I visit at least once a year and am not used to the water. I stay at good hotel and take a normal shower and brush my teeth normally. I swim in the pools without any issues.

When I eat breakfast in the hotel, I eat eggs and fruits.

If I buy fruits on the street, I eat them in the room after cleaning them with bottled water. I NEVER eat cut fruits on the street or mid quality restaurants.

Usually, the western diets cannot handle the amount of spice(not heat but masala) that is put in restaurant food which is over and above than most home cooked food.

Even I get sick at least once while in India. Something I expect and deal with.