I take it in the morning just because I found that taking it late at night harmed my sleep. I have no idea how much people taking it later in the day might reduce benefits by damaging sleep; I would guess that the elderly people usually enrolled in these trials would be taking it as part of their breakfast regimen of pills/prescriptions and so the underestimate of benefits is not that serious.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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