Hi.. Duodenal ulcer may be prevented by means of simple life style modifications.. They include dietary changes and stress management.. Diet changes include avoiding spicy and deep fried food, restricting caffeine consumption, restrict chocolate consumption.. Include plenty of vegetables, milk is an alternative for coffee and tea.. Be regular with your diet and avoid fasting..Follow up with good stress managing measures such as regular sleep, mind relaxing exercises.. Dietary changes is also needed to counter loss of weight.. But if you are losing weight soon a medical evaluation is needed to know the cause for it..