The FastDay Forum

Hi,

I know I posted last night about my week-end bingeing, hence now I am analysing my 5:2 strategy and thinking of possible changes.

Can anyone shed any light on the following: How about eating lower than TDEE Maintenance Calories (perhaps as per the Extreme Loss on the calorie calculator) on Feast days then you'd lose even more weight? There has been talk about not eating enough and need to eat up to the recommended TDEE to trigger your metabolism.

Bit confused by it all.

xx

Eh?

No, don't starve, you'll fall over. Basically, you're looking for a calorie deficit over the week. Think in terms of months and weeks, not days.

So, assuming you're not very small or large or exercise tonnes, eat on average about 1500 calories a day, 2000 ish on most days, 500 on fast days. Obviously if you then don't lose weight over a month or so, then fiddle about but atm, keep it simple.

Or 1800 ish on feed days (waiting to be told 2000 is too much) but don't be averaging less than 1200 cals per day averaged over the week...

Hi Elli

I think you should get plenty of answers to this question and you might not be much the wiser at the end of them all. The jury is out on this one.

There is a view that eating less than your TDEE on feed days will lower your metabolism and therefore make it harder to lose weight. A possible way around this it to eat your TDEE on some feed days and eat less on others, thus allowing the 'normal' days to keep your metabolism up to the mark.

The only honest answer is that we don't know. Personally I think an overall reduction in calories consumed will lead to weight loss, but it mixing up the way in which you consume the calories might (or might not!) be even more effective. It's kind of 'maxi 5:2' where you extend the idea of fast/feed into the feed days: fastest/fast/feast.

So if you were working off a TDEE of 1800 calories this might translate as 500 x 2, 1400 x 3, 2400 x 2.

If you feel this all sounds a bit obsessive, I wouldn't disagree...

Yes, I see where you're coming from.

Also hearing from some on this forum where if you are NOT sticking to the same number of calories every day helps, one day few more one day few less, like you say.

It's all worth a try. Bit of trial and error for those of us not losing much.

Thanks

I go with eat if you're hungry or weak or fainting, don't eat if you're bored or unhappy.

Eat more on feed days, less on fast days and eventually, given the calorie restriction, you'll lose weight.

[carorees]

My theory, for what it's worth, based on my experience and on various posts I've seen here, is that following a bit of a binge I have lost more weight than sticking religiously to TDEE or below on feast days. Obviously you can't binge everyday and lose weight but I think that eating in the way Dominic has suggested gives some advantage. Now whether that is purely down to changes in metabolic rate or to the psychology of being allowed to have a real feast occasionally or a change in the balance of types of food (binges not generally being associated with healthy eating) or a combination of all these (and more), I don't know. I do think though that having a variable eating pattern gives the diet more flexibility and that must be a good thing...

And Caroline's example is a much more real-world instance of how this kind of approach can work. Rather than trying to micro-manage your calorie intake over the week, just bear in mind that if you binge one day you ought to mini-fast another (and still keep to your 2 days proper fasting as well). This "unhealthy" lifestyle might actually be more effective for weight loss than eating exactly your TDEE on 5 days. Even if it isn't, it's unlikely to be much worse, so it gives you a 'way back' after a binge...

And not having any guilt (reward) and limiting self-sabotage means that adherence is better, as you can't really fall off the wagon, other than by not fasting properly.

I also think that varying calories works better. I think you unconsciously limit calories later if you eat more or higher calorie food, if in tune and relaxed about food intake.

There is a view that eating less than your TDEE on feed days will lower your metabolism and therefore make it harder to lose weight.

Is there any evidence for this?

No scientific evidence that I am aware of Pip, but some anecdotal evidence from this forum. It's a hypothesis.

No scientific evidence that I am aware of Pip, but some anecdotal evidence from this forum. It's a hypothesis.

I'm just wondering what is the scientific basis for the whole 'reducing cals reduces your metabolism' rumour. Is it simply a misunderstanding of the fact that the less you weigh, the slower your metabolism?

[carorees]

Have spent an hour or so searching. Several papers report decreases in resting energy expenditure with dieting, especially with very low calorie diets. The decrease in energy expenditure recovers on re feeding. Mostly they were not very recent studies, however, I just found this recent study:
http://www.ncbi.nlm.nih.gov/pubmed/23535105
Following the related citations link revealed this:
http://www.ncbi.nlm.nih.gov/pubmed/19660148
And this: http://www.ncbi.nlm.nih.gov/pubmed/19710198

Have spent an hour or so searching. Several papers report decreases in resting energy expenditure with dieting, especially with very low calorie diets. The decrease in energy expenditure recovers on re feeding. Mostly they were not very recent studies, however, I just found this recent study:
http://www.ncbi.nlm.nih.gov/pubmed/23535105
Following the related citations link revealed this:
http://www.ncbi.nlm.nih.gov/pubmed/19660148
And this: http://www.ncbi.nlm.nih.gov/pubmed/19710198

It says weight loss slows the metabolism, but is it the actual process of weight loss which does this, or is it simply the fact that the less you weigh, the slower your metabolism? So my metabolism would be faster at 9st than 8st. This doesn't prove that dieting itself slows metabolism.

[carorees]

No, it says metabolism slows by more than predicted from the body composition, so your metabolism is disproportionately slower after dieting down to 8st than if you had been 8st all along.

RESULTS:
The ratio of RMRm to RMRp decreased from 1.004 ± 0.077 before the diet to 0.963 ± 0.073 after the diet (P < 0.001)

RMRm = measured
RMRp = predicted

No, it says metabolism slows by more than predicted from the body composition, so your metabolism is disproportionately slower after dieting down to 8st than if you had been 8st all along.

RESULTS:
The ratio of RMRm to RMRp decreased from 1.004 ± 0.077 before the diet to 0.963 ± 0.073 after the diet (P < 0.001)

RMRm = measured
RMRp = predicted

Oh dear


Is this the body rebelling against the diet?

Do you know if there are any studies which show ways you can increase metabolism? (the holy grail I know, perhaps exercise?)