Definition. The urine creatinine test measures the amount of creatinine in urine. Creatinine is a breakdown product of creatine, which is an important part of muscle. Creatinine is removed from the body entirely by the kidneys. Creatinine can also be measured by a blood test.
Ketones are the byproduct of breaking fatty acids down to be burned. Okay, it's a water fast, but we can assume that after 3 days, ketosis is acheived. About 250 grams of fat is about the maximum amount of fat that will be burned daily. I say around 250-300 grams per day.
In the Induction Period, for example, amount of total fat consumed in a day comes out to 126 grams, of which the majority is monounsaturated: 55 grams to be exact. The remaining fat consists of 37grams of saturated and 21 grams of polyunsaturated. As a percentage of total fat consumed this comes out to a little less than 1/3 (30%) saturated, about 2/5 (40%) monounsaturated, and about 1/5 (22%) polyunsaturated. In Ongoing Weight Loss, the percentage of total fat from saturated fat is even less. A typical one day menu on the OWL stage has about 118 grams of total fat of which only 33 grams are saturated, making saturated fat intake 16.7% of total calories consumed for the day and considerably less than 1/3 of the total fat consumed.