How it works is that each flavor point is 1 calorie that is added to the subjects weight every 5 seconds, multiplied by the number of ‘Flavor Boost’ Fat Point upgrades you have. Flavor points add up each time the subject eats, and then are reset to 0 when a new day starts.
So if you feed her 100 Gummies- worth 400 Sweet points in total- with only 1 ‘Flavor Boost’ upgrade, that’s a flat 800 calories every 5 seconds until the end of the event, enough to passively gain just over 16 lbs on a long day on realistic difficulty.