Common misconceptions regarding calorie intake include the belief that all calories are equal regardless of their source and that cutting calories drastically leads to sustainable weight loss. In reality, the nutritional quality of calories matters; for instance, 100 calories from fruits and vegetables provide essential nutrients compared to 100 calories from processed snacks. Additionally, extreme calorie restriction can slow metabolism and lead to muscle loss, making it harder to maintain weight loss long-term. Understanding these nuances is crucial for making informed dietary choices and achieving sustainable health.