[maxxxxx]

I don't know. When I drink more than 2 cups my sleep suffers and even my personality changes. I get pretty hyper and less patient. With my girlfriend I can tell immediately whether she has had coffee just from the way she talks.

[toomuchtodo]

Try to cut off the caffeine consumption by 3pm and your sleep should not suffer (based on the half life of caffeine and average human adult body weight).

Disclaimer: I consume ~4 cups of coffee per day between 8am and 3pm and get ~8 hours of sleep per night.

[enthalpyx]

The CYP1A2 gene affects how quickly you metabolize caffeine. Stopping at 3pm may not be enough.

[toomuchtodo]

I’ll check my CYP1A2 SNPs on 23andme in the AM and report back.

[35bge57dtjku]

I'm not sure if that's sarcasm or not. Maybe I'm just not hip.

[toomuchtodo]

Not sarcasm at all. Last time I checked, 23andme reports if you’re a fast or slow caffeine metabolizer. I just don’t recall offhand which I am.

[notlob]

Why would that be informative? It doesn’t tell you your protein expression levels nor effective enzymatic activity.

[jacalata]

You don't know what - if this general result could be invalidated by your personal experience not matching it?