Title says it all. Assume this is production above and beyond normal, such as when giving blood. I didn’t want to google this because the issue might be confused with how many calories are in a pint of blood, which is a different issue.
About six hundred.
From this thread:
ETA: Sorry, I now realize you wanted “expend to create” not “in”. Well, still interesting. Maybe?
Although it varies quite a bit, a rule of thumb is that growth efficiency in most organisms is around 10%. If a pint of blood has about 600 calories, it would take on the order of 6000 calories to produce it. This is a pretty rough estimate, but it looks like a pint of blood represents about 1-3 days of food intake.
I’d be very interested to know just how wrong or right I am.