Before you book your trip, check the Centers for Disease Control website, to see what immunizations and preventative medications (like malaria pills) you should get before going to a particular country.
When it comes to not getting sick during your trip, it’s best to be over-prepared so you can quickly go to war on anything that could cause you to spend a day or more of your trip curled up in bed, feeling like crap.
Our bodies are 60% water. H2O keeps our cells happy and vigilant; and happy, vigilant cells keep us healthy. Travel can be dehydrating. Airplanes are super dehydrating. Adjusting to distant time zones and environments is dehydrating. Hours of hiking or city walking are dehydrating. Our bodies are 60% water.
Vitamin C should be a major part of your health regimen when you travel to a foreign land: via plane; across multiple time zones; or to a developing nation.
If you're not mindful of what you're eating overseas, there's a chance you'll come down with a not-fun case of diarrhea... food poisoning... or, worse, a life-threatening disease like typhoid fever.