Intermittent Fasting: Shortcut to Longevity and Weight Loss?

Years ago I wrote a post about intermittent fasting.  It sounded like an intriguing but no-way-in-hell-am-I-ever-gonna try it approach to tweaking one's calorie consumption, improving health, and perhaps even increasing longevity.

Sort of like the idea of trying to turn myself into a brown-fat packin', calorie-incinerating superhuman by bathing in ice water: The results sound fun, but: Ain't gonna happen!

I like to eat every day! And I complain about how cold the water is in freakin' Hawaii, of all places. No matter how miraculous some body-hacking shortcuts claim to be, they have little appeal to me if they involve more than a trivial amount of discomfort.

But then I kept reading more about the shorter, easier versions of Intermittent Fasting.  The notion that if one restricts daily eating to a shorter window, say of 8 hours, that it could lead to beneficial changes like weight loss, "fat-adaptation," and even lower the risk of Alzheimers.

The "16-8" program worked for Hugh Jackman apparently:

(Please don't sue me, 20th Century Fox!
CC search said "labelled for reuse" but I'm skeptical).

Could it also work for Crabby McSlacker?

Well, I did some experimenting for a number of weeks and thought it might be time to share the shocking results!

First some background:

Why Fast?

There is a lot of interesting research on intermittent fasting, and a boatload of possible health benefits.

Mark's Daily Apple has collected a lot of information, and there is a multi-part series beginning with this post on fasting and weightloss.  The series includes a handy breakdown of several fasting methods like alternate day fasting, the 20-4 Warrior approach and the kind I tried, the 16-8. And another post of his lists a whole bunch of IF health benefits including "increased longevity, neuroprotection, increased insulin sensitivity, stronger resistance to stress, some cool effects on endogenous hormone production, increased mental clarity, plus more." (Many more. A staggering list is in that post, actually, if his research is all valid).

Charlotte at The Great Fitness Experiment fasts for religious reasons, and has a good roundup of fasting benefits over at her place too.

For me personally, I was intrigued because while I generally eat a healthy diet and get plenty of exercise, since my hysterectomy I'd been starting to gain a bit of weight.  And I gain weight as visceral belly fat: this is not good.

My father and maternal grandparents all died in their early fifties of cardiovascular and other diseases (my age now), and my cholesterol and blood sugar levels have been starting to creep up into Watch Out zones despite all the f--cking kale and salmon I eat and the HIIT etc that I put myself through.  So there is a health component to my ongoing desire to banish that belly fat, not just vanity.

Though hell, I'm human: vanity figures in too.  Leave me alone, stupid belly fat!

So I'd been tempted to see if IF might the secret weapon I'd been looking for, as magic pills have not yet been invented.

However... a few caveats...

Fasting Length

I should to do more research on this, and if anyone has some handy references I'd love to edit this post to include them, but my half-assed take on it is that most of the research on the benefits of IF come from longer fasting periods, like a whole day at a time, not the wussier "eating window" approaches.

However, these "eating window" plans have a lot of support, and I was too lazy to scour the studies and see which if any were talking about 8 hour windows, which is pretty much the least intense variety proposed and the only one I'd be willing to put up with.


It also looks like women respond differently, and generally not as well to IF. Lots of info to read through if you are a woman contemplating this approach over at  Paleo for Women post on Intermittent Fasting.  For example, in one of the studies cited by Mark initially as touting the beneficial metabolic changes from IF, it turns out that was only for male fasters, not the gals. In fact according to the Paleo for Women post:
 a) women in studies covered by the review did not experience increased insulin sensitivity with IF regimes and b) women actually experienced a decrease in glucose tolerance. These two phenomena mean that women’s metabolisms suffered from IF.
Because of concerns like these, Mark tweaked a bit and has a follow up post on Women and IF.

But, this didn't mean there were no benefits for women, but there were hormonal complications and complexities about which women should be aware.

Another Complication to 8-16: Meal Timing?

Around the interwebs, many intermittent fasters were reporting great results with 8-16 sort of plans. And while some ate early and ended their eating windows in the afternoon, many more were starting to eat later in the day, say about noon or even 2pm.

This intrigued me. I look forward to dinner all day long, so there was no way I was gonna skip that.  Hearing that people were reporting weight loss and improved blood panels and energy etc even with these afternoon/evening eating windows sounded like excellent news. 

But wait... in the Holy Book of Healthy Living, wasn't there a commandment handed down about this?


Isn't there plenty of research saying you should force feed yourself first thing in the morning even if you're not hungry because breakfast eating is highly correlated with lower body weight even if it seems odd that skipping a meal would result in more weight gain, not less?

Well, the smart scientists behind The Alzheimer's Diet, who are proponents of the health benefits of mild ketosis in the mornings, said they didn't think the evidence was all that convincing on that point.

And I saw some hopeful research about the fat-burning effects of a fasted morning workout. Though again, done on just men.

On the other hand it does seem like the meal timing and anti-breakfast skipping studies keep popping up too, like: early eaters lose more weight than late eaters; skipping breakfast may raise risk of diabetes, blah blah blah blah.

And, a post-publication update: another study, again just on MEN damnit, says:  skipping breakfast may increase coronary heart disease risk.

Cheaters Never Prosper?

Another thing that made the experiment it appealing was there was a slight "cheat" factor; many proponents of the 16-8 that I was contemplating say you can maintain the desired state of mild ketosis while still adding a splash of cream in your coffee or drinking meat broth.  Again, is there any extensive clinical research on this?  I was mostly in anecdotal territory, but if true, this seemed like it would make things a little easier.

Anyway, armed with a bunch of conflicting and confusing information and high hopes, I decided to give it a shot.

My Intermittent Fasting Experiment Protocol

Here's what I did:

1.  I did not fork over for a book or program like Leangains or the 8-hour Diet book or other official thing.  I just checked in with a few blogs, some I respect and some I'd never heard of. So my results do not reflect on anything other than my own experiment.

2. Official Feeding Time was a 6-8 hour window starting around 11am-noon; ending at 6-7. I generally get up at 5 or 5:30am and go to bed around 9ish, so for me, this is indeed a "late" window.

3.  For the last 2-4 hours of the fast, I took advantage the cheaty "cream splash/broth" loophole that some guidelines allowed for. For me, it was a few tablespoons of unsweetened coconut milk beverage (SoyDelicious at 45 calorie per cup) and some stevia in my coffee and tea; I also permitted myself a cup of no-carb low cal chicken broth.  Total "cheat" calories during the last few hours of fasting were no more than 10 per hour and no more than 30 total.

4.  I did my normal strength training and cardio and HIIT workouts in a fasted state.

5.  I tried not to be a total insane disgusting slobbering pig during the feeding period.

6.  I totally confounded the experimental variables by simultaneously further reducing carbs in my diet.  I was smitten with the notion of becoming "fat adapted" and thought the combo approach might be most effective.

7. I conducted the experiment for about 3 months.

8. I was too cheap to spring for blood tests, and decided if it became a way of life I'd check in at my next physical and hope for awesome numbers.


1.  Compliance Was Way Easier Than I Thought!

I actually loved this approach to reigning in my intake.  I suck at portion control.  The on/off nature of the plan felt very freeing.  I felt either Virtuous or Entitled, depending on the time of day, as these are two psychological states I'm very fond of.

Of course, I picked the easiest plan and allowed myself the cheat beverages, which made a huge difference in not feeling deprived.

I think it took a few workouts to feel "normal" but I adapted.  I had lots of energy throughout the day.

I did not find myself totally gorging during eating windows, but I really enjoyed the sense that I could be more liberal with food choices.

I found it much easier to curtail my overall calorie intake and in fact ended up most days well below the number of calories I usually target when I bother to count.

2.  But Something Screwy Happened to My Metabolism!

After I lost an initial three pounds, probably mostly water, there was virtually no more gradual weight loss--even though I had reduced calories to levels well below what should have resulted in further decline.

The apparent slowing of my metabolism, negating all my virtuous not-eating, grew more and more discouraging.  I grew impatient.  Why was my belly fat not getting the hint?

 Cranky Cat by Reb

And finally, I said F--k it.


So yeah, a 16-8 plan didn't seem to work to help me lose my visceral fat, which was my prime motivator. I guess everyone is different. It is possible I didn't try it for long enough, or I needed to skip those morning beverages after all, or choose a smaller eating window, or shift to an alternate day eating plan.

But I wasn't willing to do any of those things. For me, it appears that a more old school eating plan that includes morning meals, and more attention to portion control throughout the day rather than the on/off approach gets me better results.


What about you guys, have you or would you try intermittent fasting? Any other weird eating experiments you've tried?

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