We at Cranky Fitness endeavor to stay at the cutting edge of nutrition and health reporting, except when we can't be bothered.
But we can't help noticing that Intermittent Fasting is becoming a hot topic. So it seems a good time to
So here is it is: a Cranky Fitness Q & A, telling you Everything You Ever Wanted to Know About Intermittent Fasting, Unless It's Kind Of A Hard Question.
Q: What is Intermittent Fasting?
A: "Intermittent Fasting" means: Not Eating (yikes!)-- But Only Sometimes (whew!)
Q: Sounds Unpleasant. Why in the World Would I Want to Do That?
A: Because research suggests that intermittent fasting may have health benefits. This seems to be true even if you go back and scarf up all the calories you missed out on once you go back to eating. And this technique works particularly well if you're a mouse! (Most of the studies are still animal-based).
Also, there is plenty of research suggesting that people on long-term calorie restricted diets see improvements in health and longevity. But then who wants to face the prospect of nearly starving yourself every day for the rest of your very long, long, long, long life? Intermittent Fasting is, at least theoretically, a way to get some of those Calorie Restriction benefits while still getting to pig out every now and then.
Two good but somewhat conflicting sources of information on this are: Mark's Daily Apple, which gives handy and rather optimistic suggestions on how to do IF, and an article by Alan Aragon, who has brought together a lot of research on the subject and is perhaps not quite so optimistic.
(Note: we love Mark's Daily Apple, but they are much more Hardcore Healthy over there than we are, so we shall be poking gratuitous fun at them. They are always so darn cheerful about eating their junkfood-free diets. Where's the whining? Anyway, Mark fans, be forewarned).
Q: What Are Some of these Great Health Benefits From Fasting?
A: Glad you asked! If the animal stuff proves out in humans, some of the benefits could include: "decreases in blood pressure, reduction in oxidative damage to lipids, protein and DNA, improvement in insulin sensitivity and glucose uptake, as well as decreases in fat mass." (Note: summary stolen word for word from Mark. Why waste good summarizing?)
Q: Sounds Cool! So How Much Not-Eating Will I Have to Do?
A: Here's where it gets complicated. There seems to be two ways of looking at it.
The Easy Way:
This is the approach taken by the folks at Marks Daily Apple. Basically, they say: don't eat whenever you don't feel like eating. You don't have to go a whole day without eating, because, well, I don't know why not.
Along with more difficult options, they suggest the "condensed eating window," the "early and late" plan, and the "skipped meal." (They also suggest elsewhere on the blog that you should generally be trying to fuel yourself by grazing throughout the day, eating frequent meals to keep your metabolism moving. So as far as I can make out, if you're eating frequently or not eating at all, it's all good. Or all bad--it depends on your general tendency towards either smugness or guilt).
But Mark isn't the only one who suggests that skipping even single meals might bring health benefits. He's got Mark Mattson, a neuroscientist, on his side. And we hate to argue with neuroscientists because who knows, one day they might do something sneaky to our brains when we're not paying attention.
Q: So What's Wrong with Doing it The Easy Way?
A: Well, a quick glance at both the human and animals research seems to indicate a mysterious leap from studies looking at "Alternate Day" fasting to recommendations that one try "Intermittent Fasting" and skip a meal here and there. The studies that look impressive tend to be "Alternate Day" regimens that involve fasting or drastically reduced eating (i.e. 300 calories total) for an entire day, not just missing a meal now and then.
In fact, research suggests that "haphazard eating" isn't smart and that eating just one meal a day has some health downsides.
On the other hand, research for this blog post was not exactly exhaustive. (Hello, Google? Got anything on intermittent fasting?) So if anyone knows of a good study showing awesome health benefits from skipping random meals, please pass it on.
Q: Okay, So Should I Try Alternate-Day Fasting Then?
A: Sure! But watch out:
Most people who do it get really hungry.
On the other hand, many of us know people who fast periodically or who eat just one meal a day and they seem to be totally fine with it. (Weak-willed cupcake-consuming slackers like Yours Truly are not among them).
Q: This is Too Confusing! Maybe I Should Just Go Back to the Idea of Fueling My Metabolism by Eating Small Frequent Meals All Day Long?
A: Errr... maybe not!
Weirdly enough, given how many times we hear this "fueling" suggestion, according to the Aragon article there's not really much research to back it up. It looks like folks may be overgeneralizing from the Don't Skip Breakfast research. (Don't Skip Breakfast is indeed well-supported. So we're with your mother on this: don't even think about it).
Q: So then What Do You Suggest?
A: Don't skip breakfast. But then after that, do whatever the hell you want. Keep an eye on the research--or better yet, stay tuned to Cranky Fitness. If the studies get more definitive about when you should eat and when you shouldn't for optimal health, we'll let you know. That is, if we happen to be paying attention that week.
Q: Were You Aware That Reading About People Not Eating Can Make You Really Really Hungry?
A: Yes, this phenomenon has recently come to our attention! However, research indicates that a peanut butter and banana sandwich with a glass of milk will take care of the problem fairly quickly.
So have any of you folks tried fasting?
Or are you thinking about it? Cranky Fitness is too attached to frequent meals to even attempt an experiment, but we'd love to hear your thoughts or experiences.
And On an Unrelated Note:
Tomorrow is a special day for Cranky Fitness. If you're Smart Enough to figure out why, don't give it away just yet--instead, be sure to check in tomorrow for a Very Special Post!