1. Carbs, especially when eaten on their own. If you want to have some coleslaw containing carrots, or a little bit of beetroot with your meal, that’s fine. But if you’ll have some sugar or honey with tea, coffee, that might kick you out of ketosis. Play around with it, have some and see how you feel, if you feel a bit worse, start measuring blood ketones, and see for yourself.
2. Eating too much, and of anything. Carbs, protein, and even fat. If you eat too much fat, sometimes by even like 15-20g, this can kick you out and you’ll feel crap. That’s why it’s important, especially initially, to weigh everything. If for example you don’t feel that great on 2:1 ration fat to protein, the try 2.15, don’t go to 2.5:1 straight away or 3:1, as more isn’t better. Find your ‘sweet’ (no pun intended) spot of the ratio and stay with it. It can change depending on stress levels, exercise, sleep, so pay attention, it’s your life.
3. Coffee, yep, unfortunately. Some days I can have 4 coffees and I’m fine, some days if I have more than 2 my ketones drop, and am felling worse. Don’t get me wrong, it’s not ever as shit as on blood glucose drop after carb meal, but it is worse than when feeling GOOOOOD on keto.