Entering a caloric deficit is key to weight loss because it compels the body to utilize stored fat for energy. When caloric intake is less than caloric expenditure, the body must tap into its energy reserves, effectively decreasing fat mass. It's important to create a moderate deficit to ensure adequate nutrient intake while promoting fat loss. Healthy weight loss strategies prioritize balanced nutrition and sustainable lifestyle changes to maintain results long-term, rather than extreme diets that can lead to health issues.