If you are traveling to Mexico there are a few health issues you need to think about. The first thing to start off with is the drinking water. You have always heard that you should not drink the water in Mexico, this also includes when you are going to use ice in your drink. When drinking water you should always assume the worst. If you are going to drink water or any type of juice make sure that the seal on the bottle is closed. A lot of places recycle bottles and reuse them, if you see that the bottles top is not sealed then you should be extra careful and decide if you really want to drink that water or not. The only reason this is, because some places that are recycling the bottles will fill the bottle with tap water instead of clean fresh water. You might think that you were drinking clean water but instead you were really drinking tap water. This is how some people get sick when they travel to Mexico. You should also have this precaution when you are going to drink bottled fruit juice. In bottled fruit juice they could add water in it if they do not want to fill the whole bottle with the fruit juice. If you want to drink milk, you should make sure the milk is pasteurized. If you are suspicious about the milk, make sure that you boil the milk before you drink it. Yogurts are normally fine to eat when you're in Mexico. Other stuff that should be OK are tea and coffee since the water is brought to boil before you prepare it.
The easiest way to purify water is by boiling it. Boiling water for five minutes will make the water satisfactory enough to drink. If you are in a high altitude remember that water boils at a lower temperature, so germs and bacteria is more likely to be in your water because they will be less likely to be killed during the boil. If for any reason you can not boil your water, your water should be chemically treated. There are chlorine tablets like Puritabs, Steritabs or other brands of chlorine you can use that will kill most of the pathogens in the water. The chlorine tablets will most probably not kill those that cause giardia and amoebic cysts, read the label before you use it.
Another thing you could use in purifying water is iodine. Iodine is very effective in purifying water and is available in tablet forms like Potable Aqua. You should also read the label before you use it and always remember that too much iodine could be harmful for you.
There are different standards for food. If you are going to eat a salad, your vegetables and fruits should be washed with purified water and peeled before eating. You should be careful getting ice cream from outside vendors, the ice cream could have melted then refrozen and sold. Mussels, oysters and clams and undercooked meats should be avoided as much as possible. Remember, steaming your shellfish does not make it safe to eat.
You should try eating at restaurants where it looks clean and well run, and the food is probably safe to eat. You should eat at a restaurant where there is a lot of traffic coming in and out of the restaurant, this means that the food that is stored in the restaurant has a less chance of having the food to sit around for ages then reheated. So try to avoid empty restaurants as much as possible.
If you do not get the right foods you should eat nuts and fruits that you can peel instead. If you do not get the right nutrition then you will start to lose weight and put yourself in a health risk. If you do not feel the need to urinate or if you are urinating dark yellow that means that there is something wrong. Always carry a bottle of water with you at all times, and drink water even when you do not feel the need to drink water.