Metformin helped the person asking the question lose weight and clear their acne after being diagnosed with PCOS. In 2 weeks on metformin (1000mg per day), they lost 8 pounds without dieting. Many others with PCOS have also lost weight successfully with metformin. Maintaining a diet high in lean proteins, whole grains, fruits and vegetables while limiting sugar and refined carbs can help further with weight loss and PCOS symptoms.