6 cups? That doesn't sound like enough coffee to me.

Can I ask how's your sleep?

I go to bed when I am tired. Usually 11pm-1am. I fall asleep in a few minutes. Then I wake up about 7am, feeling OK. Closer to 6 hours is more normal for me.

I’ve been like that since I was a teenager and I didn't drink coffee then.

If I have to drive a long drive, as an example, I’ll skip coffee that day. I’d rather save stops.

I have the rapid variant but could not sleep well on 6 cups.

There are other genes for it too, like one that affects the degree to which coffee causes anxiety. And plenty of others that we haven't found, presumably.

So, for most people's definition of a 'cup' of coffee, they really only mean 2.5 'mugs' of coffee.

By comparison, the same 18g brewed using a pour over method should yield an 8oz cup of coffee with … likely around 170mg of caffeine.

Check out this James Hoffmann video specifically on this topic: https://youtube.com/watch?v=etnMr8oUSDo

So, "cups" for this study is whatever the respondent considers a cup. For most people, that's going to be at least 8 ounces and probably 8-12 oz.

From the full text (https://ore.exeter.ac.uk/repository/bitstream/handle/10871/1...), here's how the intake is described:

> Habitual coffee intake was self-reported as cups per day, as part of the touchscreen questionnaire at baseline with the question “How many cups of coffee do you drink a day?” (38). Participants were asked to include decaffeinated (decaf) coffee intake in their response. Decaffeinated consumers were identified from response to the question “What type of coffee do you usually drink?”. Coffee consumption was grouped in seven categories, including non- drinkers, decaffeinated coffee drinkers, and caffeinated coffee drinkers consuming <1 cup/day, 1-2 cups/day, 3-4 cups/day, 5-6 cups/day and >6 cups/day. “Coffee drinkers” in the text refer to participants who report intake of caffeinated coffee. For sensitivity analyses we constructed separate indicators restricting the data to decaffeinated coffee drinkers and according to tea consumption, using intake categories as above"

Americans will do anything to not use the metric system :)

Most people don't really care about the exact, specific volume of fluid, they just go by whatever the cup size happens to be called.

At least it is more descriptive than the grande or short cups, or the small / medium / large at other places (even if you have to know that venti is 20 in Italian to make the connection).

I stopped cold turkey for a while but nowadays have settled on more like 1-2 a day and never after a specific time of day (for me I hard stop at 3pm). Having any more than this or after this time kills my sleep immediately.