Hello and thank you for your question.
Spicy food, citrus food, garlic, onions are known to in food trigger category for creating a heart burn.
As you have travelled different countries and have tried variety of foods and drinks that can also cause to upset the GI flora. Even alcohol can upset your stomach lining.
So it is not unusual to develop heart burn after you eat your food. Keep a food log to help you track the foods that are your heartburn offenders, and try to develop a list of safe foods.Foods like broiled chicken, baked sweet potatoes, toast, or cottage cheese, are on the safe side of the heartburn food list.
For now try avoiding the foods that cause heart burn and try to eat in little portions.
Try to limit soda, coffee, alcohol and chocolates as they would make it worse.
Do not consume oily or fired foods during dinner time.
You try chewing gum as gum stimulates the production of saliva, which is an acid buffer. Plus, chewing gum makes you swallow more often, which pushes those nasty acids back out of your esophagus.
Try taking tums too that can also neutralize pH in your stomach without any side effects. It may take time your stomach to adjust but if it gets worse than seeing a GI doctor would be recommended.
Please get back to me if you have any further questions. Thank you.