Re: What are typical ketone levels during an extended fast?

DesertLily, you peaked my curiosity. A web search finds that, yes, there is a test for calcium in urine (24 hour collection sample), and yes, the kidneys do excrete calcium to some extent. Whether this daily loss is much or little I don't know, but it means that there is going to be at least some bone loss over time. Another concern is that high levels of calcium in the blood promote kidney stones, but a fast lasting no more than a few weeks might not be long enough to cause them. At age 70 I am maybe more concerned about bone loss than someone younger. Of course, I expect the calcium to be restored now that the fast is over. Eat lots of oranges and green leaves.