If you can sleep till 11am everyday, I don't see the problem. If you don't have class or work, or they start later in the day, you're fine. It's continuously changing the time that might lead to problems. For instance, you would like to sleep till 11am, but once or twice a week, you have to get up earlier at 8am.

The second poster has the solution. I can confirm that it works. At least for me. That's the easiest way to reset the clock.

I don't know about this detox thing, but the body does have a clock. It's called the Circadian rhythm. It's not terribly accurate, and in fact is probably closer to 25 hours.

It's kept in sync to the external day/night in your environment by your exposure to daylight early in the morning. If you were to go to the opposite end of the earth (Peru), after a few days, your body's clock will be in sync with the time in Peru.

If there is a "detox period", there is no reason to expect that it will be the same for every single person. After all, we all hear about "morning people" and "night people". There are people who wake up at 5am, and their mind is clearest at 8am. There are people who do their best work at 9pm.

What scientific study can you cite to justify this conjecture?

If you cannot sleep at 4am. Get up and do some work. I did that a few times last week. This was because I was very busy the past two weeks, and the worry about all the outstanding work that cannot wait was keeping me awake. This also screwed up my "sleep clock".

This past weekend, I decided to just reset my clock. Did not sleep Saturday night. I had no problem sleeping through the night on Sunday and Monday. Woke up early. No problem. Don't need any special diet or medicine.