For the last 10 - 15 years I maintained carb intake at around 20g. It was very comfortable and so easy, nothing in my refrigerator beside meat, cheese, eggs and butter.
However, there was a huge drawback - nightly leg cramps. I have heard all the advice - it will pass after some time, up your magnesium, potassium, more salt in your diet. No, nada, zip, zilch. It never went away.
A foot cramp is an annoyance, a calf cramp is worse but a thigh cramp is enough pain to almost pass out.
Sometimes weeks would go by without cramps and I would think this is it I am free of this. But then it would be back, sometimes every single night several times.
I never went to bed without having a bottle of tonic water on my side, I even traveled with it. Tonic water is a true miracle for cramp sufferers, a glass or just a half and within a couple minutes the cramp is gone.
Anyway, a couple of months ago due to rare circumstances my carb intake went up for a few days and bingo - no cramps. That finally did it, now a days I maintain my carbs at about 100g and enjoy peaceful nights.That is not enough to keep me in keto, even though for mainstream nutrition it is still way too low. I still shy away from fruits but i find that I enjoy eating veggies again.