"Weight cycling" is what Alexon defines as that frustrating up-and-down that tends to accompany fast-fix or trend diets. While following the latest trends might seem appealing and produce quick results, Alexon cautions that it's not actually a habit you should get used to. "The problem with some of these trendy diets is that if it's not sustainable, it basically leads to weight cycling, which has a lot of potentially negative health concerns," she explains. "If you're doing something short-term like this, it's not a great approach and often leads to weight regain." Instead, build sustainable habits, and eat balanced meals.