Does calorie intake far below MFP specified levels harm you?

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RhushiK
RhushiK Posts: 14
in Food and Nutrition
Hi. I'm 20M, attempting for weight loss, and I'm at near about 270 lbs., so yeah have to loose a lot. My dieting and workout are going great, not eating anything fried or such, lots of natural foods, and I'm usually below the MFP specified calorie intake level for weight loss (which without calories burnt due to exercise is 1750) nearing about 1500-1600. However when I do exercise (Weight-training), though I do try to bring my calories back up with some medium-calorie amount foods, my total calories (intake - exercise) come to near about 1300-1400 (I think 1200 is the basic amount of calories required?). My question is whether such a low level of calorie intake for me right now will cause any negative effects? Like decrease in metabolism, starvation mode, etc. Need some advice here..

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  • TeaBea
    TeaBea Posts: 14,517 Member
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    Hi. I'm 20M, attempting for weight loss, and I'm at near about 270 lbs., so yeah have to loose a lot. My dieting and workout are going great, not eating anything fried or such, lots of natural foods, and I'm usually below the MFP specified calorie intake level for weight loss (which without calories burnt due to exercise is 1750) nearing about 1500-1600. However when I do exercise (Weight-training), though I do try to bring my calories back up with some medium-calorie amount foods, my total calories (intake - exercise) come to near about 1300-1400 (I think 1200 is the basic amount of calories required?). My question is whether such a low level of calorie intake for me right now will cause any negative effects? Like decrease in metabolism, starvation mode, etc. Need some advice here..

    Yes- VLCD (very low calorie diets) can be harmful. Are you under medical supervision?

    I don't have your height, but the BMR for a 20 year old male 270 lbs ....at 5'10' your body uses 2075 calories everyday

    http://www.bmrcalculator.org/

    BMR should be your bare minimum.... not 1200. 2075 calories is what is your body would use if you stayed in bed all day....heart, lungs, kidneys.

    When your body needs fuel.....your body will stop nourishing "non-essentials"......hair, muscle, etc.... in favor of fueling your heart muscle. Do you want to lose weight (fat, muscle, hair, etc.).......or just lose fat. Moderate calorie deficit + exercise helps you KEEP muscle mass.
  • lynn_glenmont
    lynn_glenmont Posts: 10,008 Member
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    At 270 lbs your body is going to be able to convert a lot of stored fat to energy every day (there's formula for this, X grams or calories per kg or lb of fat per day, but I don't remember it off the top of my head and no time to look it up), so I think you'll be OK for sheer energy needs. But will it be sustainable? Will you have a hard time meeting all your macro and micro nutrient requirements at the lower calorie budget you've set for yourself? Will you have enough energy to work out? Also, after you've dropped 30 pounds and the weight loss starts slowing, will you be discouraged by realizing you need to reduce your calories even more or accept slower weight loss (that's not because of "slowing your metabolism," it's because when there's less of you, you need fewer calories to maintain). I'm not saying you definitely will have problems in those areas, but a lot of people do. If I were a 20 YOM, I'd take the 1750 and be looking for more. I'm guessing you got the 1750 goal because you told MFP you want to lose 2 lbs a week, but with the extra deficit you're creating, you're shooting for something more like 2.5 lbs a week. I don't necessarily think that's too much at 270 lbs, but some people will tell you it is.
    (I think 1200 is the basic amount of calories required?)

    That piece of advice is usually cited as the minimum for women. I think for men it's 1500?

    Bottom line, try to make sure what you're doing is sustainable, because you have a long journey ahead of you to get to a healthy weight (unless you're REALLY tall).
  • Hornsby
    Hornsby Posts: 10,322 Member
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    You will be fine. Just recalculate every 10lbs or so. With that much to lose, you are fine to go lower for a while. Once you get closer to where you want to be, just up them slowly.

    That's what I did anyway and I seem to be fine...
  • rileysowner
    rileysowner Posts: 8,211 Member
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    1500 is considered the minimum for males, not 1200. I would suggest that instead of going for the largest deficit you can, you instead shoot for a slower pace. Going with a very large deficit will lead to excessive muscle loss which will be much harder than you might think to put back on. Going with a large deficit usually does not lead to a ripped body, but a skinny fat body.
  • navyrigger46
    navyrigger46 Posts: 1,301 Member
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    I don't know your height, but I started at about the same weight as you (264.4, I am 5'11") I was at 1800 calories a day+exercise calories and it sucked. I switched to TDEE and my workouts got substantially better and I continued to lose 1.5-2 pounds per week. I highly recommend you calculate your TDEE and use that.

    Rigger
  • RhushiK
    RhushiK Posts: 14
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    Hi.
    My height is 185 cm (6 ft). So my BMR comes to about ~2200. Hmmmm... seems like I have to make many changes.. Increase calorie intake without increasing carbs and such..

    Thanks guys for the help.. :)
  • jeroenvandijken
    jeroenvandijken Posts: 18
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    you're at 270lbs right? so you still have to lose a lot of weight wich means you need to start at a higher intake then recommended.
    imagine if you've lost 50lbs and you reach a plateau, then what are you going to do? lower calories again? at a new plateau, lower again? nah that ain't gonna work... you need some space to adjust your kcals, also it is a good thing to take a diet break once every 10/12 weeks (eating around maintenance)
  • neanderthin
    neanderthin Posts: 10,006 Member
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    you're at 270lbs right? so you still have to lose a lot of weight wich means you need to start at a higher intake then recommended.
    imagine if you've lost 50lbs and you reach a plateau, then what are you going to do? lower calories again? at a new plateau, lower again? nah that ain't gonna work... you need some space to adjust your kcals, also it is a good thing to take a diet break once every 10/12 weeks (eating around maintenance)
    What your suggesting is that his TDEE will be reduced to 1200 or 1300, no, not going to happen.
  • hazeljordan1974
    hazeljordan1974 Posts: 107 Member
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    Be careful, I wrote a post on my experience of losing weight too fast here - http://www.myfitnesspal.com/topics/show/1130756-cautionary-tale-don-t-lose-weight-too-fast

    It can be very tempting to want to get to the finish line as quickly as you can, to get that body you are striving for, I get it I really do. Sure I have a slim physique now and I wear smaller sized clothes but I am still waiting for my toenails to grow back and my hair is completely knackered still, my skin is starting to improve but it was really bad at one time. So do try to just lose at a sensible rate and eat enough each day.

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