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Intermittent fasting 2 days vs. 1 day per week

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Re: Intermittent fasting 2 days vs. 1 day per week

#21

Post by bena »

daviross wrote: post #14

> protein pacing diet for the remaining five/six days/week (Protein pacing refers to 4–6 meals/day evenly-spaced, where each meal contains 25–40g of protein) > During fasting days, participants fasting for one day/week were allowed to consume 400 Kcal/day, while participants fasting for two consecutive days were allowed 500 Kcal/day. During non-fasting days the dietary regimen provided 1350 and 1700 kcals/day for wom…

Assuming 2000 kcal/day is the normal amount blah blah blah.

For men, they are running a 300 kcal deficit for 5 days and 1500 kcal deficit for the other two. For a total of 4500 kcal per week. Or losing about a pound and a half.

Now, seeing as this is for overweight people, it's likely to be even more. As it takes more calories per day to maintain higher weights. So if the person's maintenance is about 3000 kcal/day, that's going to be a deficit of roughly 11,500 kcal per week. Which is close to 4 pounds.

But then again, restricting yourself to just 2000 kcal/day would have you lose about a pound and a half per week.

Because, when you are very overweight, lots of things work.

Re: Intermittent fasting 2 days vs. 1 day per week

#22

Post by FartyMcFarter »

hackerlight wrote: post #19
leereeves wrote: post #2

> Protein pacing refers to 4–6 meals/day evenly-spaced, where each meal contains 25–40g of protein That's a lot of protein, comparable to the amount that bodybuilders consume. Does fasting increase protein requirements?

Minimum for normal people should be 0.8*kg/day and muscle building gains top out at around 1.6*kg/day. If these people are fat then just 1.0*kg/day could be 125g/day.

> If these people are fat

I've always wondered - do the 0.8 / 1.6 grams of protein per kg apply equally across someone's whole weight? If someone has a lot of body fat compared to lean mass (bones / muscle etc), would the protein requirement per kg go down accordingly?

In other words, does having more fat tissue increase protein requirements, or should we instead think of protein requirements only for lean body mass?

Re: Intermittent fasting 2 days vs. 1 day per week

#23

Post by cecilpl2 »

chasebank wrote: post #3

Having water fasted many times, I swear this has something to do with burning all the stored glycogen. I have no backing other than what I’ve experienced myself. I get really hungry for a week after a fast and continue to lose weight or stay the same. Anecdotally, I’ve chalked this up to as long as your glycogen bank isn’t full, you can pretty much eat whatever you want. Water fasting is glorious btw.

To add some numbers - your liver and muscles store about 500g or 2000 calories of glycogen. Each gram of stored glycogen is bound to 4 grams of water, for a total of roughly 2.5kg / 5lbs of weight.

When you eat in a calorie surplus, your glycogen stores are full. When you eat in a sustained deficit, you operate with very low glycogen stores.

This is why when you start a diet you often immediately lose 5 pounds in the first few days.

This is also why when you are dieting and have a huge cheat meal, you "gain 5 pounds" and then lose it again immediately upon resuming your diet. It's mostly retained water since your body converts the giant influx of calories into glycogen then burns it off over the next several days.

Re: Intermittent fasting 2 days vs. 1 day per week

#25

Post by bhaney »

> Given the same energy intake

> During fasting days, participants fasting for one day/week were allowed to consume 400 Kcal/day, while participants fasting for two consecutive days were allowed 500 Kcal/day. During non-fasting days the dietary regimen provided 1350 and 1700 kcals/day for women and men, respectively

That seems like the first claim is just untrue and the 2-day-fasters are consuming fewer calories overall? If all the non-fasting days are the same for both groups like this says, then the 2-day-fasting men are consuming 1100 fewer calories per week (and 750 fewer for women). Even if intermittent fasting did nothing at all, I would expect that extra calorie deficit to result in more weight loss.

Re: Intermittent fasting 2 days vs. 1 day per week

#26

Post by happyopossum »

hackerlight wrote: post #19
leereeves wrote: post #2

> Protein pacing refers to 4–6 meals/day evenly-spaced, where each meal contains 25–40g of protein That's a lot of protein, comparable to the amount that bodybuilders consume. Does fasting increase protein requirements?

Minimum for normal people should be 0.8*kg/day and muscle building gains top out at around 1.6*kg/day. If these people are fat then just 1.0*kg/day could be 125g/day.

They targeted a BMI > 27.5, which could be ‘fat’ or it could be ‘a little soft’, or it could be someone who’s really swole.

For reference a 27.5 BMI is 5’9” at 186lbs. I can attest that when I’m well muscled, nobody thinks I’m fat at 186, but when I’m not yolked, I look like a tad doughy.

The average adult male in the US has a BMI of 26.6 btw…

Re: Intermittent fasting 2 days vs. 1 day per week

#27

Post by saargrin »

daviross wrote: post #14

> protein pacing diet for the remaining five/six days/week (Protein pacing refers to 4–6 meals/day evenly-spaced, where each meal contains 25–40g of protein) > During fasting days, participants fasting for one day/week were allowed to consume 400 Kcal/day, while participants fasting for two consecutive days were allowed 500 Kcal/day. During non-fasting days the dietary regimen provided 1350 and 1700 kcals/day for wom…

1700 kcal a day for male is already pretty high calorie deficit even without any physical activity

Re: Intermittent fasting 2 days vs. 1 day per week

#28

Post by DoreenMichele »

The reason why intermittent fasting works is that it is associated with increased oxidation of fatty acids (lipolysis) and ketone body formation (ketogenesis), activated cell-signaling pathways (insulin sensitivity, reduced inflammation, autophagy), and preservation of lean body mass, known as “metabolic switching”.

The interesting fact however is that typically, these mechanisms are not fully activated until at least 24 hours of fasting.

Well, this sounds to me like they know it has an effect but they don't actually know the full story on why it works.

Re: Intermittent fasting 2 days vs. 1 day per week

#29

Post by chasebank »

A4ET8a8uTh0 wrote: post #11
chasebank wrote: post #3

Having water fasted many times, I swear this has something to do with burning all the stored glycogen. I have no backing other than what I’ve experienced myself. I get really hungry for a week after a fast and continue to lose weight or stay the same. Anecdotally, I’ve chalked this up to as long as your glycogen bank isn’t full, you can pretty much eat whatever you want. Water fasting is glorious btw.

Could you elaborate a little about your regimen? Each time I attempted water fasting, the next day I was basically famished ( and needless to say, any progress made was lost ).

I would drink water for 5 days. It's not too difficult. The hardest part is the boredom. I'm quickly reminded how much of my life revolves around food. Farmers market, grocery shopping, happy hours, cooking dinner, work lunches, events, etc. You suddenly have all this free time. For me, I just play a lot of golf to take my mind off of it.

If you want an easy version, look up fast mimicking diet by Dr. Longo. Prolon sells premade kits.

Re: Intermittent fasting 2 days vs. 1 day per week

#30

Post by mywittyname »

A4ET8a8uTh0 wrote: post #11
chasebank wrote: post #3

Having water fasted many times, I swear this has something to do with burning all the stored glycogen. I have no backing other than what I’ve experienced myself. I get really hungry for a week after a fast and continue to lose weight or stay the same. Anecdotally, I’ve chalked this up to as long as your glycogen bank isn’t full, you can pretty much eat whatever you want. Water fasting is glorious btw.

Could you elaborate a little about your regimen? Each time I attempted water fasting, the next day I was basically famished ( and needless to say, any progress made was lost ).

How far did you get?

In my experience, the first day is by far the most difficult. I find that it's most effective to start fasting on days where I am going to be occupied with something, since I don't think about food when I'm active.

I'd be miserable if I attempted to fast on a day where I was lounging around watching TV.

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