question about TDEE and fast day calories

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question about TDEE and fast day calories

This topic contains 8 replies, has 7 voices, and was last updated by  simcoeluv 10 years, 4 months ago.

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  • If my TDEE is closer to 1600 calories than to 2000 calories, and my fast day calories should be about 1/4 of my daily requirement, shouldn’t my fast day calories be 400 rather than 500? 400 calories per day would sure be a lot less comfortable, but I can’t help but wonder… maybe try 500 calories and only cut back to 400 if I don’t lose weight?

    Hello franfit 🙂
    I personally do not think it would make a big difference (what comes to weight loss) if you would have 400 kcal on the fast days.

    Currently your weekly calorie deficit is
    2 x (1600 – 500) = 2200 kcal, approx. 300 g weight loss per week

    If you would have 400 kcal on your fast days, the calorie deficit would be
    2 x (1600 – 400) = 2400 kcal, approx. 350 g weight loss per week.

    So instead making the fast days more difficult, I would have more exercise or less calories on non-fast days.

    The fast day calorie limit does have impact on e.g. IGF-levels, but it is hard to believe that eating 400 kcal instead of 500 kcal would have a big impact, especially when considering that the calorie counting system as such is not accurate (cooked vs uncooked food).

    Thank you viisikaksi. I was wondering if it was important to get down to 1/4 of your caloric requirement in order to make the magic of fasting happen.

    Thank you viisikaksi and franfit. I woke up this morning with exactly this question on my mind. My TDEE is only 1430 and I was thinking that I would need to reduce my fasting day limit to 375, which isn’t a happy thought.

    What on earth is TDEE ???

    hi banana21

    here is what jeanius wrote

    Jeanius

    9:39 am on 5 Jun 13

    calculating one’s TDEE (Total Daily Energy Expenditure). To my mind, the TDEE figure (based on one’s individual statistics and activity levels) represents the appropriate healthy daily intake for the five non-fasting days of a 5:2 regime and, then, one factors-in the low-calorie intake of the two fasting days in order to achieve weight-loss. It seems many people think that a more drastic weekly calorie-reduction will automatically lead to a greater weight-loss. That seems to be true in the short-term but in the long-term it: a) is usually too difficult to sustain; b) leads to a greater loss of lean muscle (rather than the more-desirable loss of fat); and c) seems to slow down the metabolism more quickly, thus making weight-loss even more difficult. All dieting systems seem naturally to lead to plateaux and a gradually slowing of metabolism/weight-loss, so, adjustments have to be made as one progresses, but, if one is patient and pro-active then, I think, those stages can be overcome and further benefits and weight-losses achieved. (Oh, It just occurs to me that, as soon as one achieves a good weight-loss, then one’s TDEE needs to be re-calculated, as one’s daily intake needs to reduce too. I wonder how many people have also failed to realise this?)

    My TDEE is 2270…. Should I have more than 500 on fast days? 🙂

    Sara:

    I guess it depends on how much you want to lose, how fast. If you are in no hurry, eat more. My TDEE is higher than yours, but I usually eat 0 calories on my diet days.

    Good Luck!

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