I did not explode

Yesterday at lunch I was eating banku and okra stew at the night market. I also had two bags of water to wash it down with. The woman across the table from me, however, was making a lot of strange hand gestures at me in a panicked way. At first I thought she might be a witch trying to curse me with juju.The man sitting next to her, however,  said she was dumb as in mute and was trying to tell me not to eat and drink water at the same time or my stomach would explode. Apparently this is a widely held Ghanaian folk belief.