You will ruin your metabolism!

Ajocal18

Is ruining your metabolism just another weightloss myth like starvation mode, eating clean = weight loss, spot reducing, etc? I have seen several people post that yo yo dieting or eating under calories will wreck your metabolism. Thoughts?

yopeeps025

No. Now a very large deficit over a extended period can slow down what your body burns in a day at rest.

cwolfman13

Yes and no. Crash dieting *kitten* with your hormones, including the hormones that regulate your metabolism...so crash dieting and incessant exercise is going to stress the body out and result in most bodily functions, including metabolism, to function less than optimally.

Yo-yo dieting tends to also destroy lean mass which reduces your basal calorie burn over time.

DaveAkeman

I do believe it is.

senecarr

Generally speaking, it is a concept that doesn't seem to make biological sense.
Where does the loss of calorie burning ability go? Why wouldn't your body just do this all the time - we've already went from walking like chimps to two legs to save a cookie's worth of calories per year, but our body has a power saving mode it only engages after you've starved several times?

cwolfman13

senecarr wrote: »

Generally speaking, it is a concept that doesn't seem to make biological sense.
Where does the loss of calorie burning ability go? Why wouldn't your body just do this all the time - we've already went from walking like chimps to two legs to save a cookie's worth of calories per year, but our body has a power saving mode it only engages after you've starved several times?

loss of lean mass. Hormonal imbalances also result in less than optimal metabolic function...this is why people with medical conditions like PCOS, diabetes, etc have more issues than an otherwise healthy individual losing weight.

rjmudlax13

From what I've read there is a serious debate about this in the scientific community. Interested in hearing what people have to say.

walkdmc

I've yo yo dieted for decades and can still drop 2 pounds a week eating 1800 cal/day, in my 40's. I've had med gem metabolic testing done 3x and each test showed a decent number...around 1700 resting metabolic rate.

That saying hasn't been true for me.

I wouldn't advise yoyoing but I don't belive it's caused significant harm. And my yo yos were 50-ish pounds.

3dogsrunning

I did lose weight with a very strict diet and lots of exercise. I felt like it was very difficult to transition into maitaninance because of it. I do believe there can be negative affects as others have noted above.

fastforlife1

The less a person weighs the lower his/her metabolism will be. So no matter how a person diets if s/he loses 50 pounds his/her metabolism will be slower. Also according to Dr Varady,, who has done a lot of research on this topic, people who were once obese will have a slightly lower metabolism than their weight counterparts who have never been overweight. Sad but true. The only way to counteract this is by building muscle mass to increase metabolism. http://www.eoddiet.com/faq/

yopeeps025

rjmudlax13 wrote: »

From what I've read there is a serious debate about this in the scientific community. Interested in hearing what people have to say.

Well if you look at total percentage of what you lost during your weight loss. Muscle mass would be a factor to saying how much more someone could eat after the weight loss. That why MFP usually preaches resistant training to maintain as much muscle mass as possible during the weigh loss.

Ajocal18

Thanks for all of your replies, I'm not considering starving or yoyo dieting for the record. Just curious.

cwolfman13

rjmudlax13 wrote: »

From what I've read there is a serious debate about this in the scientific community. Interested in hearing what people have to say.

You don't "ruin" your metabolism per sei...but you can substantially suppress it. Look at how anorexics suppress their metabolisms but with some time of reverse dieting, they boost them back up...this is due to hormones re-balancing and eating in such a way as to sustain muscle mass.

This is also somewhat observable with your average dieter. After about 9 months of dieting and losing 40 Lbs I was pretty close to being at a standstill...losing maybe 0.5 Lbs per week tops. I figured my maintenance would then only be 250 calories more than I was consuming at the time (around 2100) which made me kind of sad. But as I went to maintenance and added those calorie back, my metabolism revved back up a bit and I was still losing at 2400 calories...ultimately topping out around 2800 calories. Depending on my activity and time of year, I maintain anywhere from 2800 - 3000 calories per day now.

gothchiq

The way most people think of it, I believe, is a myth. People *can* damage their metabolisms but it takes something fairly drastic for it to be a major thing. I think a lot of people do embark upon their weight loss plan without thinking about body composition. So they lose a fair bit of muscle. Muscle burns calories just existing. To keep your calorie burning potential maximized, it is better to maintain as much muscle as possible while losing weight in fat and excess water. It also is better not to go below 1200 cal, because if you go way too low, you get sluggish and eventually malnourished. Lifting weights and good nutrition help you hang onto muscle mass so as to keep your body composition and your calorie burning potential at their best for your weight. I lost 30 pounds, while lifting, and I thought it would be inevitable that I lose some muscle. Body composition testing revealed that I actually kept it all. Too bad I'm short and middle aged... that in itself keeps my maintenance calories a lot lower than I would wish, but had I not lifted, it would undoubtedly be worse.

CSARdiver

The problem with tracking this from a scientific sense would be to reduce the variables, which would not apply to most people in real life (in vivo). cwolfman13 stated this best in that severe changes will suppress metabolism and trigger hormonal shifts, but very little in biological systems is permanent.

The best research I've seen on this subject is from the US Navy weight loss studies. The study was conducted to get new recruits to improved BMI profiles during the 8 week boot camp as they experimented with caloric intake. The group who maintained the lower, but healthy caloric intake showed the greatest overall loss after 8 weeks. Unfortunately the study is heavily biased as all candidates were young (18-34) and in a completely regimented environment.

Need2Exerc1se

I'm sure you'll get answers for both sides. Personally, based only on a few decades of personal and anecdotal experience (yes, I'm old), I think it plays a minor role. Activity level and genetics has more to do with your metabolic rate than diet, except in extreme cases or where medical conditions are at play.

PeachyCarol

fastforlife1 wrote: »

The less a person weighs the lower his/her metabolism will be. So no matter how a person diets if s/he loses 50 pounds his/her metabolism will be slower. Also according to Dr Varady,, who has done a lot of research on this topic, people who were once obese will have a slightly lower metabolism than their weight counterparts who have never been overweight. Sad but true. The only way to counteract this is by building muscle mass to increase metabolism. http://www.eoddiet.com/faq/

That effect you mentioned is not permanent.

justcat206

cwolfman13 wrote: »

rjmudlax13 wrote: »

From what I've read there is a serious debate about this in the scientific community. Interested in hearing what people have to say.

You don't "ruin" your metabolism per sei...but you can substantially suppress it. Look at how anorexics suppress their metabolisms but with some time of reverse dieting, they boost them back up...this is due to hormones re-balancing and eating in such a way as to sustain muscle mass.

This is also somewhat observable with your average dieter. After about 9 months of dieting and losing 40 Lbs I was pretty close to being at a standstill...losing maybe 0.5 Lbs per week tops. I figured my maintenance would then only be 250 calories more than I was consuming at the time (around 2100) which made me kind of sad. But as I went to maintenance and added those calorie back, my metabolism revved back up a bit and I was still losing at 2400 calories...ultimately topping out around 2800 calories. Depending on my activity and time of year, I maintain anywhere from 2800 - 3000 calories per day now.

It's anecdotal and not scientific but I struggled with anorexia in college - eating well below 900 cal/day and working out a ton. I had very little muscle mass and as I started eating again I'd gain super fast. These days I have been recovered for several years, built up quite a bit of muscle mass and can maintain on closer to 1600 cal/day without much cardio and I'm not a whole lot heavier than my 'skinny' days.

pawoodhull

My metabolism has always been slow. Some people are fast, some slow, just the way it is. The more I weighed, the slower the metabolism. Of course the more I weighed, the slower I moved. A vicious cycle! I've dropped 164 pounds so far so I move faster (more mobile obviously) and I eat healthier foods (clean eating) which also contributes to burning calories "cleaner" if you will, more effeciently. Working out also ups the metabolism. As for starvation mode, I didn't believe that ever, makes no sense from a logical standpoint. And then, when my weight loss stalled my nutritionist looked at my food journal and told me I had put myself in starvation mode by eating too few calories and that's why I stalled. She said to up the calories 100 per day until I started losing again. I did and I did. So now I do believe you can greatly slow your metabolism by under feeding your body. Hope that helps.

KrissyRawrz

I've never heard of that but I'd imagine being overweight for a long period of time is much more damaging anyway

Queenmunchy

justcat206 wrote: »

cwolfman13 wrote: »

rjmudlax13 wrote: »

From what I've read there is a serious debate about this in the scientific community. Interested in hearing what people have to say.

You don't "ruin" your metabolism per sei...but you can substantially suppress it. Look at how anorexics suppress their metabolisms but with some time of reverse dieting, they boost them back up...this is due to hormones re-balancing and eating in such a way as to sustain muscle mass.

This is also somewhat observable with your average dieter. After about 9 months of dieting and losing 40 Lbs I was pretty close to being at a standstill...losing maybe 0.5 Lbs per week tops. I figured my maintenance would then only be 250 calories more than I was consuming at the time (around 2100) which made me kind of sad. But as I went to maintenance and added those calorie back, my metabolism revved back up a bit and I was still losing at 2400 calories...ultimately topping out around 2800 calories. Depending on my activity and time of year, I maintain anywhere from 2800 - 3000 calories per day now.

It's anecdotal and not scientific but I struggled with anorexia in college - eating well below 900 cal/day and working out a ton. I had very little muscle mass and as I started eating again I'd gain super fast. These days I have been recovered for several years, built up quite a bit of muscle mass and can maintain on closer to 1600 cal/day without much cardio and I'm not a whole lot heavier than my 'skinny' days.

Similar to you, I struggled with undereating/ednos from 11-25 and immediately went into therapy when I was pregnant. I ate at maintenance and gained 70lbs blind weighing with my doctors. Your body does adapt, but I can eat 1100-1200 and lose weight now (I'm short and sedentary)