Lindsay Allen, USDA "Agricultural Research and Nutrition: What we know and what we don't know"

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Science Forum 2013 (www.scienceforum13.org)
Keynote plenary session
Lindsay Allen, main respondent

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Lindsay Allen, USDA "Agricultural Research and Nutrition: What we know and what we don't know"

  1. 1. Agricultural research and nutrition: what we know and don’t know Lindsay H. Allen USDA, ARS Western Human Nutrition Research Center Davis, CA
  2. 2. Masset: nutrition outcomes • Change in intake – – in 13/19 was ↑ intake of targeted food, – but few measures of total daily nutrient intake. – diet diversity is poor measure – need quantity. • Anthropometry – very little effect of most foods; need 5000 to detect 10% ↓ in stunting or underweight (i.e. not sensitive outcome). True for supplements. • Nutritional status – only effect on serum retinol (4/9 studies). – no effect iron intake; Zn not measurable. – there are few MN-rich foods.
  3. 3. MMN: effect sizes for change in growth (by age) -1 -0.5 0 0.5 1 Overall Daily Weekly Daily, non-placebo control Weekly, non-placebo control Supp All Food Olney, Pearson & Allen, 2009
  4. 4. Animal source foods do improve child growth and development!
  5. 5. Milk vs. meat intervention trial in schoolers, Embu, Kenya (n=554, 2 years) 30% stunting, famines, low ASF, 30-90% prevalence various deficiencies
  6. 6. Outcomes in ASF intervention groups vs. controls • Meat supplementation (60-80 g/d) improved: cognitive performance (Raven’s, math) school test scores physical activity initiative and leadership behaviors arm muscle mass (due to higher activity?) • Milk supplementation (1 cup/d) improved: linear growth of stunted children • Milk or meat supplementation improved: vitamin B-12 status
  7. 7. Meta-analysis of dairy products and physical stature (de Beer et al., 2012) 12 studies, n ≅ 3500. 7 countries/regions (including wealthier). Mix RCTs (recent) + observational. +750 mL milk →→→→ 0.4 cm ↑↑↑↑ height.
  8. 8. The agricultural community’s approach to improving nutrition Biofortification ≈5 key cereal, legume, root crops: to reduce hunger, for income, biofuels, etc. 2005 2010 2015 ASF Small holders
  9. 9. The nutrition community’s approach? “Complementary” micronutrient interventions Diet quality improvement Fortification 2-5 MN Supplementation MN powders 2005 2010 2015 Peanut-based MN
  10. 10. Current micronutrient policies and strategies Preg- nancy Lact- ation 0-6 mo 6 mo-5 y Women, children Fe + folic acid Breast milk Vit. A capsules, Fe. “Nutrient dense HH foods” MMN (powders, lipid- based, fortified complementary food)* Fe if anemic Staples fortified with Fe, A, Zn, folic acid, B12 Biofortification with A, Fe, Zn* * Not official WHO policy
  11. 11. Coordinate agriculture, fortification and supplementation to meet nutrient needs Goal: <5 % population group <EAR and >UL, key nutrients. Status normalized. Food intake (n=100/group, 2 day subsample) Nutrients % people <EAR & >UL, each nutrient 1. Plant sources Gaps 2. Animal sources Traditional, local Regional/new Biofortification Traditional, local New A, Fe, Zn B12, B2 Ca, D, E Energy A, C, fol (Fe, Zn) 3. Fortification, supplements
  12. 12. Planning agriculture for nutritional needs 1. The ENAM project in Ghana Enhancing child Nutrition through Animal source food Management WID Univ. Ghana Iowa State McGill 2 Intervention + 2 Control communities per zone
  13. 13. Phase 1: developed problem model for key constraints on ASF (interviews, focus groups, workshops). Income Marketing linkages Processing and storage Feeding skills and nutrition knowledge Household food allocation Cultural beliefs and attitudes ASF Availability Accessibility Utilization Financial services Seasonality Pests and diseases Caregiver empowerment Household size Number of extension field staff
  14. 14. Nutrition education Microcredit loans & savings $50 (fish smoking and sales, poultry and eggs, sale of yams and cooked foods) Entrepreneurship education ENAM phase 2: Interventions to improve food security and use of ASF for children Weekly meetings
  15. 15. Results In intervention vs control or non-participant households: • 50% reduction in food insecurity previous month. • 0.12 Z increase in height, 0.26 Z increase in weight. • Higher intake of protein (30%), calcium (50%), zinc (30%), iron (20%).
  16. 16. Example 2 Homestead production in Bangladesh “Diversifying into healthy diets” Iannotti et al. 2010 • Helen Keller International • Small-scale home gardens with MN-rich plants → small livestock, nutrition education. • Scale-up implementation by >70 local NGOs, government. – Tripled veg. production, increased income – ↑ consumption of MN-rich foods – ↑ food security for 5 million, very sustainable
  17. 17. Additions: what we do don’t know • What strategies best to improve DQ of poor? • How and why diets are changing with and across HH, countries? How to influence this. • How effective longer-term ag. interventions are for improving nutrient status and growth vs. CD risk. • Unintended effects on diet (food sold & purchased; earlier breastfeeding), BMI, water quality, food security and safety. • How best to integrate MN interventions.
  18. 18. Additions: what we do know • Few interventions ↑ growth directly; ASF, MILK. • Growth is an insensitive outcome. • Anemia also insensitive status outcome (use breast milk MN? Serum B12? Match to intervention. • Ag. should impact whole household, not focus on only pregnancy, young children. • Ag. interventions should be planned to meet nutrient gaps. If not, little effect will be seen. • Impact on whole diet should be well measured, for several HH members. • IMPORTANT: Education, behavior change, micro- credit, women, local practices…..
  19. 19. Thank you
  20. 20. Animal and plant foods provide different nutrients (relative amount/100g) Cereal Leg- umes Veg Fruit MFP Eggs Dairy Prot + ++ + +++ ++ ++ A (++) (++) + +++ ++ Fe (+) + (soy) +++ + Zn (+) + +++ + + B12 ++ ++ +++ Ribo + (+) (+) ++ +++ Fol +++ (++) (++) + +++ D + +
  21. 21. -10 0 10 20 30 40 Meat* Milk Energy Control Changeintotalexamscore Change in end of term test scores MEAT group improved most *

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