One of the very common myths about the LCHF / ketogenic diet is that it’s a high protein diet. It’s not!
The confusion comes from calling it a “low carb” diet. The truth is there are two “low carb” diets. One is where you pump up the protein and the other where you eat predominantly fatty food. The latter seems to be actually bad for you. Time.com reports there could be a downside to high-protein diet: it reduces postprandial insulin sensitivity.
The original paper states that while a high-protein diet preserves lean body mass in weight loss, but at the same time prevents the weight loss-induced improvement in insulin sensitivity and alters weight loss-induced transcriptional changes in muscle.