Beyond The 120 Year Diet : How to Double Your Vital Years, published in 2000, is the follow-up to CR guru Roy Walfords's classic, The 120 Year Diet. In layperson's terms, Walford describes how and (theoretically) why CR works. Apart from being and excellent and well-referenced science book, it is a manual for human CR. Here are some of the many subjects discussed:

--Biomarkers of aging, and tests you can do on yourself.

--The concept of nutrient density.

--How to lose weight.

--Fasting.

--The nature of evidence.

--Interacting with your chosen physician.

--Prevent what is going to kill you.

--A lesson from Biosphere 2.

--The complex philosophy of supplementation.

--Exercise, stretching, and the maladies of wear and tear.

--Recipes.

--Dining out.

--Chart: Nutritive values of the best foods.

This book is frequently cited by many CR Society members and can be considered -- for now, anyway -- the "bible" for practicing human CR.