The last 4-5 nights I have not been eating anything after dinner (about 6 oclock or so). The first couple of nights while sleeping, I kept feeling like my brain was waking up in the middle of the night while my body stayed asleep (if that makes any sense at all), and then the last couple of nights I almost completely woke up just before sunrise (I didn't look at the clock, but I could tell the sun was just barely starting to come up) I am used to sleeping til 9 or 10 so I just grumbled and went back to bed. I was awake, but not quite conscious enough to make myself get up early. Before I started doing this, I would sleep all the way through the night, up to 11 hours sometimes. Could it be that previously I needed more sleep due to digestion while sleeping and my body is trying to wake me up early now? Has this happened to anyone else?
I usually stop eating at 6 pm. I sometimes sleep through the night, but often have biphasic sleep.
Carbs at night can help me sleep all the way through, also less water, no alcohol and Magnesium supplements.
When this happened to me, it was related to hypoglycemia. I found that varying the time of my last meal resulted in a variance in the time that I awoke during the middle of the night. Insulin/cortisol issues related to blood sugar. I think the potential causes are various, but in my case it seems to have been related to potassium deficiency. Once I started eating foods higher in potassium, I slept through the night with no problems.
Fasting does not do this to me but when I decrease carbs I cannot sleep past 4:30 am for about a week. I do not know if it's a symptom of ketosis or what. You may have kicked into ketosis.
This does not happen to me when I IF. Maybe if you skip breakfast instead and then eat a larger/later dinner?
Have you been going to sleep earlier? It's a natural sleep pattern to wake up in the middle of the night:
"We now also know that pre-industrial families commonly experienced a "broken" pattern of sleep, though few contemporaries regarded it in a pejorative light. Until the modern age, most households had two distinct intervals of slumber, known as "first" and "second" sleep, bridged by an hour or more of quiet wakefulness. Usually, people would retire between 9 and 10 o'clock only to stir past midnight to smoke a pipe, brew a tub of ale or even converse with a neighbor."
It's a natural sleep pattern. People used to wake up in the middle of hte night, hang out or have sex, and then go back to sleep. When it happens to you, just own it - get up and do something for a little while and go back to sleep.
Others have answered other parts of your question so I'll just say, "Yes, I seem to need fewer total hours of sleep now because the quality of my sleep is much improved.
Unlike many others, particularly people in their 60s, I usually sleep straight through now which is a drastic change from my fitful sleep on SAD. And, as you described, I wake up at first light before sunrise regardless of what time the clock may say.
I also wake up totally alert unlike the grogginess of the past. The only negative is that if I wake up or something wakes me up, regardless of the time, that's it and I can't really go back to sleep any more. The other night I received a wrong-number call at 2 am and never fell back to sleep. I wound up playing games on my Kindle and watching TV and never got tired or drowsy that day.
So, a healthy well-rested body can be less willing to indulge us in lazy mornings. I get a little nostalgic sometimes because I lazed in on weekend mornings all my life.
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