This is more than a diet, and you can easily start it after reading the first few pages. The book describes intermittent fasting, and it describes in full detail the beneficial effects it can have on your body. What drew most of my attention was improved brain function. After trying it a while I discovered it really works. I sleep better and I can concentrate more at work. After my last blood work, the doctor said my blood was completely normal other than my cholesterol being too low. He cut my prescription for statins in half. Of course, my weight has fallen, too. My BMI is back under 25. This book is well documented and describes scientific studies that are complete and which ones are still underway. It does have several recipes in case you don't already know how to be prepare healthy meals, although some of the ingredients are difficult to find. You only have to partial fast two days a week. Although the author says you can eat anything else the rest of the time, you get faster results sticking to healthy meals. This really worked well for me.