Table 3. Greenhouse gas emissions (GT CO2e/yr) using FAO data, assuming universal adoption of the Harvard Healthy Eating Plate (HHEP) nutritional guidelines for 7 billion people (today) and 9.8 billion people (projected for 2050).
Percentage changes from the current values are given for both alternative scenarios in parentheses.
| Food groups | Without adoption of HHEP (Existing diet) | With adoption of HHEP diet | ||||
|---|---|---|---|---|---|---|
| Existing ratio of protein from livestock and plants | Protein from plants only | |||||
| For 7 billion (FAO data today) | For 9.8 billion (2050) | For 7 billion (today) | For 9.8 billion (2050) | For 7 billion (today) | For 9.8 billion (2050) | |
| Whole grains | 0.88 | 1.24 | 0.54 (-39%) |
0.76 (-14%) |
0.54 (-39%) |
0.75 (-15%) |
| Fruits & Vegetables | 0.32 | 0.44 | 0.58 (+81%) |
0.82 (+156%) |
0.58 (+81%) |
0.81 (+153%) |
| Oils & Fat | 0.07 | 0.10 | 0.03 (-57%) |
0.04 (-43%) |
0.03 (-57%) |
0.04 (-43%) |
| Livestock Protein | 2.90 | 4.06 | 5.85 (+102%) |
8.19 (+182%) |
0 | 0 |
| Fish Protein | 0.38 | 0.53 | 0.34 (-11%) |
0.47 (+24%) |
0 | 0 |
| Plant Protein | 0.12 | 0.17 | 0.22 (+83%) |
0.30 (+150%) |
1.58 (1217%) |
2.21 (1742%) |
| Milk/dairy | 0.64 | 0.89 | 0.59 (-8%) |
0.83 (+30%) |
0.59 (-8%) |
0.84 (+31%) |
| Sugar | 0.04 | 0.05 | 0 | 0 | 0 | 0 |
| GHGs Total | 5.64* |
7.89** (+40%) |
8.39*** (+49%) |
11.74**** (+108%) |
3.56*** (-37%) |
4.99**** (-12%) |
*Includes 0.29 GT of CO2e/y for transportation and upstream energy use
**Includes 0.41 GT of CO2e/y of for transportation and upstream energy use
*** Includes 0.24 GT of CO2e/y for transportation and upstream energy use
**** Includes 0.34 GT of CO2e/y for transportation and upstream energy use