In most cases, primary food production occurs in a process called photosynthesis, which is powered by sunlight. In a few environments, primary production happens though a process called chemosynthesis, which runs on chemical energy. Together, photosynthesis and chemosynthesis fuel all life on Earth.
Eat 5 â 7 servings of meat and beans per day. This depends on the total number of calories you consume in a day. 1  If you consume 1600 â 1800 calories, eat 5 servings per day. 2  If you consume 2000 calories, eat 5 Â½ servings per day. 3  If you consume 2200 calories, eat 6 servings per day. 4  If you consume 2400 â 2600 calories, eat 6 Â½ servings per day.
As a general rule, the more fruit and vegetables you eat the better. I recommend 7 -- 12 servings each day. The Department of Health and Human Services (HHS) and the Department of Agriculture (USDA recommend 9 servings of fruit and vegetables per day for men, and 7 for women.