Hello Walter,

Thank you for posting your question. I suspect this is going to be difficult to resolve in a forum because to really get to the bottom of your concerns might require a lot of back and forth dialog, much of which may not be appropriate in a public forum due to privacy concerns. Do you keep a food log? That might be a good idea. You might want to log other variables as well such as your bed times.

Sometimes being thin is strongly influenced by genetics and sometimes there might be a medical issue going on. You might want to consider making an appointment with a plant-based physician to seek their advice. 

Sean

PS. As you study the Starch-Smart System you will learn what foods are low and high on the calorie density scale. This information could be helpful to you in deciding how to ensure you consume enough calories.