There are two things we want to do when it comes to eating in other countries:
1. We want to stay as healthy as we can and avoid sickness caused by what we eat.
2. We want to be sensitive to the people we're visiting and avoid offending them through our eating habits.
Here are some tips to help you with this:
Bring snacks, purchase bottled water after you arrive (in most countries), and of course you may drink sodas or canned or bottled drinks. Use bottle water for brushing your teeth and do not use ice cubes unless they too were made from purified water. It is generally safe to eat fruit, which is peeled, but it's good to wash it in pure water first.
When traveling in ministry, the churches may prepare meals for you. It would be impolite to refuse to eat their home-cooked meals. You must be careful about your facial expressions and what you say among yourselves. Remember, you are representatives of the Lord Jesus Christ Himself. The Bible says we are to eat what is set before us (Luke 10:7). If we pray and give thanks to God for it, He will bless and sanctify it for our use (I Tim. 4:4).