The FastDay Forum

5:2 Diet 'Rules' & Variations

11 posts Page 1 of 1
Yet another question from me but I'm yet again confused.
I read (forgive me but I canny remember where) that on fasting days it is sensible to eat our TDEE divided by 4.
But I also read that the common number for fasting days is 500 for women and 600 for men.
Which one is true? Or are both true?
The thing is that the TDEE/4 method is confusing me because I found 3 different TDEEs for me online, I have a thyroid that isn't working so any TDEE is probably not accurate plus, as I lose weight (which I hope will happen), my TDEE will be reducing.
On my first two fasting days, I consumed 441 calories because that was the 1/4th of the first TDEE that I found online.
Shall I stick to that and not think of it too much???
Well Dr M did tweet the other day that he thought you shouldn't go below 500 but I think it depends how you feel. Possibly in the case of thyroid problems going too low could be a problem, but then you need a big difference between feed day and fast day cals. So I'm going to say that you can choose either 1/4 or 500 depending how you feel! Not too helpful I know, but flexibility is the keystone of this diet!

I think you have to experiment with the right feed day cals. Although your thyroid problems affect your TDEE, the whole feast/famine thing may change things too. I would suggest risking a higher feed day figure at first and also trying to mix things up as much as possible so you don't have the same kind of calorie intake every feed day. (that's what weekends are for of course ;-))
I'd stick with 500 too, even before hearing Dr. M said that.
carorees wrote: Well Dr M did tweet the other day that he thought you shouldn't go below 500 but I think it depends how you feel. Possibly in the case of thyroid problems going too low could be a problem, but then you need a big difference between feed day and fast day cals. So I'm going to say that you can choose either 1/4 or 500 depending how you feel! Not too helpful I know, but flexibility is the keystone of this diet!

I think you have to experiment with the right feed day cals. Although your thyroid problems affect your TDEE, the whole feast/famine thing may change things too. I would suggest risking a higher feed day figure at first and also trying to mix things up as much as possible so you don't have the same kind of calorie intake every feed day. (that's what weekends are for of course ;-))


I never saw that tweet, and I follow him on twitter. Maybe I missed it, but from what I understand is that you should take in 1/4 of TDEE or less. You can have zero calories if you like and there is no harm in that. The reason he/they chose 500 for women is because it is a) an easy guideline to remember and should apply to MOST women as being 1/4 TDEE and b) a complete water fast is very hard to do and this diet is all about sustainability.

I have yet to eat 500 calories on a fast day. I generally do around 400 or less. I just eat enough to keep the horrible hunger pains away.
Ah, the weekends! The calories of my feed days do vary since when I'm at home I eat more sensibly than when I'm not.
Saturday was 1153 calories, Sunday was 1406 calories and today was 1428 but that's too much for me (or so I think).
I think I'll go for 450 and see how it goes and never go under 1100 on feed days. Mind you, I don't eat less on purpose. It's the way I cook that makes my food poor in calories, because I hate too much oil!
Rufus wrote:
carorees wrote: Well Dr M did tweet the other day that he thought you shouldn't go below 500 but I think it depends how you feel. Possibly in the case of thyroid problems going too low could be a problem, but then you need a big difference between feed day and fast day cals. So I'm going to say that you can choose either 1/4 or 500 depending how you feel! Not too helpful I know, but flexibility is the keystone of this diet!

I think you have to experiment with the right feed day cals. Although your thyroid problems affect your TDEE, the whole feast/famine thing may change things too. I would suggest risking a higher feed day figure at first and also trying to mix things up as much as possible so you don't have the same kind of calorie intake every feed day. (that's what weekends are for of course ;-))


I never saw that tweet, and I follow him on twitter. Maybe I missed it, but from what I understand is that you should take in 1/4 of TDEE or less. You can have zero calories if you like and there is no harm in that. The reason he/they chose 500 for women is because it is a) an easy guideline to remember and should apply to MOST women as being 1/4 TDEE and b) a complete water fast is very hard to do and this diet is all about sustainability.

I have yet to eat 500 calories on a fast day. I generally do around 400 or less. I just eat enough to keep the horrible hunger pains away.


Apologies it was not a tweet, it was on the fast diet website. Someone commented that their TDEE was below 2000 so should they reduce fast day cals and Michael got in touch to say no:

Fabulous50
5:31 pm
25 Feb 2013
Permalink

I’ve just calculated my TDEE (http://www.fitnessfrog.com/calculators/ ... lator.html) and it’s a rather alarming 1519 calories a day – quite a bit less than then rough guide of 2000 for women! This means at 25% calorie intake for a fast day, I should be eating 380 calories! Well I’d better give it a try…!

Update – Michael has been in touch to say stick to 500 cals – phew! Should be MUCH easier! Thanks Michael.
This is Dr M's diet and his are the official rules, and he makes them as simple as possible, hence the 500/600 cal limit.

I am sure the underlying logic is 25% of TDEE, but that means you have to work out your TDEE and it all gets messy and subjective. That's why the forum policy is that anyone eating more or less than 10 calories over/under their 500/600 calories on a fast day is banned, has all their posts removed and has to apologise publicly before they are allowed back.

:wink:
There's nothing especially magical about 25% - why isn't it 26% say, or 22%?

It's a rough guide. "Around" 500 cals is fine....


(.....She says, but then we all know we're the guinea pigs here, not enough research as yet)
dominic wrote: This is Dr M's diet and his are the official rules, and he makes them as simple as possible, hence the 500/600 cal limit.

I am sure the underlying logic is 25% of TDEE, but that means you have to work out your TDEE and it all gets messy and subjective. That's why the forum policy is that anyone eating more or less than 10 calories over/under their 500/600 calories on a fast day is banned, has all their posts removed and has to apologise publicly before they are allowed back.

:wink:

:lol: :lol: only had 475 yesterday...I'm off to ban myself!
I only had 260 yesterday, guess I'm off too! ;) it was the most huge salad ever and I could barely finish it! I thought I'd have a hot choc in the evening but didn't fancy it in the end.
I plan to have 460 today. I apologise in advance if that will work. It was nice to meet you all, LOLOLOLOL!!!!
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