population-safe intake (upper limit of the 95% CI)
...which i misunderstood as meaning the 95% confidence interval of the upper limit. that is, i thought that was a number that represented 95% certainty that you have an upper limit.
but, that didn't seem right, in the context of the actual numbers in front of me. it's a term i hadn't seen before. i found a definition at the who:
For an individual, a safe individual intake has been defined as the 97.5th percentile of the distribution of individual requirements, nominally the average + 1.96SD. Thus any individual receiving such an intake will have a very low (<2.5%) risk of deficiency (intake < requirement).
that means it's more like an ear than an upper limit, and it becomes considerably higher than i'd be able to consume. i should have also used the sigma for the specific study, rather than the one in the nap document.
from the pdf again:
Therefore, the total SAA requirements found in the present study represent the amount of dietary methionine needed to fulfill all the functions of methionine in vivo. However, it cannot be concluded from the present study whether the amount of cysteine required for the synthesis of glutathione, taurine, or sulfate was achieved with methionine intakes at the breakpoint for protein synthesis. This is an important consideration for deciding on appropriate dietary reference intakes for SAAs; additional research is required on this issue.
i had previously cited the first sentence (but had read the last one). i need to find the amount of methionine that is required for everything except cysteine, or otherwise take a guess at it.
this is confusing, but i'll get it, in the end.