The unequal distribution of wealth in Sao Paulo has led to an increased crime rate over the years. If you are not careful, chances are that you will be pick-pocketed or mugged in the city. Always remember to take only as much cash as you need when you are going out. Keep some change and a few old credit cards with you when you go out so that, if you do get mugged, you won’t lose much. Also, leave your valuables (cameras, jewelry, etc.) behind when going out and avoid wearing seemingly expensive clothes or shoes. Do not park in deserted neighborhoods, especially at night, and do not display cash in public. Try and use the ATM as little as possible and, if you must, make sure no one is watching. Also, do not talk to strangers, especially at the airport, and do not agree to handle or hold parcels for them. You must not give out personal information, such as where you are from, where you will be staying, etc., to anyone. If you are driving, keep your doors locked and windows rolled up at all times, particularly at night. In fact, driving at night is not at all recommended, especially for women.
You must always remember to drink bottled water (including when brushing your teeth) when in Sao Paulo since several hotels/hostels/apartments are not particular about keeping their water tanks clean. Additionally, make sure you have your yellow fever shots in place. Do not eat fruits and vegetables without washing them first and do not eat from street vendors. Also, have beverages of brands you recognize, and if you do want a tropical drink, have it from a safe, reliable place. Failure to do any of this can cause diarrhea. Finally, remember to consult your physician about ways to prevent meningitis before your travel to Sao Paulo.