This has been me for the last two weeks! This is my second week of strict keto. I haven't eaten more than 1400 calories, no more than 20 carbs, tracking / monitoring religiously. I've lost nothing. In fact, I gained SIX pounds from Sunday to Friday. I was ready to jump off the roof. None of my clothes fit, my shoes were too tight- it was a freaking disaster. I could tell that I wasn't in ketosis, either. No keto breath, I wasn't peeing a ton, I was always starving....

I followed a strict keto diet for 18 months a couple of years ago, working with a nutritionist, a physician, etc, so I felt like I knew enough about nutrition to understand exactly how this works, and this weight gain wasn't making sense. I even started pulling things out of my trash can to make sure I was reading labels correctly.

I was researching everything I could think of to figure out why this was happening. Early last week, I had an awful migraine that just wouldn't go away so my doctor gave me a small dose of dexamethasone - a steroid. It stopped the migraine and I didn't think much else about it. Especially a week later. I googled dexamethasone keto diet and found out that this drug is given to cows as a cure for ketosis. It makes sense - farmers don't want cows to burn fat. I did some more reading and found out that some steroids can raise your insulin levels / blood glucose enough to knock you out of ketosis. This is all in addition to the wicked fluid retention that should not have happened on a keto diet.

It's been a week and I think it's finally leaving my system. I'm less swollen today (lost a pound overnight) and I noticed keto breath last night. I feel so much better knowing why this was happening to me.

I don't think you mentioned any steroids or any other medications, but it might be worth your time to talk to your doctor or a pharmacist about how they can affect your weight loss.