Obesity is a global outbreak associated with different dietary patterns. As the surge in the number of obese people grows, understanding the role of diet is crucial for developing nutritional strategies for the prevention of obesity. Western, Mediterranean, plant-based, and low-carb diets were examined in this article to assess their impact on obesity-related outcomes. Studies reflecting these diets are reviewed, and a comparison table is provided to determine how each diet prevents or contributes to obesity. Measuring body mass index (BMI), waist circumference, and fat percentage are key factors in determining obesity. The findings show that while Mediterranean and plant-based diets present protective effects against obesity, Western diet is associated with weight gain and metabolic diseases. Although a low-carbohydrate diet is effective for weight loss in the short term, it presents unpredictable long-term results. However, further research is needed to evaluate long-term adherence in metabolic outcomes.