What should your caloric intake be if you are 5 feet 6 inches tall and want to up your intake from 800 in order to maintain your weight at 110 pounds and you are an active person?

800 calories a day is far too few for any person of your dimensions, even at a sedentary activity level. Your BMI places you as certainly underweight. Your current weight is so low that you would be prohibited from appearing as a runway model. You risk serious health problems if you do not increase your weight and caloric consumption. You may have an eating disorder. Please seek appropriate psychiatric treatment for an evaluation. http://www.caloriecontrol.org/calcalcs.html According to this calculator, you need at least 2200 calories to maintain your weight. Gaining enough weight to reach a healthy level would require more than this. A healthy weight for you would be 130 pounds.