Try not to eat fewer calories than what we recommend, and don't forget to track what you drink. Consider all this as a general guideline, not something written in stone. You can adjust the plan to your individual needs and food preferences.
Lentils and beans (These eco-heroes are delicious and nutritious, and replacing beef with lentils and beans could get us up to 74% closer to meeting our carbon emissions) 
Local and seasonal fruits and veggies (These have a particularly low carbon footprint, and buying local and seasonal reduces processing, packaging, transportation, and food spoilage.)
Whole grains, including pasta, brown rice, and wheat (Lots of health benefits and less processing and energy requirements environmentally, which lowers our carbon footprint.)
Nuts and seeds (The most eco-friendly include peanuts, hazelnuts, sunflower seeds, watermelon seeds, and pumpkin seeds - great protein sources with a lower carbon footprint.)
Chicken (Meat production, particularly beef, requires more land and water, and has higher carbon emissions. Swapping beef for chicken can decrease your carbon footprint)
Tips on what to avoid:
Beef and lamb. Consider limiting or eliminating as they are primary contributors to environmental damage. In fact, beef, mutton, and milk production contribute 80% of total greenhouse gas emissions among livestock. 
Palm oil. Contributes to deforestation, soil erosion and depletion, natural habitat destruction, and higher carbon emissions.
Farmed fish. Require more wild fish consumption than actual fish production. Their feces contribute to water pollution, while the crowding of fish can breed bacteria and other diseases.
Coffee. Increased demand has resulted in a production that contributes to deforestation, heavy water usage, and runoff that pollutes waterways and destroys natural habitats.
Sugar. Production leads to deforestation and destroys natural habitats. It is water-intensive, which erodes the soils and contaminates waterways, damaging sea life ecosystems.