One way to know if you are actually making progress towards better health with intermittent fasting is from the information contained in blood tests and cholesterol panel numbers. Unfortunately interpreting them can be complicated and tedious. There is however a simple (and free) cholesterol panel ratio that will identify your level of risk of cardiovascular disease (CVD), small LDL particle size and insulin resistance.

Paraphrasing: Volek / Phinney's book "The Art and Science of Low Carbohydrate Living", page 95:

"... the ratio of you triglyceride to HDL-C is an effective surrogate for LDL particle size. Values of TG/HDL-C over 3.5 indicate that you probably have ... a predominance of small LDL particles, and a ratio this high indicates there's a good chance you have also have insulin resistance."

which references the following study:

"Is there a simple way to identify insulin-resistant individuals at increased risk of cardiovascular disease?" http://www.ncbi.nlm.nih.gov/pubmed/16054467

Also, for those less-inclined to struggle with medical terminology, I suggest one (or both) of these explanatory articles:

http://www.docsopinion.com/2014/07/17/t ... hdl-ratio/

http://www.lef.org/magazine/mag2006/may ... art_02.htm

Enjoy

Update edit: April 25, 2015 to replace broken second link. New link has useful conversions for European/Canadian/US measurement systems.