Reduced metabolism by deficit from nutrition vs. exercise

bunnylion

It doesn't matter where your caloric intake comes from, but body composition is most aesthetically pleasing when you are allowed to lose fat slowly and gradually. Adipose tissue isn't the body's first source of caloric replenishment. In fact, when it comes to starvation approaches to dieting, the body's first source of replenishment isn't even glucose; it's free fatty acids and ketones. (i.e) the stuff muscle tissue is made of. The human body is actually designed to hold on to its fat stores once liver glycogen is depleted. So, you can just do exercise if you like, but without adequate food intake, you'll start to lose muscle.

Furthermore, using a starvation or very low calorie diet has actually been proven to increase insulin resistance and cause non-insulin dependent diabetes in obese practitioners.

This doesn't even take into account the adherence rate of those who decide to reduce calories via overexertion. While exercise is good in moderation, it takes HOURS to burn 1K calories. Not many people have that kind of time or can make that a lifestyle commitment. If you can, great, but I'm willing to bet that if you're obese, you will have a hard time making a 180 degree shift to being a gym rat, especially if you're not eating much.

Overall, the easiest and least taxing way to reduce body fat and/or change the body's composition is through a healthy, non-extreme, sustainable diet and exercise program with measurable goals and metrics that support those goals.

References: http://www.nejm.org/doi/full/10.1056/NEJM199706193362507
http://www.jdcjournal.com/article/1056-8727(94)00077-8/abstract?cc=y?cc=y

Please explain why it doesn't matter where my caloric intake comes from?

The rest of your comment states that it is not a good idea to starve yourself. That is not relevant to the question

Your conclusion uses words like healthy and sustainable. Unfortunately there is no consensus on the meaning of these words...

bunnylion

Funny that you mention that, as I have discovered intermittent fasting to work quite well for me.

My original question was aimed at understanding how to lose weight in a way that reduces metabolism the least and therefore makes maintenance easier. Do you know anything about the effects of regular short term fasts on the metabolism.
Studies have shown that a short term fast can even increase the metabolism. But so far I have not heard about any study about long term regular short time fasts....

yarwell

Furthermore, using a starvation or very low calorie diet has actually been proven to increase insulin resistance and cause non-insulin dependent diabetes in obese practitioners.

Odd that a VLCD approach is also used to reverse Type 2 diabetes. Newcastle Diet study.

yarwell

Several studies seem to have gotten to similar results:
I was referring to this article proposing some set point theory: jn.nutrition.org/content/127/9/1875S.full

The set point hypothesis never really got any traction, let alone any experimental confirmation.

yarwell

According to what I've read a 1.5 lb goal for me should be quite reasonable, but if a deficit of 35% is affecting my metabolism in a way that 25% would not, I'd like to know. The study doesn't address that.

It does in a sideways sort of way - the VLCD arm is eating at a huge deficit - 70% initially, 60% at Month 3. The VLCD group get to their weight loss goal quickest and lose the most, the exercise + food restriction group are the slowest. The latter may keep more lean mass and a higher RMR, and this may help them in the long run, depends on how much self control and how you balance the pleasure and cost of eating I guess. Anyway, the results were :-

itsbasschick

i can only tell you for sure how it works for me. i started doing a lot of walking earlier this year without changing my eating at all. i started losing weight at a good clip, felt good and all was well till i injured myself from overdoing it. after a month and physical therapy, i realized i wasn't going to be able to get back to my larger amounts of walking soon, and on may 1 i started logging my food and cutting calories. after the first couple weeks i cut to 1200 net calories, and lost about a pound a week - less than i lost walking, but with my injuries i was limited in how i could exercise.

while a lot of people say that working out isn't the best way to lose weight, i did great on 45 minutes of fairly brisk walking - lost more than i do at 1200 net calories per day. had i not torn my quad in 2 small spots and hurt my hip, i'd be one lean mean walking machine by now, but eating at a deficit has also worked well for me. i have never gone over on my calories since may 1, but it's hard to keep calories down to 1200 while keeping protein up high enough and still having food to enjoy.

when i only eat at a deficit with no exercise, i lose less than a pound a week at this point - exercise makes a big difference. either way, my metabolism seems to be doing what i'd expect - it adapts.

bunnylion

Several studies seem to have gotten to similar results:
I was referring to this article proposing some set point theory: jn.nutrition.org/content/127/9/1875S.full

The set point hypothesis never really got any traction, let alone any experimental confirmation.

Then don't call it set point but adaptive thermogenesis My impression is that adaptive thermogenesis is accepted as a fact by many scientists.

WalkingAlong

It's an interesting topic.

Tangential to it but also interesting are studies that find that when you stop the deficit your burns go back to normal.

http://www.ncbi.nlm.nih.gov/pubmed/11063433?dopt=Abstract
CONCLUSIONS:
"Energy restriction produces a transient hypothyroid-hypometabolic state that normalizes on return to energy-balanced conditions. Failure to establish energy balance after weight loss gives the misleading impression that weight-reduced persons are energy conservative and predisposed to weight regain. Our findings do not provide evidence in support of adaptive metabolic changes as an explanation for the tendency of weight-reduced persons to regain weight."

Thanks for that as well! This is actually part of what I am trying to figure out.

In a documentary it was explained that a person who weighs the same and has the same body composition as another person and one has been that weight their entire adult life and the other one dieted down to that weight, the dieter would need 20% less than the other one.
I find this to be absolutely frustrating, unfair and cruel. :mad:

MFP says once I reach my goal weight I'm going to need 1700 calories to maintain. If the theory is true, than I would actually only need to eat 1360 calories to maintain (which is less than I eat now to lose weight). I'd basically need to stay on a diet for my entire life! .

So now I started to research whether this (set point) theory has a lot of scientific proof or whether there are studies proving otherwise. And if the way of losing weight has any influence... I find losing weight easy but the art is to keep it off, right? So I want to lose in a way that is going to make maintenance as easy as possible.

You might be referring to this:

Long-term persistence of adaptive thermogenesis in subjects who
have maintained a reduced body weight
Am J Clin Nutr 2008;88:906 –12.

ABSTRACT
Background: After weight loss, total energy expenditure—in particular,
energy expenditure at low levels of physical activity—is
lower than predicted by actual changes in body weight and composition.
An important clinical issue is whether this reduction, which
predisposes to weight regain, persists over time.
Objective: We aimed to determine whether this disproportionate
reduction in energy expenditure persists in persons who have maintained
a body-weight reduction of 10% for 1 y.
Design: Seven trios of sex- and weight-matched subjects were studied
in an in-patient setting while receiving a weight-maintaining
liquid formula diet of identical composition. Each trio consisted of a
subject at usual weight (Wtinitial), a subject maintaining a weight
reduction of10% after recent (5–8 wk) completion of weight loss
(Wtloss-recent), and a subject who had maintained a documented reduction
in body weight of10% for1 y (Wtloss-sustained). Twenty four-
hour total energy expenditure (TEE) was assessed by precise
titration of fed calories of a liquid formula diet necessary to maintain
body weight. Resting energy expenditure (REE) and the thermic
effect of feeding (TEF) were measured by indirect calorimetry. Nonresting
energy expenditure (NREE) was calculated as NREETEE
– (REE TEF).
Results: TEE,NREE,and (to a lesser extent)REEwere significantly
lower in the Wtloss-sustained and Wtloss-recent groups than in the Wtinitial
group. Differences from the Wtinitial group in energy expenditure were
qualitatively and quantitatively similar after recent and sustained weight
loss.
Conclusion: Declines in energy expenditure favoring the regain
of lost weight persist well beyond the period of dynamic weight
loss.

As with all studies, this is not ultimately conclusive, but it is sobering.

One might conclude that this is an important reason with one should maintain a vigorous exercise routine following weight loss.

The good news in that study is it says most of the reduction is from less activity, not lower BMR. That part is 100% under our control. And with activity monitors, it's even fairly easy to watch that level over time and adjust it ourselves.

lemurcat12

How do you monitor your TDEE?

I know how much I eat from logging and how much I've lost, so calculate it that way.

(Total calories eaten + pounds lost*3500)/number of days in the time period

chezzac17

Hi ,I joined about a month ago Im on 1200 cals,exercise 4-5 times a week swimming,sometimes I eat cals back sometimes not...and Im very very honest with food cals...and sometimes I go over 1200 cals...dinner ,alchol etc.....I have only lost 1kg and a bit,I want to loose 6 kgs..
can anyone help please Im doing something wrong.....

EvgeniZyntx

When the deficit is lager ? LOL

here's some data from a clinical trial where there are two versions of a 25% deficit - 12.5 exercise and 12.5 less food (CR+EX), or 25 less food (CR) there's also a VLCD on it :-

Thanks for sharing this.

Currently don't have time to read the study so tagging.
My concern is that the predicted TDEE will be based on a weight equation and not an LBM equation.
The branch with exercise will likely lose less LBM and the might explain the differences in prediction versus actual endocrine-driven changes.

meridianova

How do you monitor your TDEE?

I know how much I eat from logging and how much I've lost, so calculate it that way.

(Total calories eaten + pounds lost*3500)/number of days in the time period

i just ran my numbers and came up with something very worrysome... based on that calculation, and compared with the other TDEE calculators available, i'm only burning at 68% efficiency.

my numbers claim that my TDEE is 1,797 per day. i should be at 2,613. so how do i determine what's preventing me from losing weight?

chrisdavey

How do you monitor your TDEE?

I know how much I eat from logging and how much I've lost, so calculate it that way.

(Total calories eaten + pounds lost*3500)/number of days in the time period

THe only issue with that is that you will not lose 100% fat.

stevencloser

Several studies seem to have gotten to similar results:
I was referring to this article proposing some set point theory: jn.nutrition.org/content/127/9/1875S.full

The set point hypothesis never really got any traction, let alone any experimental confirmation.

Then don't call it set point but adaptive thermogenesis My impression is that adaptive thermogenesis is accepted as a fact by many scientists.

Well, that's because it's two different things.
The set point thing was, if I recall correctly, something along the lines of that your body has a certain weight it always wants to go back to if you lose.
Adaptive thermogenesis is your TDEE dropping (slightly, by a few hundred calories at worst as you've seen in the posted screenshots of the studies) after prolonged calorie deficit as a kind of safety mechanism because your body can't tell the difference between actively trying to lose weight and not having enough food to sustain yourself. Which goes back up once you stop being in a deficit.

Scott_2025

Very interesting reading... Thanks everyone for posting.... I have often said losing weight is easy, maintaining weight after reaching goal weight is hard...

bunnylion

Several studies seem to have gotten to similar results:
I was referring to this article proposing some set point theory: jn.nutrition.org/content/127/9/1875S.full

The set point hypothesis never really got any traction, let alone any experimental confirmation.

Then don't call it set point but adaptive thermogenesis My impression is that adaptive thermogenesis is accepted as a fact by many scientists.

Well, that's because it's two different things.
The set point thing was, if I recall correctly, something along the lines of that your body has a certain weight it always wants to go back to if you lose.
Adaptive thermogenesis is your TDEE dropping (slightly, by a few hundred calories at worst as you've seen in the posted screenshots of the studies) after prolonged calorie deficit as a kind of safety mechanism because your body can't tell the difference between actively trying to lose weight and not having enough food to sustain yourself. Which goes back up once you stop being in a deficit.

Yes, you are right. I think there are several takes on both set point and adaptive thermogenesis. I have read that the reasoning behind the set point theory was adaptive thermogenesis. The body adapts metabolism in order to bring you back to your set point or the other way around because of adapted metabolism you return to your set point. An explanation for the set point along these lines was given in the article I posted above.
That's why I threw those two things together, but of course it's better not to do that :-)

yarwell

Currently don't have time to read the study so tagging.
My concern is that the predicted TDEE will be based on a weight equation and not an LBM equation.

It isn't, see the heading "Change in TDEE not explained by change in FM and FFM"

yarwell

THe only issue with that is that you will not lose 100% fat.

isn't that in the use of 3500 already ? (would be >4000 for pure fat)

yarwell

Then don't call it set point but adaptive thermogenesis My impression is that adaptive thermogenesis is accepted as a fact by many scientists.

Adaptive thermogenesis (usually amounts to a candy bar a day) would be one mechanism a set point hypothesis might require to work, for sure.

bunnylion

How do you monitor your TDEE?

I know how much I eat from logging and how much I've lost, so calculate it that way.

(Total calories eaten + pounds lost*3500)/number of days in the time period

Ok, I have been doing the same thing for the past six weeks and so far everything is going as it should :-)
I just want to keep it this way in the long run. From the studies and articles that were posted here it seems that exercise can contribute tremendously. So I'll keep exercise high, keep monitoring TDEE and hope for the best. What more can you do? Fingers crossed!