I had the same problem. It doesn't bother me in tea or in some other foods (I did a little experimenting), but in coffee...it just didn't work, for whatever reason. Maybe it's just 'cause I'm really picky about my coffee.
But I've finally gotten to the point where I only drink coffee once in awhile, so it's not as big of an issue. And I'm not doing Atkins...just trying to cut back on sugar and such.