The FastDay Forum

All online calculators give an educated guess based on assumptions that you are 'typical' (after allowing for the questions they ask). I think your own experience is a better guide, so if you have found that your TDEE is c.1300-1400 calories i.e. this maintains your weight, then I would say that you are probably right and the online calculators are wrong - for you.

I think so too, to be honest!

Just want to say that I have been sticking to a max of 1200 calories on my non-fast days, with only a little extra at the weekends or if I have been very active (which is unusual for me!) and I have been consistently losing weight since the beginning of January (now 9kgs gone). BUT, i was not previously calorie restricting, and this figure is only slightly below my TDEE. In the past I had been advised to eat 1400 calories a day to lose weight, and never got anywhere.

Now with the 3 fast days and the 1200, it is really working for me. I am only 5'0 tall and over 60 years old. So I'm not saying this works for everyone, but if you are small, sedentary and not hugely overweight, a low intake like this may be just what you need.

It certainly hasn't put me into starvation mode!

I'm interested by your experience carorees, I think I need to do a graph tracking weight loss and food intake, side by side.

Probably, Belinda, the difference between you and those on starvation mode is that you only did it to lose weight and it wasn't the way of your living for a long time.
I too plan to alter the way I do 5:2 if I see that my weight loss stops but if I continue to lose weight I'll keep on doing what I'm doing.
As we say in Greece, don't change a tasty recipe.

Not sure if this will work or not, but as I already had the data, I have made a chart showing my weight loss (blue) over the past 3 months, alongside my net calories (red). It is very apparent that the significant dips follow my fast days.
I do Zumba class on fast days, that's why my intake is sometimes negative!
Although I weigh every day, I don't always log it if there is a small increase - I just wait for it to come back down, so there may be some missing peaks!

Graph showing weight loss v net calorie intake

Thanks Belinda that is interesting.

Your basal metabolic rate looks to be about 1100 calories i.e. when you consume net 1100 calories your weight is stable. So it makes sense that you didn't lose weight previously when you restricted to 1400, assuming you were living a pretty sedentary lifestyle at the time that was probably your TDEE. Now you are fasting and zumba'ing and the combination of fast + exercise is clearly working.

Thanks for sharing!

This is interesting for me because I'm allowing myself 1200 calories a day but I work it out over the week, with two fasts. So 1200 x 7 = 8400, less the two fast days @ 500 cals = 7400. Divide this by the five normal eating days and you get 1480. I've been following this regime for a month now and I'm losing two pounds a week. I run x 3 a week and have horses which I ride and poo-pick for daily so I'm an active person anyway. I've lost a total of 35lbs so far, with another 11 to go to my first target (I say first because I may decide to lose a little more when I reach it!). My TDEE is allegedly will be 1742 when I hit my target weight so I'm hoping that the 1480 that I currently allow myself will still keep me going.

When I reach target, then begins the fine-tuning of finding out how many calories I need to eat to maintain.

You have to have common sense and find what works for you as an individual. All the figures quoted are only averages anyway - we're all different.

That's the right way to calculate it. We have seen lots of people over the months do the 1200 per day on feed days and then the 500 on fast days, averaging less than a 1000 so double-counting.

All the figures are approx, including calorie counts on products.