The objective of the study is to compare subjective appetite ratings and after-meal and 24 hour blood glucose levels within overweight and obese female subjects consuming either a standardized 3 day low calorie diet supplemented with a viscous fibre known as PGX (treatment) or a rice flour (placebo control). Each treatment phase will be 3 days in length and separated by 3 week washout phase, so subjects will also be acting as their own control. Subjects will be randomized to either start with the low calorie diet with PGX or the low calorie diet supplemented with rice flour. We hypothesize that the 3 day LCD with PGX will elicit an improved appetite score compared to the 3 day LCD supplemented with the rice flour placebo control.