Gas is a byproduct of digestion by normal gut bacteria. Any food rich in carbohydrates can cause gas production and not only junk food. Also If you are doing a desk job or your job requires sitting at one place for longer duration, it can produce gas.
Next Steps
food rich in carbohydrates and sometimes fibres can itself produce gas , so eat food rich in proteins and healthy fats. Eat slowly and chew well to avoid swallowing excess air. Try to take a short break every 1-2 hours and do the walk or any other light movements for 5 minutes.