Tea: It's good for you, but only if you don't drink too much of it. And by "too much of it," we mean a pitcher made with 100 to 150 tea bags. That's how much a Detroit woman drank each day, and doctors eventually realized that her years of back, arm, leg, and hip pains were caused by the tea habit, according to the New England Journal of Medicine. It seems the high level of fluoride—brewed tea has a bunch—was to blame, the Detroit Free Press explains. It caused a bone disease known as skeletal fluorosis, and also made her teeth brittle. They all had to be removed. After counseling, the woman is no longer drinking tea and is doing better.