’s not in principle more complicated than that; the most difficult partis deciding the content. Most planning protocols come down to this. Some try to impose a cookbook approach (like the ‘log frame’) —they don’t usually work. Better by far is to build the local capacity tofigure these things out ... help to get started ... fund crucial elements.
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