Fasting is one of the oldest dietary interventions in the world, and modern science confirms it can have a profoundly beneficial influence on your health. Dr. Jason Fung, a nephrologist (kidney specialist) with a practice in Canada, has written an important landmark book on this topic.

"The Complete Guide to Fasting: Heal Your Body Through Intermittent, Alternate-Day, and Extended Fasting," co-authored with Jimmy Moore, details how to implement fasting and overcome some of the most common challenges that might arise, including persistent fears and myths associated with extended water fasting.

For the first decade of his practice, Fung was — like most doctors — conventionally oriented. As a kidney specialist, many of his patients had type 2 diabetes as the primary cause of their kidney failure.