Those of you who've been part of the CR Society for a long time will certainly remember Warren Taylor. Warren was a very active member of the CR Society in the early/mid 2000s and one of its biggest proponents. He's a very kind and gentle man, known for some rather extreme perspectives and practices. I just heard from Warren and he was happy to share his CR story so that others might learn from his experiences. It's a cautionary tale warning about the dangers of inadequate nutrition, not tracking health markers carefully, and taking CR too far. It is the kind of candid information sharing we need to understand the risks, as well as the benefits of CR and the different ways of practicing it.   Here is Warren's story in his own words:   As for me, I am 70 years old this year. I’ve almost totally defeated my osteoporosis with extra calories and lots of daily walking. For my next DEXA scan, I hope to show no osteopenia. That will mean I have no comorbidities. Zero. I did have Gleason grade 7 prostate cancer laparoscopic surgery in 2008, about 7 years ago. I am formally cancer free (malignancy totally self-contained within the prostatic fascia).   However, I do take daily baby aspirin (started in Apr 2012) to protect against possible cancer metastasis.   [information about baby aspirin benefits snipped for brevity - DP]   I do continue to do quite a bit of research into classical allopathic medicine. All of my blood tests are within normal bounds now, so I am not very much calorie restricted at present, with a BMI between 22 to 24, depending on whether you take my original height (66 inches) or current height (63 inches), my having lost 3 inches over the past 10 years.   I’m not really much excited about CR any more, due to the way I have seen practitioners skip medical testing, with some of them severely restricted, with little or no medical testing (esp skipping DEXA scans, and failing to track bone density over the years). I did suffer a whole flock of hairline rib fractures back about 12 years, which were so crippling and painful, that I could not gamble with bone health any more.   I do know how to compute the expected bone density loss/gain for both hip and spine as a function of age for men. Over a given period of time, one can just multiply the rates for each year. Attached JPG file:   Rate of Change of Bone Mineral Density as a Function of Age in Men (1660.full.pdf) Figure 3 -- 20150624.JPG   Website:   In my own case, at least four things were amiss simultaneously, which happened PRIOR TO MY CR (~1990 to 1995):   1) 5 years -- Absolutely no sunshine and no Vit-D supplements!   2) 5 years -- Strict vegan only (no animal protein whatsoever)!   3) 5 years -- Veggie protein malnutrition (LAIAA principle)   4) 5 years -- Excessive exercise.     In my case, DURING MY CR (~1997 to 2007), at least 5 things were wrong:   1) 10 years -- Greatly inadequate protein intake   a. I measured grams of protein as grams of chicken, fish, etc. (60 g/day/kg)   b. Misunderstanding that grams of chicken, fish, etc is NOT grams protein.   c. Failure to understand that high protein foods are 80% to 90% WATER.   2) 10 years -- Inadequate caloric intake, continual Low body weight, continual weight loss.   3) Lack of exercise (to reduce caloric intake, and unable to exercise).   4) Poor, low BMI (reduced to BMI = 18)   5) Foolish delight in abnormal medical test parameters (out-of-bounds).   As a result of my extreme CR, I began to suffer poor peripheral circulation, with painful varicose veins (spider veins) and blood leakage into my feet and and ankles, which turned blue and black. It has taken years to recover from this.   I do feel much better now in 2015 (2008 to 2015), with much improved circulation, and DEXA scan results with non-osteoporotic readings --- and approaching the barely osteopenia borderline. It has taken 8 years to reach recovery levels, and much hard work and patience doing extensive walking (and some running).   One turning point was discovery that all of my CR work had NOT prevented prostate cancer --- even though my PSA was normal --- NOT elevated. And the physical trauma of cancer surgery blatantly attested to me that severe CR is very dangerous, with great difficulty (many months) trying to recover after surgery, with little body fat on my skinny frame. Recovery was very slow and painful, even with relatively benign laparoscopic surgery.   That is a quick summary --- probably more than you would ever want to know!   --- Warren