MFP vs. IIFYM

So, I put my info in IIFYM, with the correct activity level, and it told me I should eat 1700-1900 calories/day, depending on the formula (the one where you enter your body fat % told me 1900).

I had my goal at 1500 but I tried to eat more, I was losing a little less than a pound some weeks (my goal is 1 lb.) so I figured why not try it, plus it is hard eating less and lifting weights.

The past week I averaged 1600 calories/day, my weigh day is Thursday but my scale already says I am down more than 1 lb., but I am going to wait till Thursday than average out the week (I weigh myself every morning).

I think I am doing this right, but should I try to get to the 1700/day? When I changed my goal to 1600, MFP said I will lose 0.3 lbs per week, but I already know that is not what happened, yet I have to try this a little longer to feel comfortable with it.

Coupled with getting smaller from lifting weights, the whole thing seems sort of strange and somewhat counter-intuitive, but you can't argue with success...and it is very important to me to keep as much of my muscle as I possibly can.

Replies

  • terbusha
    terbusha Posts: 1,483 Member
    What I do and what I recommend to people is to eat at a calorie level that allows you to drop 1-2 lbs/week. This assumes an average calorie burn from you getting in all of your workouts. This will be different for everyone, so you'll have to do some trial and error to figure it out. I'd start ~1600 cal/day. Hit this goal, along with your macros and getting in your workouts, for a week. If you lose 1-2 lbs, you're good to go. If you lose too much, increase your intake and repeat. If you don't lose enough, reduce your intake a bit and repeat. After a few weeks, you'll figure out what works for you in your situation.

    Allan
  • SezxyStef
    SezxyStef Posts: 15,267 Member
    The different between the two is that MFP assumes you are at the activity level you have set...probably sedentary and you aren't doing exercise.

    IIFYM assumes you are exercising hence the increase in calories.

    When I switched to TDEE (iifym) -15% I was losing steadily as well...and at first it was quite a bit...now mind you I can go weeks without a loss then a whoosh of 2lbs in one week gone...it's great...
  • perseverance14
    perseverance14 Posts: 1,364 Member
    Thanks to both of you.
  • catfive1
    catfive1 Posts: 529 Member
    If you are using IIFYM you don't eat back exercise calories. Also, try and hit the macros.
  • jaxxie
    jaxxie Posts: 576 Member
    Absolutely aim for your macros! It's the best way to success....without deprivation and it is sustainable. I love it! Good luck!

    Edited, keep in mind MFP is usually wrong in terms of calories, so weigh in grams and be as accurate as possible.
  • Aaron_K123
    Aaron_K123 Posts: 7,122 Member
    Honestly from the short time I have been around on MFP the number one problem I see people having on these forums is that so many are consistently undereating. Have to shake the notion that 1600 calories is somehow a lot...it really isn't. If you have fears about it just bump yourself up slowly like you have been doing and keep tracking your progress.

    I'm just happy to see someone not eating 1200 calories a day to be honest.
  • ILiftHeavyAcrylics
    ILiftHeavyAcrylics Posts: 27,732 Member
    MFP is assuming you're going to eat back your exercise calories. IIFYM.com is assuming you're going to exercise but will not eat back the calories, because they're already figured in.
  • psych101
    psych101 Posts: 1,842 Member
    ...now mind you I can go weeks without a loss then a whoosh of 2lbs in one week gone...it's great...


    haha me too!! I'm same same same WHOOSH lol
  • Mischievous_Rascal
    Mischievous_Rascal Posts: 1,791 Member
    I lost weight every time I increased my calories, too. Now MFP tells me daily that I'll gain weight eating as I do, but I maintain just fine on way more than this site would give me. I kept adding 100 calories a day every four weeks when I made the switch to TDEE, just to be sure everything was decreasing steadily. Just make sure you're treating your protein and fat goals as minimums.

    And learn to welcome the whoosh! lol
  • I3righti3lue24
    I3righti3lue24 Posts: 40 Member
    Keep in mind too being a women our water weight can really fluctuate through out the month because of our menstrual cycles too. So sometimes you may see a larger gain or a larger loss than expected.
  • athensguy
    athensguy Posts: 550
    I just did the iifym calculator using Athlete's formula with Every Day *intense.

    It's way below what I actually eat. The maintenance amount is about what I eat without exercise calories added back in.