"Starvation" mode

Every dr has a different plan, but I start with the calories from protein (4 cal per g).  So if I "need" 100g protein per day, that's 400 calories.  Carbs are also 4 cal per g., and fats are 8 cal per g.  So just figure out how many grams of each of those you're supposed to have each day and add up the calories. :)  During WL I figured 20g carbs was the goal (80 cal) and the rest from fats or additional protein.  Now I have more carbs (I am in maintenance).