Overview
This lecture reviews key aspects of global food supply: trends in calorie, protein, and fat availability, their links to nutrition and prosperity, regional disparities, and indicators of undernourishment.
Caloric Supply and Trends
- Caloric supply measures the average daily calories available per person, a core food security metric.
- Since 1961, global per capita calorie supply has steadily increased, especially in Asia and Africa.
- Global trends show convergence, with poorer regions catching up in calorie supply.
- Caloric supply figures represent food available at retail, not actual intake (does not account for waste).
Regional and Historical Variations
- FAO provides the main dataset for international food supply statistics, dating back to 1961.
- Early modernized countries like France and England saw dramatic increases in food supply post-industrialization, eliminating major famines.
Measuring Minimum Needs: MDER
- Minimum Dietary Energy Requirement (MDER) is the minimum calories needed for healthy weight.
- MDER varies by age, gender, and activity, affecting undernourishment assessments across countries.
- A population is ‘undernourished’ if caloric intake stays below its average MDER over time.
Inequality in Caloric Supply
- Within-country disparities measured using the coefficient of variation for calorie intake.
- A higher coefficient (closer to 1) means greater dietary inequality; Sub-Saharan Africa has high values.
Macronutrients: Protein and Fat Supply
- Food security also depends on protein and fat intake, not just calories.
- Global per capita protein supply rose by about one-third since 1961, mainly in developing regions.
- Protein disparity between regions is higher than calorie disparity; North America and Europe have much higher per capita protein supply.
- Protein quality differs: animal-based proteins are 'complete', while most plant-based are not.
- Global fat supply more than doubled since 1961, with the largest regional differences among macronutrients.
- Fat supply increases have slowed in high-income regions recently.
Food Supply and Economic Prosperity
- Strong correlation exists between food supply (calories, protein, fat) and GDP per capita.
- As countries grow richer, food supply increases but tends to plateau or decline in high-income nations.
Food Supply and Undernourishment
- Countries with low per capita calorie supply have higher undernourishment rates.
- Increasing caloric availability leads to decreased undernourishment prevalence.
Key Terms & Definitions
- Caloric Supply — average daily calories available per person in a population.
- Minimum Dietary Energy Requirement (MDER) — minimum daily calories required for health, varying by demographic.
- Coefficient of Variation — statistical measure of calorie intake inequality within a population.
- Macronutrients — nutrients consumed in large amounts: protein, fat, carbohydrates.
- Undernourishment — persistent caloric intake below MDER.
Action Items / Next Steps
- Review assigned readings on macronutrients and food security.
- Explore FAO data and interactive maps for your region.
- Prepare to discuss trends in undernourishment and food supply for next class.