Been on Keto for 5-1/2 weeks…6 on Friday. Doing well and loving this way of life. So yesterday I woke up and wasn’t hungry and skipped breakfast. Was hungry and both lunch and dinner and ate till full. I’d estimate my calories yesterday were around 900 calories. Same thing going on so far today. Should I be concerned that I am not hungry and or not getting enough calories and that would affect metabolism and or weight loss?
If needed: 5’10", 235 lbs, 37 year old male.
It’s natural for your appetite to come and go when you’re just starting on Keto. But I would keep an eye on it. Long-term, eating calories that few could potentially become a problem. I think tho your appetite will likely return, so that probably won’t become an issue, but just keep an eye on it.
@anon2571578 Thanks, hasn’t been an issue till last two days. Just wasn’t sure if I should eat past full to get the calories up or just follow the eat till your full model.
It’s a strange feeling to not be hungry for extended periods of time and feel great. It’s not anything to worry about. It sounds like you are reaching a fat adapted state and this is when fat loss can be the most dynamic. Just trust the process and eat when you do get hungry.
My appetite fluctuates daily. You’ve been eating this way long enough that you can most likely trust your hunger and satiety. Just keep the carbohydrate low and keto on!
Mine does also. Lately, my first meal is around 1 or 2ish. Today, I’ve been pretty hungry since early this morning and had to eat a few nuts. Now at 11:30, I can’t wait to eat lunch and hope it will last me until I get home this evening.
I had (still kind of have) the same concerns. My calories were close to yours for almost the entire time I’ve been keto, and I have also been feeling full after meals, except I’ve been mostly OMAD. I’ve been losing a great amount of weight, but as a precaution I tweaked what I’ve been eating a bit to up my calories from 900ish to 1500-1700/day this past week. Hopefully I still see some weight loss at my next weigh-in
I think you are safe. Your body has likely just realised that its energy storages are way past full, so it focuses on getting the essential nutrients from food, and not much more.
If you worry about your metabolism, you could add in occasional high protein lots of snacking days. But it really helps working out first. I don’t count my calories, but trust that my body would tell when it needs specific nutrients. This mostly means that if I suddenly want meat or fish, I’ll get some for dinner that day. Meat is only enticing when my body wants the protein.
As others have said, let your hunger be your guide, that includes the inevitable day that you just can’t eat enough. I usually eat two meals per day and am adding in more OMAD days…then there are the days I feel like I need a butter IV. If that’s what my body tells me, that’s what I do, only I eat some butter rather than stick it in an IV bag 
At first, I was worried obsessive about the same thing. I just wasn’t hungry. And then week 10 came, and my appetite with it. Then I found myself hungry a lot. I added a little more fat and cut back slightly on protein, and that did the trick.
It will regulate itself. Most likely, you’ll wake up one morning and start being hungrier.