A Green day is a day you are eating with attention to the quality and spread of food that leaves them feeling their best and helps them achieve the goals they have.
A Yellow day might be a day where it was mostly routine with some sort of spontaneous in the moment extra like a snack or fun dessert.
A Red is a day with multiple extras like a weekend spent celebrating with friends.
There is also a projection feature on the app if you select a day in advance, you can assign it a color and instead of coloring it in, it outlines it. This is a good way to keep track of social events you know are coming up and surround them with green days! Remember, the colors do not say good or bad, they are simply a way to see what your week and month has developed into.