Originally posted by Eladar
I'm sure they are upping it due to people thinking more is better.
But as I said, I'm pretty sure she is taking too much.
But going with your numbers, what percent would actually hit the blood stream if the person is only absorbing 5%? The stomach does destroy much of it and if a person has absorption problems, then even less makes it through.
http: ...[text shortened]... elatonin.aspx?activeingredientid=94
http://www.easy-immune-health.com/melatonin-overdose.html
Don't know that % number. I'll gargle it, see what pops up.
I found this, a ridiculously high dose for the study, 80,000 micrograms! And the results show it, from 1984, a bit dated maybe.
This is just the abstract.
Neuroendocrinology. 1984 Oct;39(4):307-13.
Bioavailability of oral melatonin in humans.
Waldhauser F, Waldhauser M, Lieberman HR, Deng MH, Lynch HJ, Wurtman RJ.
Abstract
We administered crystalline melatonin (80 mg) in gelatin capsules to 5 young male volunteers and measured serum and urinary melatonin levels at intervals. Changes in serum melatonin levels were best described by a biexponential equation with an absorption constant (ka) of 1.72 h-1 (half-life = 0.40 h) and an elimination constant (ke1) of 0.87 h-1 (half-life = 0.80 h). Peak serum melatonin levels, ranging from 350 to 10,000 times those occurring physiologically at nighttime, were observed 60-150 min after its administration, remaining stable for approximately 1.5 h. The fraction of ingested melatonin that was absorbed, estimated from the area under the curve describing serum melatonin concentrations as a function of time after melatonin administration (the concentration-time curve), varied by 25-fold among subjects. 3 additional volunteers received three melatonin-containing capsules (80 mg each) at 60-min intervals. This regimen extended the duration of elevated serum melatonin levels to 4-6 h. Melatonin excretion closely paralleled serum melatonin levels until 9 h after the hormone's administration, after which urinary levels tended to be higher than those predicted from serum levels. However, the area under the concentration-time curve for serum melatonin correlated well (r = 0.96) with the cumulative melatonin excretion during the initial 15 h after melatonin's administration, indicating that either approach can be used to estimate the absorption of orally administered melatonin.
PMID: 6493445
Notice, it says the measured amount internally was 350 to 10,000 times higher than a normal production rate, I did not see actual numbers but that is indicative,
80,000 divide by the smaller number says the body produces about 230 micrograms if those numbers are correct, so it says the bioabsorption is pretty good. I would not take more than 1 milligram at a time. Even that is about 4 times what the body produces.
Here is the link if you want to look at the whole thing:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1463812/