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Why does MFP say I will lose X lbs in 5 weeks?

ainokea8
ainokea8 Posts: 95
edited February 12 in Health and Weight Loss
After you enter in your food diary, it says "if everyday is like today you will lose X lbs in 5 weeks"

So for example, my starting weight is at 115 lbs. And it says I will be down to 114 lbs in 5 weeks.

Isn't the calorie goal set so you would lose 1 (or 2) lbs within 1 week? So by 5 weeks I should already be at 110 lbs not 114 lbs, assuming everyday is like today.

I know it's just a small detail, but I'm curious what this means.

Replies

  • parkscs
    parkscs Posts: 1,639 Member
    It's just an algorithm. For instance, if you were 500 calories under your TDEE today, MFP will tell you you'll lose 500 * 7 * 5 / 3500 pounds in 5 weeks.
  • Akraz
    Akraz Posts: 41 Member
    It goes based off your current profile. In accordance to your heigh/weight, it does BMR calculations behind the scenes and adds it to any calorie burns youve done that day (cardio) - the BMR + Caloric burns = TDEE.

    If you were unaware, like parkscs said, there is 3500 calories in 1lb of body fat.

    Assuming your BMR + Caloric burns was 2100, if you ate 1592 calories that day, you were a deficit of 508 calories.

    Multiply 508 * 7 days * 5 weeks = 17800 calories "burnt".

    17800/3500 = 5.08 lbs

    But you would have to be at a 500 caloric deficit every day for 35 days.
  • parkscs
    parkscs Posts: 1,639 Member
    17500/3500 = 5, but otherwise agree entirely. :smile:

    Basically, it pretends that your caloric deficit for the next 5 weeks will be exactly the same as it was today, and it tells you approximately what you'd weigh if that was the case.
  • Akraz
    Akraz Posts: 41 Member
    17500/3500 = 5, but otherwise agree entirely. :smile:

    Basically, it pretends that your caloric deficit for the next 5 weeks will be exactly the same as it was today, and it tells you approximately what you'd weigh if that was the case.

    Had a preschooler moment. I subtracted rather than divided. Fixed now. LOL
  • Amiwil
    Amiwil Posts: 57 Member
    After you enter in your food diary, it says "if everyday is like today you will lose X lbs in 5 weeks"

    So for example, my starting weight is at 115 lbs. And it says I will be down to 114 lbs in 5 weeks.

    Isn't the calorie goal set so you would lose 1 (or 2) lbs within 1 week? So by 5 weeks I should already be at 110 lbs not 114 lbs, assuming everyday is like today.

    I know it's just a small detail, but I'm curious what this means.

    It's just an assumption from what you're doing. Good luck!
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    So for example, my starting weight is at 115 lbs. And it says I will be down to 114 lbs in 5 weeks.

    For the example you gave, it means that you are eating more than your target and are barely at a deficit at all, at least for that day.
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