Normal
It is not necessarily that the water is "bad," it is that your body is unaccustom to the water in that area. You can have Montezuma's revenge going from city to city in the US for this reason. All drinking water has some stuff in it. With that said, yes, I'd be careful in Cozumel because the water there has more "stuff" in it than you are used to. Unless the water used in the restaurant/hotel/resort is bottled or filtered at the site I wouldn't eat veggies washed in water (lettuce), fruit that isn't peeled or ice cubes.Be sure to take some Imodium AD with you
It is not necessarily that the water is "bad," it is that your body is unaccustom to the water in that area. You can have Montezuma's revenge going from city to city in the US for this reason. All drinking water has some stuff in it.
With that said, yes, I'd be careful in Cozumel because the water there has more "stuff" in it than you are used to. Unless the water used in the restaurant/hotel/resort is bottled or filtered at the site I wouldn't eat veggies washed in water (lettuce), fruit that isn't peeled or ice cubes.
Be sure to take some Imodium AD with you