1. Factors Affecting Demand for Food
Text extracted from
The World Food Problem
Leathers & Foster, 2004

2. Age Structure Population Pyramids indicate age structure
Developing countries have much higher percentage of young people
Developed countries have even distribution of age groups

3. Momentum Changes in age structure affect population for decades
Example: Baby Boom
If a developing country achieves replacement fertility rates for adults
Population growth continues for decades
Because there are more children
Baby boom age pyramid

4. Dependency Ratios Ratio of dependents to working adults
Burden of dependent children per adult greater in developing country
Developed nation ex:
0.21 children/adult
Developing nation ex:
.77 chlidren/adult

5. Age Structure determines future calorie needs
Calorie needs are different at different ages
Age structure allows prediction of future calorie needs
as current population grows up
Need for food can grow faster than the population
if more adults than children
Adults require more food

6. Other factors affecting future food needs
Number of Pregnant women
Amount of physical activity
Height of population
indicates nutrition level
Population + demand/person + more meat
Huge synergistic effect
Sierra Leone 8 yr old

7. More Meat As incomes rise, people eat more meat, less cereals
Meat production requires plant calories
Average 6:1 conversion ratio
Developing countries eat 4,224 Calories from plants
2,255 directly from plants
Plus 315 meat calories (12.5%)
Requires 1,969 plant calories to produce meat

8. More Meat If people in developing countries ate 15% meat
Would increase total plant calories required to 4,591/person
Equivalent increase in demand to 8.7% increase in population

9. More Meat
If people in developing nations ate amount of meat eaten in developed nations (27% calories)
Would require 6,200 plant-derived calories
47% increase

10. Optimistic Future Scenario: Next 50 yrs
Per capita income increases
Population growth of 50%
Fertility declines
Food supplies keep pace with demand
Life expectancy increases
Average height increases
Age structure changes toward fewer children
Food demand grows by 101%
Morocco: middle income country

11. Same impact if pessimistic future
Self-Correction on impact with lower quality of life:
If prosperity declines
Food supply doesn’t keep up with demand
Population grows more rapidly
Less decline in fertility rates
But need less food because
Age structure: more children
Average height: less change
Calories per capita low
Dietary diversification small
Impact: 98% growth in food demand
Sierra Leone