<a href="http://www.marksdailyapple.com/fasting-longevity-lifespan/">http://www.marksdailyapple.com/fasting-longevity-lifespan/</a><div><br></div><div><i>A time-honored and research-tested way to extend an animal’s lifespan is to restrict its caloric intake. Studies repeatedly confirm that if, say, a lab mouse normally gets two full bowls of lab chow a day, limiting that mouse to one and a half bowls of lab chow a day will make that mouse live longer than the mouse eating the full two bowls. Cool, cool, a longer life is great and all, but what about the downsides of straight calorie restriction, aside from willfully restricting your food intake, ignoring hunger pangs, relegating yourself to feeling discontent with meals, and counting calories and macronutrients obsessively? Are there any others? Sure:</i></div>
<div><i><br></i></div><div><i><b>Loss of muscle mass.</b> Humans undergoing calorie restriction often suffer loss of lean muscle mass and strength, all pretty objectively negative effects (unless you really go for the gaunt “Christian Bale in The Machinist” look and use a super-strong bionic exoskeleton for all your physical tasks).</i></div>
<div><i><br></i></div><div><i><b>Loss of bone mineral density.</b> Humans who calorie restrict in studies also show signs of lower bone mineral density when compared to humans who lose weight from exercise, particularly in the hip and spine – the two areas most susceptible to fall-related bone breaks. I wrote about this study some time ago here.</i></div>
<div><i><br></i></div><div><i><b>Oh, and there’s the fact that the act of restricting one’s calories can be mind-numbing, miserable, and difficult for a great many people, especially if it’s a lifelong pursuit.</b> (Unless, of course, you eat according to the Primal Blueprint and are fat-adapted. It can make CR not only tolerable, but a cinch because we become so good at living off stored body fat. We don’t suffer from sugar lows when we skip meals the way most people who fast do, but I digress.) That’s kind of a biggie.</i></div>
<div><br></div><div>...</div><div><br></div><div><i><b>Bottom line:</b> fasting may not work by some magical pathway separate from caloric restriction. It may, but it hasn’t been established. What we do know is that fasting (whether by inadvertent, enhanced calorie restriction or whatever else) improves lifespan in lab mammals and improves various health markers associated with aging and longevity in both humans and animals. <b>Fasting may not give you an immediate “Life + 25″ boost, and there haven’t been any real lifespan and fasting studies done on humans (if only we had mice-like lifespans!), but if it makes you less likely to get obese, diabetes, heart disease, or cancer, you’re less likely to die from those things.</b> The fewer things you have trying to kill you, the longer you generally live.</i></div>
<div><br></div><div>-Dave</div><div><br></div>