Dear friend , i understand your query.. but i am surprised to hear you need to gain weight .. it s better now a days to be little under or near normal weight for your height .. in this world of lifestyle disorders ... as long you are healthy no need to worry about your weight ... some dont gain weight as they have more of brown adipose tissue which dissipates energy you consume in the form of heat ... so avoids weight gain .. take nitrious food and more of proteins that helps in building the body proteins ...take fish , chicken and meat ... sprouts, green leafy vegetables, and keep exercising .. you will be alright .. do contact us for more queries ... thank you