L-theanine at 200-300 mg before bed is extremely useful for canceling excessive caffeine while trying to sleep at night. Add piperine to the mix for possible further cancelation of caffeine. [PMID 35684048]
That's the idea, vitamin D was used as a placebo. They bought vitamin D supplements rather than cellulose because the supplier sold both L-theanine and vitamin D and the pills looked (nearly) identical.
Taking vitamin D once, right before bed will do nothing. Our bodies don't use it that way.
Cholecalciferol = weeks
calcidiol = hours
read as if you're perfectly healthy, at minimum it's 24 hours. What you're talking about is probably placebo effect. For reserves to start building up to the point where your body has "enough" calcitriol, it takes weeks
* CalcitrolLevel: float
* CalcitrolReserveCapacity: float
* Is_Energetic: bool
Imagine the following equation:
* Is_Energetic = CalcitrolLevel > 90% of CalcitrolReserveCapacity
For most people, it will take days, weeks, or even months to come above 90%. But for those who have dipped just below 90%, such as to 89%, if they're optimally healthy in other ways, they will see a rapid rise in energy by high dose D3. If it's not this, then there is something else going on physiologically to explain the subjective effect.