Combining intermediate fasting with calorie restrictions

I am 47 M and gained a bunch of weight during COVID 6’ft 267, and decided I needed a change. I have been doing the 16:8 combined with a calorie restriction of 1200, and cardio 5 days a week. The IF naturally forced me to consume less calories. I know 1200 is too low and will gradually increase of weeks to come. I do high protein with lots of veggies and keep the carbs to under 50’grams. I target 40% protein, 40% fats and 20% carbs. I am averaging 3.5 lbs loss per week and down to 238. I have a ways to go to get to my 200 lb goal. Has anyone else had success with combining the two?

Replies

  • Justin_7272
    Justin_7272 Posts: 341 Member
    A lot of people on here do IF and have been successful. I think it's a good method if you have difficulty controlling eating throughout the day and can stick to your window. Eating outside your IF window is inherently (though probably not intentionally) designed to cause feelings of guilt/shame, so it may not be good for people that have problems handling those feelings.

    If you're focus turns to losing weight AND building muscle (or just building muscle in general) it's far from ideal. For purposes of muscle growth, your body can process roughly 10g/protein/hour. You could do IF and allow for protein shakes outside your window to counter this.

    Overall there's nothing weight-loss wise that IF will change from a scientific standpoint, as it doesn't change the fact you need to be in a caloric deficit. Some people will talk about metabolism change, but that is extremely minor if it does occur; we're talking <100 calories, so don't buy that hype. I do believe there are studies that show it may have positive affects on other health aspects (things like blood pressure, glucose regulation, etc.) so if that's something you're interested in it is worth exploring.
  • yukfoo
    yukfoo Posts: 871 Member
    edited April 2022
    Wow! The rebound on this is going to be horrendous. 100% rebound plus ~10% or more within a year is my guess. Please stay in very close contact with your health care provider. You're heart will thank you.
  • sijomial
    sijomial Posts: 19,809 Member
    Yes I did IF (not 16:8 though) and combined it with a calorie deficit.
    But I kept at a modest deficit of 1lb/week loss.

    Your current rate of loss sounds like a terrible idea TBH.

    Although prioritising protein during a huge deficit makes sense it would be better to avoid the huge deficit in the first place.
    Protein is muscle sparing but so are carbs and keeping to a healthy rate of loss.
  • sstanton75
    sstanton75 Posts: 3 Member
    yukfoo wrote: »
    Wow! The rebound on this is going to be horrendous. 100% rebound plus ~10% or more within a year is my guess. Please stay in very close contact with your health care provider. You're heart will thank you.

    Yukfoo - great words of encouragement! I look forward to proving you wrong. Also great insight on modifying!
  • PAV8888
    PAV8888 Posts: 14,275 Member
    edited April 2022
    Your question.
    Your implementation.
    Oh my.

    You're losing weight because you've implemented a caloric restriction of approximately 60% of the calories required to maintain your weight while on average ingesting 40% of your total daily energy requirement.

    If you had implemented an effective caloric restriction equal to 1% while consuming 99% of your tdee, you would have still lost weight; albeit less than you've lost so far.

    You COULD have implemented the caloric restriction by spending all your day rubbing the top of your head clockwise with your left hand, while rubbing your belly in a counterclockwise direction using your right hand.

    Instead you chose to use willpower and to limit your eating window to 8 hours a day.

    Different things work for different people with various degrees of success.

    Different things work at different times differently for a particular person too.

    The only constant is the need to adjust.

    You asked if caloric restriction implemented via the method of intermediate fasting can work to help someone manage their weight.

    Out of the subset of people who have tried appropriate caloric restriction using any method including IF, a lot have failed, and a good number have succeeded.

    I will assume you would rather succeed. Hence your question.

    But the issue is not HOW you've chosen to implement your caloric restriction, the issue is that in your quest for success you've chosen to one up Ansel Keyes and outdo the Minnesota semi starvation experiment!

    Why bother to implement only a 50% deficit you've implicitly said, when i can do 60%! Right?

    The good news is that you have "only" gone 8.5 or so weeks, not 24. And that your starting energy reserves were higher than those of the participants.

    The bad news is that instead of realizing that it's time to adjust and to bring your deficit to a safer zone for weight loss. A zone suitable for people who actually value their health. Oh let me think. Ah, an idea! Somewhere not exceeding the 20% of TDEE. Maybe 25% of TDEE while still carrying energy reserves that would classify you as obese.

    Instead of doing that you're starting to think that you should plow on ahead and prove the world wrong!

    The world doesn't care. And will probably never know whether you were right or wrong.

    Your health WILL care!

    Remember being a teenage boy? Hormonally controlled?

    Don't be a teenage boy... just pass them on your way up the hill while carrying bags of groceries by implementing a better plan that will work much better than all the willpower in the world!

    Its time to adjust and to start looking for sustainability of effort and long term management of your weight.

    I can guarantee you that rubbing your belly with a 20% deficit has a higher chance for long term success than ANY plan that involves continuing with a 60% deficit

    Your workouts will be better.

    You will have time to adjust and embed changes.

    You may get to keep your gallbladder.... good stuff all around!


  • sstanton75
    sstanton75 Posts: 3 Member
    @PAV8888 and everyone, agree the caloric intake is too little. How do I calculate the optimal amount? I am ready to dial it up. Thank you in advance.
  • autumnblade75
    autumnblade75 Posts: 1,661 Member
    Myfitnesspal has a guided system to set up your calorie goal. That's a pretty good place to start. Under "Settings" you should look for the option to "Update diet/fitness profile" and input your stats. Don't forget to eat back at least some of your exercise calories in addition to the base goal.

    If you're still losing faster than 2 lbs per week (on average, because fluctuations happen) for an extended period, adjust your goal until you find the sweet spot. By that, I am suggesting making a single change and tracking what happens over the next month or so before changing your goal again.
  • PAV8888
    PAV8888 Posts: 14,275 Member
    edited April 2022
    I would, frankly, dial down to 1.5 lbs per week. Use a weight trend app to monitor trend as fluctuations will start increasing.

    And keep dialing down and extending time aiming for continuity of effort and compliance. More success in the 0.5% body weight per week near the end than say the maximum 1%.

    Also not sure where normal weight is for 6ft. Faster loss while high overweight/obese tends to go better than below mid overweight.

    The landing and the next year or two. That's the lotary all this is buying you a ticket for and what I would be trying to set up.

    Aiming for 1200 Cal doesn't really tell me what you're actually eaten. How accurately you log. No info on how active etc.

    All I have is 29lbs in 58 days which means an evidence based (had this been a trend weight as opposed to scale weight) of about 1750 Cal a day.

    So about 3000 Cal a day which if your activity is increasing, frankly, seems normal/lowish for a 6ft male carrying weight

    (I'm just under 5ft 8, got to MFP just a year or so older than you at a similar weight and ate 2550 carefully weighted and measured Cal btw Nov 2014 and Nov 2015 to lose at a rate of just under 1.5lbs at an effective deficit of 695 cal a day. Have continued eating in the 2900-2950 range by yearly average. Lost 10lbs the second year of mfp. Have been stable-ish in the 155 +/- 3lb range for 5+ years with a dip as low as 150 and a scare as high as 160. Active in terms of daily walking. No formal exercise)

    To me 3000 cal a day tdee says 1.5lbs a week and 2250 eating. Caveats are many. How you count. Your activity. How much your activity level and tdee have changed between day 1 and now. How you react to scale weight and non fat weight changes which are going to increase (that's why trend app is good)

    As a guy, if you're not sore from exercise and don't have sodium changes influencing your weight you can usually tell how you're doing using three week averages. Two in a pinch

    Visiting the "larger losers" forum group (taglined "no quitters here") when aiming for 75lb or larger losses is a non terrible thing!
  • AnnPT77
    AnnPT77 Posts: 34,434 Member
    PAV is giving you great advice here, OP.

    You can look at it as proving how tough and determined you are, by eating at ridiculously low calories to prove us all wrong.

    Or, you can look at it as trying to find new, reasonably satisfying life habits you can stick with to lose weight, and continue long term to stay at a healthy weight long term, ideally permanently, almost on autopilot. Successful weight management is not an extreme project with an end date, after which things go back to normal. It's a lifelong endeavor.

    If I were 47 M, gained a bunch when life got complicated during Covid, I'd be thinking about how to avoid being back here at 57 (if not earlier) because life got complicated in some other way. Every round of extreme loss and regain makes the next round more challenging, through things like unnecessary loss of lean tissue, and training the body to conserve calories (less fidgeting, slightly lower body temp, slower hair growth (or thinning), etc.). Bodies get good at what we train them to expect. An extreme diet is indistinguishable from famine, physiologically.

    As an aside, 1200 calories was way too low for me, as a 5'5" 59-year-old woman, when I weighed nearly 100 pounds less than you do now, even when the weight-loss calculators said that's what I would need to eat for moderate loss. (I lost too fast, turned out to be an unusually good calorie burner for a li'l ol' lady.) Even though I felt fine, energetic, not hungry . . . I suddenly hit a wall, got weak and fatigued, then it took weeks to recover - no one needs that.

    You're 7" taller, nearly 100 pounds heavier, 12 years younger, and 100% more male than I am. Odds that you should be eating as few as 1200 calories daily? Very, very low odds.

    On top of that 40% of 1200 calories is 120g protein. I eat that much most days, at less than half your current size. You'd be better off, when losing weight and doing exercise, to be getting more like 145-182g protein minimum, per this research based estimator:

    https://examine.com/nutrition/protein-intake-calculator/

    Explanation here:
    https://examine.com/guides/protein-intake/

    Then there's this, on the extreme downside, that happened to a woman smaller than you, eating that little and exercising:

    https://community.myfitnesspal.com/en/discussion/10761904/under-1200-for-weight-loss/p1

    Will that happen to you? Odd are that it won't . . . but the chance isn't zero, and it's a life-ruiner if it does.

    Intermittent fasting (IF) is fine. Calorie limitation is fine. Both, as long as either/both are within reason.

    Beyond that, what do you want to prove? It's good to be tough and determined, exercise your will power. It's also good to be smart, preserve robust good healthy by staying on a path of thriving. You're getting advice here from multiple people who've been successful at both weight loss and long-term weight maintenance.

    Let us know how it's going, over time, maybe? I hope you'll be successful in both weight loss and health terms, no matter what route you choose, sincerely.