Alternate-day fasting (ADF) has gained popularity in recent years. The diet consists of a "fast day" where an individual consumes 0-25% of their energy needs, alternated with a "feast day" where a person is permitted to eat ad libitum.This study examined eating behavior traits of successful weight losers during alternate day fasting.Obese participants ( n = 34) took part in 12 months of ADF and were grouped into a high (≥5%) or low-weight-loss (<5%) group post-treatment.The high-weight-loss group demonstrated increased ( p = 0.04) fullness, decreased ( p = 0.03) hunger, increased dietary protein intake (15% to 20% of kcal, p = 0.04), and better adherence to fast-day calorie goals.Thus, individuals who achieve clinically significant weight loss with ADF demonstrate improved satiety, increased protein intake, and better adherence to fast-day calorie goals.