Fasting- is it about calorie restriction or insulin resistance?

This topic contains 5 replies, has 3 voices, and was last updated by NofOne 9 years, 5 months ago.

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fitnfast

8:39 am
3 Jul 15
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As I begin to write this post, I already know that it will spark some criticism! And that’s ok. Healthy disagreement and .mutually respective arguments make for a lively discussion!

So, anyway, reading through the posts every morning, I see most people talk about how many calories they did or didn’t eat, etc. Which is all fine. 5:2 is a great plan and has changed the lives of many, myself included. But after reading the book, and many books and blogs since then, it is my understanding and belief, that fasting IS NOT about calorie restriction at all.

Fasting is designed to lower the body’s insulin levels. Insulin is the hormone that tells your body to STORE fat. Every time you eat, especially processed carbs, and to a lesser extent, protein, your insulin level rises, and you store it as fat. When you fast, or when you eat healthy fats, your insulin drops, and after a certain period of time in this state, your body has to use that existing stored fat to operate.

So lowering the amount of calories you eat isn’t as important, IN MY RESEARCHED OPINION, as what kind of foods you eat, and how long you fast.

Again, I know I am inviting the wolves to pounce upon my head and gleefully jump up and down on it, but I rely wanted to put this out there.

Two great sources for the science of insulin resistance and fasting is:
http://www.intensivedietarymanagement.com
And
“Good calories, Bad calories”, by Gary Taubes.

HappyNow

10:32 pm
3 Jul 15
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Hi Fit,

I’m not a wolf! And it’s been hours since you posted and no one’s jumped on you yet…! They must be offline 🙂

I think you raise valid and interesting points.

From what I’ve read (and I admit that’s not everything!), a lot of studies seen to involve both extended (i.e. longer than 11pm-7am) fasting and calorie restriction. I’m not sure how the two can be teased apart, and perhaps they are additive.

In terms of weight loss (and maintenance), I know some say it doesn’t matter when you consume your calories (or what you consume). That may well be the case under controlled laboratory conditions. But here in the real world the anecdotal evidence appears to suggest that is not in fact the case.

I’m an advocate of 16:8 and low/no processed white carbs/ sugar (weekends excepted). I’ve been mostly maintaining my weight that way for a year now. I very rarely do a ‘5:2/6:1’ fast these days because I lose 0.5kg each time. Which of course doesn’t add up according to the maths (46 yr old woman, 59kg, 5ft7). At most I’d be creating a calorie deficit of perhaps 1400 calories which does not equal 1lb. So in my mind, calorie restriction + longer fasting windows + low processed carb/ added sugar adds up to more than the sum of it’s parts. For me at least.

NofOne

7:28 am
4 Jul 15
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@happynow, the 0.5 kg is largely the depletion of stored glycogen. For every four calories of stored glycogen burned during your fast day, that’s 5 grams; one of glycogen plus the 4 grams of water required to store it. Virtually all of it will return as soon as you eat some carbohydrates and drink a bit of water. (I’m assuming you’re not on a nutritionally ketotic diet most of the time.)

@fitnfast, I think that you are exactly right regarding the calorie restriction. I read a lot of posts where people claim to be combining 5:2 with severe caloric restriction on their non-fast days. I’ve seen several, and responded to one, where posters have detailed eating plans that worked out to a daily average across a week of ~1,000 calories/day. I fear that these people are sacrificing the benefits of intermittent fasting suggested by Dr. Varady’s research on ADF. I can’t see why the caloric restriction combined with 5:2 or ADF shouldn’t be just as harmful and, in the long run, counterproductive as the garden variety eat-less-exercise-more diets have proven to be. (Anyone interested in the details of this should read Traci Mann’s excellent book, “Secrets from the Eating Lab: The Science of Weight Loss, the Myth of Willpower, and Why You Should Never Diet Again”, http://www.amazon.com/Secrets-Eating-Lab-Science-Willpower/dp/0062329235)

fitnfast

8:39 am
4 Jul 15
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Thank you both for your replies! I guess the wolves are busy chewing on other bones!

I also was doing 16:8, and just started to play with 19:5. I do try to eat a keto as possible, but I haven’t counted calories in months. I suck at it anyways! The fasting is what torches off the fat (and water, as you say, goes right along with it.)

Nof One, you sound like you really know the body well. And thanks for the book recommendation. Will look that one up! I just hope some people read this and understand better how much more difficult they are making it.

HappyNow

10:25 pm
4 Jul 15
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NofOne,

You misunderstand me.

The 0.5kg loss I refer to is not what I record the morning after the fast, it is a consolidated loss on the days following the fast.

Perhaps an example will better explain.

The week before last I was 60kg ish every morning. That’s the upper limit I set on maintenance, so I decided to fast last Monday.

On Monday morning I was 60.4, part of that being increased water retention as a result of white bread, rice and pizza at the weekend.

On Tuesday morning, post fast (500 cals, all consumed during the evening), I weighed 59.1 (i.e. 1.3kg less than the day before, obviously some water loss and less food in transit).

I ate normally for the rest of the week, and my Friday and Saturday morning weight was 59.4, i.e. roughly 0.5kg less than the week before.

And no, I’m not on a ketogenic diet. But I mostly don’t eat white bread/ pasta/ rice or added sugar on week days. They’re weekend ‘treats’, although obviously that’s an oxymoron 🙂

This has been the case for over a year now. My weight is pretty steady. If I fast I lose 0.5kg. I’ve actually been working on overeating so I can gain enough weight to fast for health benefits.

NofOne

2:51 am
5 Jul 15
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@happynow, you are right, I did misunderstand what you were trying to say. As for the a-calorie-is-a-calorie, or it’s common variant, calories-in-calories-out, I think they can be safely dismissed. I wouldn’t argue with anyone asserting it. I would just take it as an indicator of people who I’d be better off not engaging with.

While we’re on book recommendations, I’m starting to read up on the two books by John “Kiefer” Kiefer, The Carb Nite Solution, and Carb Backloading. Kiefer’s not a doctor or a nutritionist, he’s a bodybuilder, but… “He has a Master’s degree…in science!” (Whatever happened to Ask Dr. Science? Is that still a thing?) Anyway, Kiefer has some interesting hypotheses about macro-nutrients, and cyclical patterns in the endocrine system. It’s a shame that he doesn’t have access to real data, or a lab to test his ideas. Still fun to think about the possibilities.