Saturated fats promote inflammation. If you're doing a more traditional keto diet with butter, fatty cuts of meat, etc., that's where it comes from.
Can you show me evidence that saturated fats in the absence of sugars promotes inflammation? I stick with mainly monounsaturated fats with some good polys as well but certainly still get a decent amount of animal fat. The net effect I have seen of keto in studies shows a decrease in inflammatory markers.