Common side effects of extreme dieting include nutrient deficiencies, fatigue, and irritability. Such restrictive diets can lead to a lack of essential vitamins and minerals, impacting overall health. As energy levels drop, individuals may experience decreased metabolism, muscle loss, and potential anemia. Psychological effects often include anxiety about food and binge-eating episodes when diets become unsustainable. Long-term adherence to extreme dieting can lead to a negative relationship with food, increasing the risk for eating disorders and poor physical health.