I still sometimes feel a bit lightheaded if i dont time my packs well. I find that splitting the packs helps a lot!! I try now to have half a shake in the morning for breakfast, a full shake at about 3 and 6 then another half pack at about 8. It tricks my mind into making me think im having more too which i always a bonus lol. theres also the option of having 2 packs and using the 3rd to add to coffees all day. I find i get about 4 vanilla coffees out of one pack, and i feel fuller when i do that too. xx