Is lower metabolism such a bad thing?

[Daves_Not_Here]

Not trying to be intentionally contrarian, but I've noticed there seems to be near universal consensus in the health and fitness community that raising your metabolism is good, and lowering it (particularly your BMR) is bad.  I'm curious what I'm missing (and I'm hoping people here will tell me), because it seems to me that:

• When I google "metabolism and longevity", I find a number of articles, some scholarly, that posit that longevity may be inversely proportional to metabolic rate.  A study of humans who lived 100+ years correlated reduced thyroid function (and consequent lowered metabolism) with their longevity.  Women may outlive men in part due to their lower metabolism.  I can find no citations that refute this idea.
• Intuitively, if I'm able to function on less energy, why is this a problem?  Due to my cardio fitness, I have a lower than average heart rate and blood pressure because my heart and circulatory systems are more efficient.  This is good, right?  So why is having an efficient metabolism bad?  I find I like buying and eating less food.
• Is higher metabolism associated with an elevated ability to rebuild muscle fiber or prevent disease or increase vigor and mental energy?  Or do rest and hormones play a more important leading role, and BMR is a trailing indicator?  Does lower metabolism cause muscle wasting, or is it a symptom?
• I continue to hear how rapid weight loss can cause the metabolism to dramatically "crash", or go into a starvation mode that consumes abnormally less energy than would otherwise be associated with the lighter weight.  Is this really the case, or does a major weight loss result in a completely normal reduction in caloric intake that is so large, it just feels abnormal?
• A follow-up study of The Biggest Loser contestants found their metabolisms were lowered years after having gained back all their weight.  But, other than the contribution to weight gain, were the lowered BMR's detrimental in other ways?
• While I hear the consensus that a higher BMR is "good", I can't recall hearing about specific benefits nor studies that would support them - are there any?

It seems that the primary drawback of a lower metabolism is that it can lead to overeating and weight gain.  But, rather than trying to increase our metabolisms to meet our appetites, could we be better off to lower our appetites to meet our metabolisms?

[tractorlegs]

Frankly, I think we're frequently victimized by overuse and misunderstanding of the terms "High Metabolism" and "Low Metabolism". What is "High" Metabolism? Too many legitimate experts vary so much in their definitions. Also, too many variables are at play in what would make a metabolism high or low. 

Like you, I have a low heart rate because of exercise. Because of that, does that mean I have a low metabolism? But I have increased muscle mass because of my bicycling, and a huge proliferation of mitochondria for the same reason - does this mean I have a high metabolism? Lol the questions could be endless.

Personally, I don't think about it any longer.. Not only does it confuse me, I don't think it's that important in context to my health goals.

[Daves_Not_Here]

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@tractorlegs wrote:

... 

Like you, I have a low heart rate because of exercise. Because of that, does that mean I have a low metabolism? But I have increased muscle mass because of my bicycling, and a huge proliferation of mitochondria for the same reason - does this mean I have a high metabolism? Lol the questions could be endless.

Personally, I don't think about it any longer.. Not only does it confuse me, I don't think it's that important in context to my health goals.

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Ah, cycling.  That would explain the tractor in @tractorlegs 

Agree with you about the confusion.  I'm getting more wary of opinions strongly stated as fact.  Especially in the area of health and fitness.

Going out on a limb:  I'm thinking that a lowered BMR following weight loss could be adaptive in the same way that a lower resting heart rate is adaptive following prolonged cardio exercise.  Just as I'm not trying to increase my resting heart rate, maybe I should appreciate not having to eat so much just to live.

[WavyDavey]

A couple of thoughts:

BMR and resting heart rate are two totally different things. One can have a high BMR and either a high, normal or low resting heart rate.

BMR covers all the normal functions of the body. So if you're trying to lower your BMR, you're also lowering the rate of many recovery and essential functions of the body.

My observation has been that a lower BMR tends to beget a lower BMR. It can lead to a downward spiral where the body has to start to break itself down to combat the caloric deficit that started the whole thing.

A higher BMR gives you more wiggle-room to absorb caloric ups and downs. A lower BMR doesn't have the same cushion, and in a caloric down state, it's probably not going up no matter what.

[UVcat]

Yeah, I kind of agree that the idea that having a "fast metabolism" is good (and that a "slow" one is bad) is mostly because we all want to eat more without being overweight. (I know I do!)

It's an extreme example, but I had a truly very high metabolism (for about a month or two) when I was hyperthyroid as a result of Graves' Disease -- it was definitely the most miserable and unhealthy I've ever been in my life: heart rate extremely high (120+) all the time, even when trying to sleep (which was practically impossible), always hot, constantly shaking, anxious, ravenously hungry a few hours after eating a large meal, etc. Luckily, it was corrected relatively quickly with meds, but horrible while it lasted.

I saw the other side of the coin when my thyroid was completely blocked which switched me to having an unusually low-metabolism (very hypothyroid), which was also not fun but worlds better than being hyperthyroid/high-metabolism. 

Interesting discussion!

-UVc

[tractorlegs]

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@Daves_Not_Here wrote:

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@tractorlegs wrote:

... 

Like you, I have a low heart rate because of exercise. Because of that, does that mean I have a low metabolism? But I have increased muscle mass because of my bicycling, and a huge proliferation of mitochondria for the same reason - does this mean I have a high metabolism? Lol the questions could be endless.

Personally, I don't think about it any longer.. Not only does it confuse me, I don't think it's that important in context to my health goals.

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Ah, cycling.  That would explain the tractor in @tractorlegs 

 Yessir - Hill climbing. [grin]

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[Daves_Not_Here]

@tractorlegs I'm thinking it has to be night and day different climbing hills 60 pounds lighter!  I've found all cyclists either love or hate hills - nobody is neutral.

@UVcat  I was not familiar with Grave's disease - sounds terrible.  It occurs to me - with all of the supposed benefits of higher BMR, I've never heard of prescribing medication to raise it in otherwise healthy people.

Searching for articles on metabolism and longevity, here's one from Harvard Magazine that describes metabolic "stability"  http://harvardmagazine.com/2004/11/a-new-theory-on-longevit.html

Another from Bustle with a number of links to related articles https://www.bustle.com/articles/118002-do-people-with-slow-metabolisms-live-longer

@WavyDavey you had mentioned the body breaking itself down -- is this muscle wasting or are there other systems that are negatively affected?  I've heard this idea often expressed and I admit I'm curious if it's valid, which is why I started this thread.  I just spent 10 minutes googling for articles that support that assertion and can find only lukewarm agreement -- if you have any links to share, that would be great.

[Daves_Not_Here]

Check this out -- this is a graph of Resting Metabolic Rate (RMR) for me, using the Harris-Benedict Equations.  It shows that when I go from 240 to 160 pounds, I will have to eat 500 less calories per day to maintain my new weight.  And, this assumes no "abnormal" slowing of metabolism beyond that which is correlated with lower weight.

[WavyDavey]

Hi @Daves_Not_Here,

I meant both. Once we get to a certain age, muscle wasting becomes less of an inconvenience and more a disease--sarcopenia. Without an active metabolism, where are we going to get the energy to build some muscle to combat the frailty that can accompany aging? 

At the extreme, I read an argument by a man who felt that everyone's heart had a certain number of beats left in it. And when we reach our number, the heart stops working. So he said the best thing was to avoid exercise altogether, keep the metabolism low, and eat very little. Seems a little odd to me, but I suppose it has its logic to it.

I interpret your chart above a little differently.  Assuming your weight loss is not solely from diet (that there's more exercise going on at 160 than 240), you could be burning more calories than before.

[UVcat]

It makes sense to me that BMR would decrease with your mass: you have less body to support, so the energy cost for maintaining the system goes down. The energy expended during exercises like walking or running also depends on your mass.

That said, what I think @WavyDavey might be getting at (and I think this was mentioned up thread as well) is that BMR is not really that relevant, unless you are actually in a coma. TDEE (total energy expenditure) is the amount of energy you *actually* use, and that's the relevant number. This includes all your daily activity and can be much larger than your BMR.

For instance, various estimators put my BMR at about 1400 calories, but my (measured) TDEE is about 2400 with the amount of activity I currently get. That extra 1000 calories is intentional: my fitbit helped me realize that part of why I had gained weight over the course of my 30s was that my daily activity had gone down but my eating had not decreased to compensate. But it also helped me see that I could increase my activity to a level that was sustainable for me (at least for now) and then be able to eat the amount I wanted to eat.

I've heard the "limited number of total heartbeats"-type theory before, and I don't think it's a bad thing to think about. It has a certain logic. But, the people in my life that I've watched get older (all the way to their mid-90s) had better life quality the more they were able to move. And it seems like there's a "move it or lose it" trade-off there. I'm choosing to move it, as long as I can.

Just my $0.02.

-UVc

[Dominique]

This is an interesting conversation. Let’s consider two persons of the same age, gender and height, A and B. Both are 180 lbs, but person A has been maintaining that weight for many years, while person B got there by dieting down from a weight of 250 lbs in a relatively short time. Regardless of whether A and B have a "high" or a "low" metabolism, we know that B will have a lower metabolism than A. This is because of the metabolic adaptation that took place when losing a bunch of weight at a fast pace. We also know it takes a while before metabolism is restored to its "normal" level for a person of that age and size. Since we are in the context of weight loss, this is not an unusual scenario to compare the metabolism of different persons.

This means A will be able to maintain his weight while eating more food than B, all things being equal (same activity level, for instance).  Now, is it better to be A or B? If you don’t particularly enjoy eating food, or if you are in an environment where food is scarce (e.g. a country at war), or you must live on a budget, you’d be better off as B. If, OTOH, you enjoy eating, food is plentiful where you are and you can afford it, you’d probably prefer to be A, right?

Being able to eat more food is like being able to fill in more gasoline in the tank of your car. All things being equal (two cars of the same size), the one with more gas will take you further away, or to the same place quicker.

I think the ideal metabolism is the one that will let you eat the food you want while maintaining a healthy weight and being reasonably active for your own good.

[Baltoscott]

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@Daves_Not_Here wrote:

Not trying to be intentionally contrarian, but I've noticed there seems to be near universal consensus in the health and fitness community that raising your metabolism is good, and lowering it (particularly your BMR) is bad.  ...

It seems that the primary drawback of a lower metabolism is that it can lead to overeating and weight gain.  But, rather than trying to increase our metabolisms to meet our appetites, could we be better off to lower our appetites to meet our metabolisms?

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That drawback is HUGE and is no doubt why most in the health and fitness community would want to try and increase metabolism.  

[Daves_Not_Here]

@UVcat - I agree with your comments on TDEE - I think I look at it the same way.  Regarding the "finite number of heartbeats" concept, I've always taken that as a tongue-in-cheek justification for avoiding exercise (similarly, knees have a limited number of moguls in them which is why I don't ski bumps).  In fact, we have contrary evidence that repeated elevation of heart-rate during cardio exercise prolongs longevity -- a study of the lifespans of competitive cyclists found they live significantly longer than the general population - see https://www.ncbi.nlm.nih.gov/pubmed/21618162

@Dominique -- I agree with your example.  I think person B will struggle more to stay at 180.  But I question if, by losing weight more slowly, Person B would have a significantly easier time staying at 180.  I know that's the general consensus in the fitness and nutrition community, but I'm not aware of any evidence to support it.  Plus, my own limited experience contradicts it -- in my entire life, thinking of the thousands of people I have met and known, I've never once, ever known of anyone who went from 250 to 180 lbs slowly.  Those that weigh 250 either drop the weight quickly or stay fat.  Of the people who drop the weight quickly, they either keep it off or yo-yo.  I have no experience with the "lose slowly" cohort.

[WavyDavey]

@Dominique, that's an interesting analogy about the cars and metabolism. I would say that actually the tanks are the same size in A and B. The "car" with higher metabolism doesn't actually hold more gas. The stomach of a person with high metabolism isn't bigger. It just burns the fuel it has quicker.

I mention this not to find fault in the analogy, but because it brings up a potential disadvantage of high metabolism--that the tank needs filling more often. There's more maintenance.

In my thinking, the ideal metabolism is one that optimizes biological function. It somehow gets equated with weight maintenance, but metabolism is much, much more important than just that aspect.

[Dominique]

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@Daves_Not_Here wrote:

@Dominique -- I agree with your example.  I think person B will struggle more to stay at 180.  But I question if, by losing weight more slowly, Person B would have a significantly easier time staying at 180.  I know that's the general consensus in the fitness and nutrition community, but I'm not aware of any evidence to support it.  Plus, my own limited experience contradicts it -- in my entire life, thinking of the thousands of people I have met and known, I've never once, ever known of anyone who went from 250 to 180 lbs slowly.  Those that weigh 250 either drop the weight quickly or stay fat.  Of the people who drop the weight quickly, they either keep it off or yo-yo.  I have no experience with the "lose slowly" cohort. 

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@Daves_Not_Here: I don’t have any hard data on this, nor any personal experience, but I think you’re right: very few people in real life conditions would lose a large amount of weight in a very slow manner, even if one could reasonably believe (from a physiological standpoint) the outcome would be better (smaller risk of rebounding). Psychology also plays an important role, so being able to see tangible results right from the beginning definitely matters (for motivation). I see from your weight curve in this other thread you’re a drop-it-quickly guy (very impressive drop, btw). What do you think of the alternative method described in the Dreaded Plateau discussion, whereby you neither drop all the weight at once fast, nor do it (again, in one stretch) slowly, but instead do it in chunks, alternating periods of fast dropping (as you have been doing) with periods of maintenance. Takes longer overall than doing it in one stretch, but would supposedly offer better chances of long-term success. I think that’s the approach I would personally favour, if I had the need to drop a very large amount of weight. Do you have a history of yo-yo dieting, or is it your first serious attempt at lowering your weight for good?

[Daves_Not_Here]

What do you think of the alternative method described in the Dreaded Plateau discussion, whereby you neither drop all the weight at once fast, nor do it (again, in one stretch) slowly, but instead do it in chunks, alternating periods of fast dropping (as you have been doing) with periods of maintenance. Takes longer overall than doing it in one stretch, but would supposedly offer better chances of long-term success. I think that’s the approach I would personally favour, if I had the need to drop a very large amount of weight. Do you have a history of yo-yo dieting, or is it your first serious attempt at lowering your weight for good?

@Dominique - Appreciate the questions and indulgence.  I totally agree with you that the psychological benefit of experiencing results far outweighs a theoretical reduced chance of rebound.  I think most obese people feel it's simply impossible to weigh what they weighed in high school, and a dramatic loss gives them hope.  A 12 to 36 month slog is really hard to sustain psychologically, even if it were metabolically more perfect.

At age 40, I discovered low-carb eating and saw how it could accelerate weight loss but didn't understand or act on the rest of the lifestyle equation.  At 50, I got a clue and went from 235 lbs to 170 lbs in 6 months and kept it off for 5 years.  During that 65 lb loss, I had one stall, but I broke it when I realized I had not been reducing my consumption in line with my lighter weight.

Three years ago, I relapsed to old lifestyle patterns and regained the weight.  The relapse had nothing to do with having originally lost the weight quickly.  So now at 58, I'm just repeating what worked for me at 50.  Of course, my goal is to sustain the lifestyle beyond 5 years for the rest of a longer life than was had by my parents and grandparents, I hope.

I find the periodization concept discussed by Dr. Mike Israetel to be compelling.  He makes a lot of sense to me; however, I would alter his approach as follows:  when climbing the Everest of your weight loss, rather than arbitrarily stopping at 10% of your total weight to periodize, just keep pushing forward until you hit a plateau and stop there for a while.  Who knows, you may not plateau and get more quickly to your summit.  I believe the real problems of remaining obese far exceed the theoretical problems of losing weight too quickly.  

In my case, I get a weekly break that may be accomplishing some of the same aims as periodization:  during the week I limit activity and eat at about a 1,500 daily calorie deficit, which is easy when eating low carb high fat.  On Friday, I increase carbs and calories so that I'll be strong for long and hilly bike rides on both weekend days.  Saturday, I eat about 3,000 calories (which sometimes is still a 2,000 calorie deficit).  On Sunday after my ride, I'll eat a recovery meal, and get back to low carb and the deficit.  So my consumption varies greatly, I stay out of a rut, and I get full exercise recovery.  My goal is to get to ski season in fighting weight with good fitness.  Once I get to goal, I'll eliminate the deficit and increase weekly activity as before.  I just need to sustain indefinitely instead of for only 5 years.

Again, thanks for the indulgence!

[Baltoscott]

@Daves_Not_Here -- seems like a pretty good plan.  But you say:

"Once I get to goal, I'll eliminate the [calorie] deficit and increase weekly activity as before."

What is the weekly exercise that you've eliminated and plan to add back after the weight loss ... and why did you decide to eliminate it?

I ask because many people focus on adding exercise as a way to lose weight so that don't have to address their eating patterns, and then have problems maintaining the loss because they cannot maintain the exercise load.  You seem to be eliminating exercise that is already built into your lifestyle during the loss period -- and appropriately lowering calories -- with the plan of adding the exercise back during the maintenance phase.  I don't understand ...

Oh wait, maybe I just connected the dots ... the exercise you are currently missing will come back during ski season?

[Dominique]

@Daves_Not_Here: based on what I’ve read, one week spent at maintenance would be more like a (short) diet break. The full diet break advocated by Lyle McDonald would be longer than that. The physiological and psychological impact of 1) a cheat meal once a week, 2) a 1-2 week diet break and 3) a 1+ month spent at maintenance could perhaps be compared to the impact of one day off from work, a weekend and a long annual vacation (although I know the concept of a "long" vacation is not the same in the US as in Europe) on a working individual: if you have a very demanding job, a long weekend will not provide the same recovery effect as a three-week vacation. The idea of spending long enough at maintenance before going for the next stretch of weight loss is to establish a new, lower "settling point". I think this plays a big role in the long term, not only to facilitate the next stretch of weight loss, but also to prevent rebounding later on.

I agree with you 10% of your body weight before switching to maintenance is arbitrary and could be autoregulated based on how you feel.

I also know there are amazing people like @AuroraKat, @tamado and a few others who have been able to climb the Everest in one go without establishing any basecamps, which is proof it’s possible to achieve a huge weight loss (100+ lbs) without periodizing it. Power to them, it’s all I can say.

[Daves_Not_Here]

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@Baltoscott wrote:

... What is the weekly exercise that you've eliminated and plan to add back after the weight loss ... and why did you decide to eliminate it?

Oh wait, maybe I just connected the dots ... the exercise you are currently missing will come back during ski season?

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@Baltoscott - During the loss period, I'm eliminating weightlifting splits and intense cardio during the week.  Personally, I have a hard time eating at a deficit AND working out with intensity AND getting adequate recovery.  Mornings, I'm doing light cardio for the sanity or a 30 minute session at the gym to hit major muscle groups but no sets to failure.  During ski season, assuming I'm at ideal weight, I'll add the intensity back in, including recovery eating.

My experience is that it's hard to do everything intensely at once (physically and mentally), and if I'm going to lose a lot of weight, then I have to focus on my eating.  I see intense exercise as counterproductive.

I agree with you about people who try to add exercise to mask overeating.  My opinion is we have to adjust our eating so we don't gain during periods of inactivity.

@Dominique:  Thanks for The Full Diet Break link.  I had not previously seen it.  What I take away from it is if I find myself struggling to adhere to a weight-loss regimen, don't just completely throw in the towel and go back to pig-out mode.  Rather, try resting and maintaining for a few weeks and then get back it with renewed energy and normalized hormone levels.