While all forms of significant weight loss may result in some muscle loss, there may be an increased likelihood of muscle loss in people on a ketogenic diet, especially if calories are restricted too low. Because while in ketosis the body doesn’t have enough sugar to burn, it may also break down proteins for energy, in addition to churning through fat. This may be somewhat compensated by the moderate protein included in the diet and if you are actively lifting weights.
The truth is we don’t yet. It’s possible that the keto diet is successful as just another way to restrict calorie intake. Human research has not yet shown any conclusive mechanism for why a keto diet would be more beneficial than any other calorie-controlled diet for weight loss.However, there are some theories behind why ketosis may be more beneficial in helping some lose weight (15,16,17).
^ Jump up to: a b c d e f g h i j k l m n o p q r s Kossoff EH, Zupec-Kania BA, Amark PE, Ballaban-Gil KR, Bergqvist AG, Blackford R, et al. Optimal clinical management of children receiving the ketogenic diet: recommendations of the International Ketogenic Diet Study Group. Epilepsia. 2009 Feb;50(2):304–17. doi:10.1111/j.1528-1167.2008.01765.x. PMID 18823325