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General question - Risks of Aggressive Deficit?
duckiec
Posts: 241 Member
No significant research/time needed- I was just wondering and thought this group might have some insight.
What are the risks of an aggressive, but not "starvation mode" deficit?
For example, based TDEE #s from a Fitbit, I maintain a 500-1000 calorie deficit/day; usually around 800/day; approx TDEE-33%. If I were to eat at TDEE-20%, I'd have a deficit of around 420/day. Strictly by the numbers, that would be less than 1lb a week loss (assuming 3500 cals/lb). With my current deficit, I'm up/down on the scale- some weeks lose 2-3, some stay the same or go up 1-2. When I go up, it's usually back down, and then some, the following week, and there usually aren't any eating/exercise changes.
I'd think over the course of a month, I'm coming out ahead, as I lose 5+ lbs/month consistently over the long haul, even if I play with the same few pounds a week or two first. But am I really "ahead?"
Does a deficit that's higher, but not overkill (not over 1000/cal/day) still run the same metabolism slowdown risk? Loss of exercise performance? Loss of lean mass? Something I'm not thinking of?
I'm going into a long weekend on a business trip, then prep for an event, where I plan to eat at TDEE or with only a slight deficit most days (and enjoying the one or two I go over!), so it will be interesting to see what happens then, but was curious as to the pros/cons of my usual level.
If this is inadvertently the kind of question that is time consuming or requires a bunch of info to answer, I certainly won't be offended if you lock it up and say go check Google (more). Thanks!
What are the risks of an aggressive, but not "starvation mode" deficit?
For example, based TDEE #s from a Fitbit, I maintain a 500-1000 calorie deficit/day; usually around 800/day; approx TDEE-33%. If I were to eat at TDEE-20%, I'd have a deficit of around 420/day. Strictly by the numbers, that would be less than 1lb a week loss (assuming 3500 cals/lb). With my current deficit, I'm up/down on the scale- some weeks lose 2-3, some stay the same or go up 1-2. When I go up, it's usually back down, and then some, the following week, and there usually aren't any eating/exercise changes.
I'd think over the course of a month, I'm coming out ahead, as I lose 5+ lbs/month consistently over the long haul, even if I play with the same few pounds a week or two first. But am I really "ahead?"
Does a deficit that's higher, but not overkill (not over 1000/cal/day) still run the same metabolism slowdown risk? Loss of exercise performance? Loss of lean mass? Something I'm not thinking of?
I'm going into a long weekend on a business trip, then prep for an event, where I plan to eat at TDEE or with only a slight deficit most days (and enjoying the one or two I go over!), so it will be interesting to see what happens then, but was curious as to the pros/cons of my usual level.
If this is inadvertently the kind of question that is time consuming or requires a bunch of info to answer, I certainly won't be offended if you lock it up and say go check Google (more). Thanks!
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Replies
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This is not a straightforward answer and is very context dependent.
Factors that come into play include:
- leanness
- length of deficit
- size of deficit
- macros (specifically protein)
- effectiveness of strength training routine
- individual hormonal responses
There is no way to tell someone's 'level or tolerance' of a large deficit with any specificity as all of the above, and genetics, play a part. However, the leaner you are, the longer the deficit is and the deeper the cut, the more the risks increase. These include:
- loss of muscle mass
- hormonal disruption (especially if fats are low)
- metabolic adaptation (which you have anyway when dieting to a degree, its just becomes more extreme)
- adherence (low calories = more propensity to binge or fall off the wagon entirely)
- greater chance of weight gain if not reversing properly
- lower energy therefore lower TDEE and worsening gym performance (which also then causes greater risk of LBM loss)
- if calories are very low, then you have nutritional risks as well (less calories therefore less chance to get enough micros and fiber)
For the 'average' dieter, i.e. one not trying to get super lean, the biggest 2 risks I see are those of LBM retention and adherence.
So, the answer is, it depends.0 -
Ah, that makes sense, sorry, didn't mean to ask an a complex question.
I think, too, I'm trying to assess "how bad" my approach might be, when the only way to really tell if it is/isn't will be on the outcome. As I decrease the deficit when I get closer to goal, will I gain more, both initially, and/or keep gaining? Harder to develop LBM? Cause me to burn out and bail? In the long run, does it mean it's going to take me the same amount of time to get, and stay at, my goal weight... and/or the goal after that? I haven't even considered bf % here, either, which I had measured about 20lbs ago at around 38%... no idea now.
Hmmm lots to think about. With all the options (MFP's baseline/eatback method, TDEE-something approach or by Fitbits' goal of X calories deficit/day) it's hard for the "average dieter" to figure out how to best match strategy with intentions, but this helps weigh those options- thanks for the fodder!
Edited to add: I don't want to be the "average dieter." I want an overall healthier, leaner lifestyle and composition. I just want it NOW.
You know, like everyone else. Patience, grasshopper... 0 -
Just adding to what Sara said, there is a limit to how much fat you can lose in a day. I've done some research to see if I could find a concrete figure, but I couldn't. What I recall finding out is that your body has some type of mechanism that doesn't allow any more fat to be oxidized once you hit a certain level.
When you run too low on available energy your body starts to conserve energy by shutting down hormone production, more rapid BMR reduction, and all the things that Sara mentions.0 -
Just adding to what Sara said, there is a limit to how much fat you can lose in a day. I've done some research to see if I could find a concrete figure, but I couldn't. What I recall finding out is that your body has some type of mechanism that doesn't allow any more fat to be oxidized once you hit a certain level.
When you run too low on available energy your body starts to conserve energy by shutting down hormone production, more rapid BMR reduction, and all the things that Sara mentions.
I think Lyle calculated a hypothetical which I can never find, but I believe it was something like 35 cals per pound of fat.0 -
Just adding to what Sara said, there is a limit to how much fat you can lose in a day. I've done some research to see if I could find a concrete figure, but I couldn't. What I recall finding out is that your body has some type of mechanism that doesn't allow any more fat to be oxidized once you hit a certain level.
When you run too low on available energy your body starts to conserve energy by shutting down hormone production, more rapid BMR reduction, and all the things that Sara mentions.
I think Lyle calculated a hypothetical which I can never find, but I believe it was something like 35 cals per pound of fat.
I think it's this study? http://www.ncbi.nlm.nih.gov/pubmed/156156150 -
Tagging for ^^ that study.0
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Just out of the blue here, but I'd add injuries as a risk.
It came up in the general forums today and it happens to be a subject of curiosity to me because of my own issues.0 -
Just out of the blue here, but I'd add injuries as a risk.
It came up in the general forums today and it happens to be a subject of curiosity to me because of my own issues.
I'm not convinced that eating in a larger deficit increases the risk of injury, at least not directly.
Can you elaborate?
I saw the thread regarding whether to raise calories to maintenance during an injury and I think that depends on context. For example if someone was obese I'd still advocate some sort of deficit. Might depend on the present injury too.
Anyways, curious why you think injury risk increases when eating in a deficit.0 -
Just adding to what Sara said, there is a limit to how much fat you can lose in a day. I've done some research to see if I could find a concrete figure, but I couldn't. What I recall finding out is that your body has some type of mechanism that doesn't allow any more fat to be oxidized once you hit a certain level.
When you run too low on available energy your body starts to conserve energy by shutting down hormone production, more rapid BMR reduction, and all the things that Sara mentions.
I think Lyle calculated a hypothetical which I can never find, but I believe it was something like 35 cals per pound of fat.
I think it's this study? http://www.ncbi.nlm.nih.gov/pubmed/15615615
Lyle did a hypothetical calculation rather than taking something directly from a study. However, this may well have been based on this study.
I actually misremembered - it was 31 cals per pound of fat. If I find the discussion I will post.0 -
Just out of the blue here, but I'd add injuries as a risk.
It came up in the general forums today and it happens to be a subject of curiosity to me because of my own issues.
I'm not convinced that eating in a larger deficit increases the risk of injury, at least not directly.
Can you elaborate?
I saw the thread regarding whether to raise calories to maintenance during an injury and I think that depends on context. For example if someone was obese I'd still advocate some sort of deficit. Might depend on the present injury too.
Anyways, curious why you think injury risk increases when eating in a deficit.
SS, I can only speak from my own experience, other anecdotal evidence from other friends, and from Lyle McDonald's comments in regard to "hardening" at maintenance at the beginning of a cut. Obviously, the risk of injury due to a quick reduction in calories vs. a severe reduction in calories vs. how quickly one heals on a deficit as opposed to maintenance, are different things, but I'd call them related.
My injury history aligns perfectly with times when I've either just started cutting calories or have been cutting sharply. I'm curious about this and it's why I responded in the other thread earlier and here. Not meaning to hijack here but I think it is something that warrants consideration when someone is thinking about an aggressive drop in calories.0 -
Just out of the blue here, but I'd add injuries as a risk.
It came up in the general forums today and it happens to be a subject of curiosity to me because of my own issues.
I'm not convinced that eating in a larger deficit increases the risk of injury, at least not directly.
Can you elaborate?
I saw the thread regarding whether to raise calories to maintenance during an injury and I think that depends on context. For example if someone was obese I'd still advocate some sort of deficit. Might depend on the present injury too.
Anyways, curious why you think injury risk increases when eating in a deficit.
SS, I can only speak from my own experience, other anecdotal evidence from other friends, and from Lyle McDonald's comments in regard to "hardening" at maintenance at the beginning of a cut. Obviously, the risk of injury due to a quick reduction in calories vs. a severe reduction in calories vs. how quickly one heals on a deficit as opposed to maintenance, are different things, but I'd call them related.
My injury history aligns perfectly with times when I've either just started cutting calories or have been cutting sharply. I'm curious about this and it's why I responded in the other thread earlier and here. Not meaning to hijack here but I think it is something that warrants consideration when someone is thinking about an aggressive drop in calories.
I don't think you're hijacking at all, and I'm all for discussing this. I'm just not (yet) convinced/in agreement.0 -
Bump to keep0
This discussion has been closed.