Is coffee really beneficial?

Eat Right 4 Your Type book says that coffee is good for type A. I had kidney infections that nearly killed me (E. Coli) about 10 years ago. I cut out soda at that time, and never had been a coffee drinker. The Dr. said my kidneys had no damage but I believe differently. I haven't had any problems but I am very careful. I drink a glass of wine every day and outside of that drink mostly water, green tea, and soy milk.

So does coffee harm the kidneys? Is it really beneficial for us type A people? I'm thinking about drinking half a cup a day or so.

BTW, I am attention deficit, so the caffeine actually slows and calms me down. Tweet