The official line is one a day (and not on the same day as water flavourings either) however, I had 2 a day on most days of Sole Source - if it slowed my losses then so be it as it kept me on the plan. I don't think I would have carried on without my mousses as I loved them soooo much. The mix only adds an extra 20 calories or so anyway, so a few jogs up and down the stairs will sort that one!