As per your BMI you're presently on a healthy weight. If it was a sudden weight loss, I would advise you to visit a MD general medicine so that you can be examined and undergo necessary investigations to find the underlying cause and have it treated accordingly. The following steps may help with the gas problem: - Don't skip meals, you may not feel like eating but in such conditions you should have the reduced amount in frequent intervals(i.e. 3 square meals broken down to 5 or 6 as you can tolerate) and slowly increase as you get better. - Reduce/ Avoid spicy,fried, fatty, junk and oily food - Avoid/ Limit drinking coffee, tea and carbonated drinks to once a day - Exercise regularly (30-45mins per day, maintain a healthy weight as per your BMI) - Increase daily intake of water to 3 liters - Avoid/Stop smoking and drinking if you have the habit - Reduce stress through methods such as yoga/meditation.