Thanks for reading and your input! I have never been to Thailand so I am not so sure about the situation there but, in India, being vegetarian definitely helps. Obviously the only sure fire way to prevent illness is being vigilant and I hope it didn't come across I was saying simply being veggie will be enough in India. The sentiment was just meant to be that it will drastically limit the chances of becoming ill. Potatoes, for example, are something which can cause illness if not heated properly due to the staph bacteria. However, the illnesses you get from veg (generally) are not as threatening as those from meat and grains.

I definitely will keep you in mind! Likewise if you're ever in London