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Ruining Metabolism, Cheat days, etc.

Hi! I'm looking for information on current nutritional advice and research on how much of a calorie deficit and reduction from normal leads to a "wrecked" metabolism. I started MFP 2 weeks ago, 160 lb female at 5'7" and 38 years old. I have stayed just under the 1280 calories plus about 300 that I eat back from exercising each day, during these two weeks. I have lost 1.5 lbs a week, which is fine with me. However, I am eating much, much less than I did before I started and want to know what the current understanding is "wrecking" your metabolism. Also, a friend recommended a cheat day once a week so that my metabolism stays high, and I know nothing about that idea. Thank you!


  • MichelleSilverleaf
    MichelleSilverleaf Posts: 2,027 Member
    I think it would honestly take a lot more and a lot longer to truly wreck your metabolism, but depending on what weight you're trying to get to that 1.5lb/week may still be a little on the aggressive side. Certainly not an amount you're going to be able to keep up all the way to goal anyway. I wouldn't bother with a cheat day myself, I don't find the point of them and when you don't have a lot to lose a cheat day or cheat meal could wipe out your progress, or at least hinder it.
  • amgreenwell
    amgreenwell Posts: 1,267 Member
    I guess I've never heard that term before "wrecked metabolism". I just know you eat less calories than you burn you will lose weight. If you work out on top of that then you are keeping your metabolism going as well.
    I don't do cheat days either, I fit whatever I'm going to eat that day into my calorie count or I work out more so that I can eat whatever it might be that I want. I don't want to deprive myself of anything.
    I also log everything I eat in the morning so I know where I stand from the beginning of the day.
  • jjpptt2
    jjpptt2 Posts: 5,650 Member
    I haven't read anything that stated specific numbers, but based on what I think I might know, I think damaged metabolisms fall more in line with the following -
    1. malnutrition
    2. significant calorie deficit - well below BMR (not simply below "normal" eating, whatever that is)
    3. both 1 and 2 occurring consistently for an extended period of time - much longer than what most people think when they talk about these types of topics.
  • littlebear0121
    littlebear0121 Posts: 1,073 Member
    amgreenwell, I love your ideas. Thank you. Thank you, jjpptt2 for your explanation.
  • AnnPT77
    AnnPT77 Posts: 33,041 Member
    Common rule of thumb around here is to lose no more than 1% of your body weight weekly, and less than that is better when you get close to goal (say a pound a week at 25 or so to goal, half a pound at around 10 or so).

    "Wrecked" metabolism isn't really a thing, but we risk negative health consequences by losing too fast - one is a tendency for fatigue to subtly slow down our daily activity level and thus slow our weight loss; another is unnecessary muscle loss that can do a similar thing.

    This thread is informative: