Hi,
Could be a few things:
- hidden carbs (sometimes they mount up without us even knowing)
- too much food (appetite often decreases on lchf, but habit can make us eat more than we need)
- too much fat (there is no virtue in stuffing unnecessary fat into every meal. Just eat enough to not feel hungry)
- too many carbs
How many carbs are you eating? And what are your blood glucose tests doing before and after food?
Our bodies can all cope with different amounts of carbs, and even if we are low carbing, we may not be low enough.
Hope this helps.