Am I losing muscle by doing Intermittent Fasting?

I've been doing Intermittent Fasting [IF] for the past 5 days and lost 7 pounds so far. YES, I know it is most likely water weight. My concern is that my scale also measures Body Fat % and it has been trending UP while the weight is dropping. Could I be losing muscle?
My usual day is like this:
Wake up - Work out for 45-60 min. [alternating cardio, abs, and resistance each day].
Skip breakfast and lunch. Eat dinner around 5 pm with a 4 hour window, I get in about 1000-1300 calories. I try to eat high fiber/low fat. I usually make about 75% of my protein goal. I usually get 5-6 hrs of sleep.

Any suggestions/observations?

Replies

  • I don't know what your weight is, but you are eating WAY too little. Eat more and more strength training with Heavy weights. 5-6 reps per set.
  • Ainar
    Ainar Posts: 858 Member
    IF won't make you lose any more muscle compared to same amount of calories and protein without IF. Very huge calorie deficit is what may make you lose muscle. So if you are indeed losing a lot of muscle then it's not due to IF but big deficit.

  • joshuak30
    joshuak30 Posts: 110 Member
    If you're losing muscle it certainly isn't because of your meal timing. It's because you're undereating calories and protein.

    Without a lot more information about you, it's hard to give advice other than to eat a balanced diet with a moderate deficit, no more than 20% of your Total Daily Energy Expenditure.
  • TavistockToad
    TavistockToad Posts: 35,719 Member
    what are your stats? why are you eating as little as 1000 cals?
  • ladyhusker39
    ladyhusker39 Posts: 1,406 Member
    You haven't lost muscle in only a week. However, you could be at risk if you eat so little over an extended time depending on your stats. We can't speculate because we don't know any more about you.
  • J72FIT
    J72FIT Posts: 6,002 Member
    Ainar wrote: »
    IF won't make you lose any more muscle compared to same amount of calories and protein without IF. Very huge calorie deficit is what may make you lose muscle. So if you are indeed losing a lot of muscle then it's not due to IF but big deficit.

    Agree with this...
  • Nudgey02
    Nudgey02 Posts: 24 Member
    as above, bump up your calories and lift heavy. I'd go for high protein and fat and reduce carbs.
  • J72FIT
    J72FIT Posts: 6,002 Member
    Nudgey02 wrote: »
    as above, bump up your calories and lift heavy. I'd go for high protein and fat and reduce carbs.

    Why would you reduce carbs?
  • walijan
    walijan Posts: 9 Member
    edited December 2017
    OK, a little bit more about me:
    -Male 53 y/o
    -Got a spare tire and man boobs.
    -260 lbs [now] My fitness goal is to get to 180 or solid body [without bulking], whichever comes first.
    -MFP says I should aim for 1500 cals which I do hit and exceed doing 3 meals a day, but I was getting no results and was usually gaining weight. Was doing that for a year before deciding to do IF.
    -I eat about 1000-1300 during my window because I really feel full and am not trying to go to sleep on all that food.

    I hear you, saying I should increase cals and protein. Would a protein shake with dinner help?
    Also hear you with the heavier lifting. Guess I'll either have to get more weight plates as I prefer working out at home than a gym. I was hoping high reps would get me there but I guess not :'(
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited December 2017
    IF shouldn't be fewer calories than other ways of keeping a deficit, so assuming your protein is as high as it otherwise would be, no, it won't cause muscle loss.

    If your way of doing IF is to use it to have an extreme deficit, it will affect you like any other extreme deficit, which can lead to muscle loss, yes.

    5 days is nothing, however, and you haven't lost 7 lbs of fat OR muscle, you've lost some water and probably a little fat. It does seem like your calories are far too low, though, so I'd fix that.
  • canadianlbs
    canadianlbs Posts: 5,199 Member
    edited December 2017
    proportionate uptrending isn't the same as an increase in absolute body fat. so maybe it's that? water counts as 'lean' weight. so if your lean weight dropped 7 pounds while your body fat remained stable, the 'proportion' numbers would change.

    i feel too inarticulate to explain the point any better than that, but maybe i've already made enough sense.

    also, 1500 calories wha? others have already caught it, but just to rub it in: i'm almost your age and less than half your weight. and 1500 is probably maintenance or even a bit of a deficit for me.
  • AnnPT77
    AnnPT77 Posts: 34,173 Member
    J72FIT wrote: »
    Nudgey02 wrote: »
    as above, bump up your calories and lift heavy. I'd go for high protein and fat and reduce carbs.

    Why would you reduce carbs?

    Heck, in this case, probably even I'd say that, and I'm not any kind of low carber! ;)

    OP said he was pursuing high fiber, low fat, and 'usually' hitting 75% of protein goal. Unless his protein goal is way above default - which happens, I admit - it sounds like he's eating a boatload of carbs in his meager 1000-1300 calories, and not enough of anything else. No balance.
  • middlehaitch
    middlehaitch Posts: 8,486 Member
    @walijan, if you are IF-ing and can only get 1000-1300 in in that window you may want to look at a broader eating window.

    That being said, there is no magic to IF, if it is your preferred way of eating, carry on. If you prefer eating at a different frequency, change to that.

    You are in this for the long haul and establishing a way of eating that will last you the rest of your life is important, not establishing the fastest way lol lose weight.

    When it comes to your food, if you were not losing on the men's minimum of 1500 cals, it was problems with your logging, not the calorie amount.

    Put your stats in to lose 1.5-2 lbs a week.

    Buy a food scale.

    Aim for .5-1g protein per lbs lbm, or use the mid range BMI.

    Use the food scale to weigh everything you eat packages, single servings, meat, veg, sauces, dressings, oils, and butters everything. Liquids are cups and spoons.

    Eat back your exercise calories, you may not need them now, but you will, so it is good to account for them from the beginning.

    There are a number of good well planned routines that you can follow at home (link below), choose one that aligns with your fitness level now and work it until progress stops and you need to upgrade your programme.

    Don't go hell for leather into exercise, this will probably lead to burn out, or injury, start slow and steady and build from that.

    (To put your 1000-1300 cal in context, at 54, F, 5'1, 130lbs I lost weight eating all the food I loved, timed in a way that I knew was sustainable, for the first 10lbs at 1lbs a week on 1200 cals plus 200 for exercise. I started weight training with Nerdfitness and Dumbbells, then progressed to a barbell routine)

    Cheers, h.

    Ps I lost the weight and have been maintaining for 7+ years. Find what works and is sustainable. Putting a year into learning how to work out and eat in a sustainable way, for me, while losing 30lbs and getting fit and healthy was not a waste of a year.
  • gpokerlund
    gpokerlund Posts: 16 Member
    Do your research on intermittent fasting. Depending on how much protein you consume during your eating hours you may or may not be in a catabolic state when you are fasting in addition to that, women arent as anabolic as men so women typically would be a bit catabolic. But, what is your goal? Losing fat? Or gaining muscle? Its impossible to do both simultaneously with sacraficing one of the two, to some degree.
  • SezxyStef
    SezxyStef Posts: 15,267 Member
    you will lose muscle regardless...there is nothing we can do to stop it all together while losing weight.

    You can lessen the amount by getting in adequate food, protein and doing some form of resistance training...but you will lose some.