I struggle with this a lot too. Ultimately you just have to be patient with yourself and try different strategies until you find one that works.
The things I’ve found success with to gain are trying different foods until I find ones I like enough to gorge on, cooking my own food, appetite stimulants (ONLY use these if your doctor prescribes them. I’ve found most doctors will prescribe them if your appetite is severely low, you’re not fat yet, and there’s no major contraindications), and heavy cream.
Heavy cream is by far the best of these if you have a truly awful appetite. Don’t have it at the beginning of the day, or it will make the problem worse. Instead, eat as much as you can during the day, and then chug as much cream as you can manage without gastrointestinal distress before bed. The first couple times you try this it makes it impossible to sleep, but you get used to it quickly and can sleep fine after that. Even with relatively small amounts of cream, a single cup each night on average, I saw dramatic results when I used it. Furthermore, in my experience cream weight sticks well even when you return to a normal diet.
Eating fast is supposed to help if you’re able to do it, because you can get more down before realizing you are full. Unfortunately, I’m really bad at eating fast because I always either get distracted or get sick, but maybe you will have better luck.
2 years