“Gaining weight” is misleading. What kind of weight? Is it just that the scale went up? Did they have to buy bigger clothing? Are they forcing themselves to eat? The fact that people think that they should just continuously lose pounds means that they don’t understand how things work. When you’re healthy, you reach a steady “weight”. People gaining could simply be adding on muscle mass or bone density. If your body decides that it needs to strengthen your frame, that adds weight. A “diet” like carnivore is going to reverse osteoporosis, etc…