Lifestyle tips

There is a chance you're undereating regularly if your body is responding this way. One way to find out is to use an app like MyPlate and track what you eat normally for a week or two. You'll be able to see if your body weight/size is being supported.

When I wanted to start gaining, I used it and discovered I was undereating. I realized how much more effort I needed to put into my diet to gain while staying as healthy as possible. 😁

Agree with the above. In my experience with my feedee, super heavy and rich meals just slow you down and make you more sleepy.

Not necessarily. You can undereat a little every day and maintain your size. If your body is used to your present intake, it has learned to function at this level. But as you said, when you increased calories, you felt a difference. There's a chance you wouldn't lose weight unless you had a more significant calorie drop per day - which isn't really healthy.