Monday, May 31, 2010


Here is the latest bit of wisdom from Mark Sisson, author of the book The Primal Blueprint and Mark's Daily Apple website.  I have been doing Intermittent Fasting (IF) for over two week now, and I am seeing benefits.  What I usually do is eat a hearty, fat rich breakfast and then fast until evening dinner.  I get just a little hungry in midday, but it's nothing I can't live with, and the benefits outweigh that little pang, in my opinion.  Read why Mark thinks this is a good and scientifically valid idea:

Drop that fork (or pair of chopsticks, or piece of meat, or handful of nuts) and pay attention. Today, you're going to skip your next meal. Skip your next two, if you want, but make sure you at least miss the next meal. Consider this a Primal Directive, the nudge in the right direction toward Intermittent Fasting that you've probably been mulling over but have yet to fully embrace. I talk about it enough in the blog, but actually fasting can be a difficult thing to try. For one, food is awesome. Food tastes good, especially good Primal food. It's natural to want to eat it, but it's also natural to avoid it for relatively long stretches of time in order to capitalize on the metabolic benefits
In an evolutionary context, the idea that there are benefits to fasting makes perfect sense. Grok experienced times of plenty and times of scarcity. Sometimes the hunt didn't go well. Sometimes he might only get one big meal in a two-day span of time. Now, conventional nutrition "experts" would suggest that a fasting Grok would experience a slowed metabolism, cannibalized lean body mass, and increased body fat. But would that make evolutionary sense? Why would our bodies develop a response to scarcity that promoted physical infirmity, weakness, and decreased mobility? If we were without food, wouldn't it make sense for our bodies to conserve strength and burn fat for energy, rather than reduce it and burn muscle? In a tight spot like possible starvation, we needed that strength more than ever. And so, on a purely theoretical, logical level, the Conventional Dietary Wisdom regarding skipping meals doesn't add up.

The actual research tells a different story, too. In past MDA posts like this one, this one, and this one, I touched on some of the science behind Intermittent Fasting. There have been some pretty comprehensive reports on fasting, including this one which looked at a variety of animal and human studies and found it improved insulin sensitivity and glucose uptake (important for fat loss), increased resistance to lipid oxidation damage, and ! it incre ased fat loss, while providing protection for certain diseases. Another study noticed that fasting significantly increased longevity in rats. We aren't rats, but we are mammals, and several other studies suggest similar benefits in fasting mammals, including this one that looked at the effects of Intermittent Fasting on elderly, otherwise healthy hominids; Dr. Eades discussed the same study some time ago, noting that the fasting scientists experienced "health benefits... in insulin resistance, asthma, seasonal allergies, infectious diseases of viral, bacterial and fungal origin (viral URI, recurrent bacterial tonsillitis, chronic sinusitis, periodontal disease), autoimmune disorder (rheumatoid arthritis), osteoarthritis, symptoms due to CNS inflammatory lesions (Tourette's, Meniere's) cardiac arrhythmias (PVCs, atrial fibrillation), menopause related hot flashes." Quite a laundry list, and it's largely anecdotal, but interesting nonetheless.

Of course, just skipping a single meal won't result in all the benefits of fasting, but it will get you on the right track. Consider this an order, rather than a tip. Skip your next meal, no questions asked. If you feel okay, skip two. Hopefully, you can use this as motivation to more fully explore the world of IF. Once you're on board, I'd check out LifeSpotlight for a fantastic primer on fasting, or you could browse my "How-To IF" post. Both will help you integrate fasting into your lifestyle.

To sum up, if you're interested in the following...

  • Mobilization of adipose tissue for energy (burning body fat as fuel)
  • Improved insulin sensitivity and glucose uptake (again, good for burning body fat)
  • Increased resistance to oxidation damage to lipids
  • Increased human growth hormone secretion (utilizes body fat for energy while preventing protein/muscle catabolism)

No comments:

Post a Comment