[bluntfang]

1 cup of black coffee has <5 cals according to the internet, not 0. it's basically 0 but i think it's important to be precise when it comes to diet.

[Someone1234]

Most sources list it as 0 or 1 calories. Additionally considering that caffeine may increase your RMR ("Resting Metabolic Rate") by 3% or more[0][1], if you want to be "precise" it may be more accurate to say that black coffee contains negative calories.

So how precise do you need it to be? 0, 1, <5, or -1, -5 calories? Or is this just pedantic nitpicking?

[0] https://www.ncbi.nlm.nih.gov/pubmed/7486839

[1] https://www.ncbi.nlm.nih.gov/pubmed/2912010

[bluntfang]

>it may be more accurate to say that black coffee contains negative calories.

Calorie has a pretty specific definition. What makes you feel like the scientific definition doesn't work for you?

[airstrike]

5 cals can really be rounded down to zero. It's important to also focus on the big picture.

[rsync]

No, actually if one is making a decision whether or not to drink black coffee while fasting, it is interesting and actionable data.

I do in fact drink black coffee in a fasted state and if it had 5 calories (which I don't believe it does) I would choose not to ...

[airstrike]

5 calories will not take your body out of its fasting state... unless you're being religious about it

[primroot]

This makes me think of premature optimization. There is such thing as energy homeostasis in biology. Most things about diet are going to be imprecise, and the target system is adapted to imprecision.