Obesity has multiple etiological factors. It is related to stress, body make up,genetic structure as well as basal metabolic rate. When you are in stress either physical or mental your balance between appetite and satiety centers(centers to monitor appetite and food intake in body) is disturbed. So your craving for food increases and you not satisfied though you take enough meal. Which lead to weight gain. However food you mentioned in your diet is also high calorie like chicken and fish. They may also be responsible for weight gain. You should count calorie of your daily food and strictly maintain it 25% less than roughly than your body requires. It will help you to reduce weight.In another way you can burn more by exercises. No need of any health supplement I think. Vegetables like cabbage, broccoli, tomatoes are the food which give minimum calorie with maximum appetite satisfaction. But you need to contact your doctor also for hormonal evaluation as hormonal imbalance like thyroid also may affect your food habit. And ultimately if all these due to stress , you need good counseling to motivate yourself for healthy lifestyle and food habit.