Hormones significantly affect weight gain and loss by influencing appetite, metabolism, and fat storage. Hormones like insulin, ghrelin, and leptin play vital roles in regulating energy balance and hunger signals. Insulin facilitates glucose uptake, while ghrelin stimulates appetite, and leptin informs the brain when to stop eating. An imbalance in these hormones can lead to weight gain or difficulty losing weight. Understanding these hormonal impacts can help individuals develop effective strategies for weight management, taking into account not just caloric intake but also the hormonal fluctuations that affect their physiology.