I’m new to doing straight Keto myself… Started on January 5th and did great until a few days ago when I fell off.
In 21 days I lost 12.6 pounds, lost 2.5 inches off my waist, went down 4.5% body fat.
I fell off the keto diet and ate carbs… then I ate more because I had already screwed it up… I had pie and cereal and basically things I had missed from going cold turkey for 3 weeks…
The effects on my body were that I gained fat and water weight, and my stomach was in terrible shape and I had a lot of time to think about what I had done while I was in the bathroom the next day… a lot of time! ugh!
Physically I felt bloated and mentally it was a failure that I took pretty hard.
I few days later when things had started getting back to normal, I weighed in and did measurements and calculations and it turned out that I had lost most of what I had gained but I had retained more lean mass. I am assuming that insulin sensitivity from 3 weeks without insulin along with trying to stay active, allowed my body to allocate as much to lean mass as possible.
I have done some reading in the past (years ago) about CKD - cycling a carb day in with a keto diet - in the context of bodybuilding, and there are people who use that strategy as a way to build lean mass while losing fat. I guess that works, but the stomach issues seem like that would be a pretty significant negative… My opinion at this point is that the longer someone can stick with the keto diet without falling off, the easier it will be to stick to it.
I have a friend who is also doing keto and we started at the same time… We both fell off at the same time, and she had the same issues I did, but she also has allergies (some foods as well as cat and dog allergies), and after falling off twice and eating carbs, she has experienced a skin rash (associated with cats) that she noticed she had not been having issues with while sticking to the keto diet. So something that happens while on Keto is helping her non-food allergies in some way.