Is it possible that a person with Early Onset Alzheimer's would not recognize hunger?

Is it possible that a person with Early Onset Alzheimer's would not recognize hunger thinking he is sick? My husband has been complaining of indigestion and food helps, so wondering if he's not recognizing this feeling he has? Is that possible? He gets really morose when he doesn't feel good. Even a mild headache sends him off the edge. Frustrating for me as his spouse and caregiver as I'm not sure what's really going on.