If you’re serious about fasting and losing weight, I’m going to put this bluntly: cut all your bargaining and stick to zero-calorie drinks during your fasting window.
Most people think “what could a little creamer possibly do,” but the simple fact is it’s going to be enough to trigger an insulin response in your body. Once you trigger that response, your body is going to start storing your fat again as opposed to burning it.
Now, is it going to be that great of an impact? It depends on your own metabolism. Some people are going to snap back quicker than others, but in my opinion, it isn’t worth experimenting with. If you really need the cream with your coffee, then go for a zero-carb alternative so as to minimize any possible insulin response.