Why is it harder to lose weight for some people than others?

While I do believe that it is calories in vs. calories out, I truly believe that for some people the number of calories burned is more dependent on the number of calories consumed than it is for other people.  I see plenty of posts from people who steadily lose 1-2 pounds per week because they keep their daily calorie deficit at 500-1000 per day, while I see other posts from people like me who lose weight very unsteadily, are lucky to eek out an average loss of a half pound a week, and plateau regularly despite keeping their daily calorie deficit between 500 and 1000.

I learned a long time ago that trying to lose weight eating 1200 calories doesn't work for me.  I'm 5'1", 146.5 lbs (as of this morning), I excercise every day for upwards of an hour, part of which is weight training, and I eat 1600 calories a day.  I've lost about 13 lbs since I started using CC 20 weeks ago, and I'm thrilled with the loss, and while I occasionally get frustrated wondering how long it's going to take to finally reach my goal or wondering when a plateau will finally break, I'm grateful that I've come this far, as that's more than I can say for any previous attempt I've made at losing weight.

So what is it that makes the difference?  I have 2 hypotheses:

1. It's genetic.  Some people's metabolisms are just quicker to slow down in response to an energy deficit.
2. By dieting since I was 13 years old, I've taught my metabolism to slow down and conserve energy when faced with an energy deficit.

I think it may be a combination of the 2 although I'm leaning heavily toward the 2nd reason.  Both my sisters were reasonably slim growing up.  My oldest sister started putting on weight in college, and it just kept adding up after she got married and had children.  8 years ago she joined WW and lost weight pretty quickly and with very little excercise (yoga once a week).  She reached her goal, but has since gained most of the weight back.  My other sister has never really been overweight.  She's excercised regularly since college, but at various times has been between a size 4 and a size 10.  Last year she had gotten up to a size 10 and wasn't happy about it.  She started eating smaller portions every 3-4 hours and the weight just fell off.  There was no calorie counting.  There was no excluding any foods, just portion control and excercise.  Now she's a size 2 - 4.

Unlike my sisters, I was a chubby kid.  My mother encouraged me to start dieting when I was 13 years old.  I wish she'd encouraged me to play a sport instead, but she didn't know any better.  I've tried Jenny Craig, Weight Watchers, and briefly, LA Weight Loss (a scam if I've ever seen one).  I've read so many diet/nutrition/fitness books that at this point I could probably write one.  I'm eye rollingly amused when people offer me diet advice, especially the misguided tips such as, "You have to eat a tub of dry organic lettuce every day."  Calorie counting and excercise is the only thing that seems to work for me, but it is slow going.

So, what do you think?  What are your stories?  Does the weight come off as it's supposed to or do you have to struggle to chip off every pound?

Original Post by legaleli:

I see what you're saying - but it seems so odd... let me explain where I am coming from:

Right NOW - your diet is working - this is great.  You eat so much and you exercise so much and the balance is perfect to optimise your weight loss.  According to you - if you continue to eat what you are currently - and add more exercise - thereby increasing your deficit - you will cause yourself to lose less.  I am not disbelieving you - I am only questioning the process of your analysis ("it's the deficit").  What in your biology would cause you to lose less weight if you increased your activity level?

I excercise a lot, so I'm not sure how realistic it is for me to increase my activity level right now, so I can only base my answer to this on my experience of several years ago.  I was eating 1200 calories a day and according to the elliptical machine, I was burning upwards of 500 calories a day excercising (although I don't completely trust the elliptical for that information), and that didn't include the weight training and ab excercises I was doing.  I had been excercising like this well before I started calorie restricting.  Once I started calorie restricting, my energy level went way down.  I felt tired and sluggish during the day, and I didn't lose an ounce during the 2 weeks I ate that way.  I can't say whether I would have lost any weight had I forgone the excercise because I didn't try that.

I'm sorry I made it sound like it all boils down to "the deficit."  Believe me, I don't think it's that simple.  Just about everything one's body does involves a series of hormonal responses.  I can't pretend to understand the complex web of hormonal responses involved in burning fat.  People make it sound so simple -- if you have a calorie deficit, you'll burn fat and if you have a calorie surplus, you'll store fat -- but it's not that simple.  Every day, throughout the day, we alternate between burning fat and storing fat.  There are hormonal signals that tell the brain that you're hungry or full or tired or energetic, signals that tell the heart to beat faster or slower.  There are hormonal signals that will tell the body to burn fat for energy or muscle for energy.

I do think there is some sort of negative feedback loop in play when the body burns too much fat.  Perhaps it has to do with a drop in leptin levels -- I don't know.  But I think that each person has their own limit on their fat loss rate, and I think there are a lot of different factors that determine that limit, among them weight, height, and gender, to name but a few.  Some people can lose 2 or 3 lbs a week without a problem.  Other people, for many different reasons, find that they are limited to losing less than a pound a week no matter how much they try to increase their activity levels.  The body compensates in other ways.

Obviously there's a limit to how much the body can compensate for.  If you barely eat (as I found out), you do lose weight quickly, but some of that weight will be muscle, even if you excercise.  But when you try to lose weight in a healthy manner, the body sets limits in order to try to keep the status quo.  We evolved to store fat to get us through the leaner times.  When we reduce caloric intake, we are sending signals indicating that there isn't enough food around to properly nourish our bodies, and our bodies try to reduce our energy usage so we'll be able to survive until there is more food available.  To a certain extent, we can try to overrule our bodies by excercising more, and this is something I have to do as I've found that I don't lose weight without excercising, but even that has its limits.

Original Post by dolphinclick:

Original Post by legaleli:

I see what you're saying - but it seems so odd... let me explain where I am coming from:

Right NOW - your diet is working - this is great.  You eat so much and you exercise so much and the balance is perfect to optimise your weight loss.  According to you - if you continue to eat what you are currently - and add more exercise - thereby increasing your deficit - you will cause yourself to lose less.  I am not disbelieving you - I am only questioning the process of your analysis ("it's the deficit").  What in your biology would cause you to lose less weight if you increased your activity level?

I excercise a lot, so I'm not sure how realistic it is for me to increase my activity level right now, so I can only base my answer to this on my experience of several years ago.  I was eating 1200 calories a day and according to the elliptical machine, I was burning upwards of 500 calories a day excercising (although I don't completely trust the elliptical for that information), and that didn't include the weight training and ab excercises I was doing.  I had been excercising like this well before I started calorie restricting.  Once I started calorie restricting, my energy level went way down.  I felt tired and sluggish during the day, and I didn't lose an ounce during the 2 weeks I ate that way.  I can't say whether I would have lost any weight had I forgone the excercise because I didn't try that.

I'm sorry I made it sound like it all boils down to "the deficit."  Believe me, I don't think it's that simple.  Just about everything one's body does involves a series of hormonal responses.  I can't pretend to understand the complex web of hormonal responses involved in burning fat.  People make it sound so simple -- if you have a calorie deficit, you'll burn fat and if you have a calorie surplus, you'll store fat -- but it's not that simple.  Every day, throughout the day, we alternate between burning fat and storing fat.  There are hormonal signals that tell the brain that you're hungry or full or tired or energetic, signals that tell the heart to beat faster or slower.  There are hormonal signals that will tell the body to burn fat for energy or muscle for energy.

I do think there is some sort of negative feedback loop in play when the body burns too much fat.  Perhaps it has to do with a drop in leptin levels -- I don't know.  But I think that each person has their own limit on their fat loss rate, and I think there are a lot of different factors that determine that limit, among them weight, height, and gender, to name but a few.  Some people can lose 2 or 3 lbs a week without a problem.  Other people, for many different reasons, find that they are limited to losing less than a pound a week no matter how much they try to increase their activity levels.  The body compensates in other ways.

Obviously there's a limit to how much the body can compensate for.  If you barely eat (as I found out), you do lose weight quickly, but some of that weight will be muscle, even if you excercise.  But when you try to lose weight in a healthy manner, the body sets limits in order to try to keep the status quo.  We evolved to store fat to get us through the leaner times.  When we reduce caloric intake, we are sending signals indicating that there isn't enough food around to properly nourish our bodies, and our bodies try to reduce our energy usage so we'll be able to survive until there is more food available.  To a certain extent, we can try to overrule our bodies by excercising more, and this is something I have to do as I've found that I don't lose weight without excercising, but even that has its limits.

I see where you are coming from now - and I'm with you.  Though I don't think there is as much variance in biology as many (including you) would suggest - your assertions are both good advice and sound advice.  You probably know that my philosophy is "no pain no gain" - which is admittedly both harsh and ill-advised for long-term constant benefits.

The matter of losing energy because of calorie restriction is a big issue for me as well.  I have been playing with that formula for a while - and stimulants are not the answer.

I am also keenly interested in the issues of leptin optimization.  I chemist/biologist friend of mine has convinced me that the answers are found in unpasteurized wildflower bee honey.

Also, your discussion of catabolism - fat / muscle selection by the body for energy - aka partitioning - I am with you there 100%.

These are three very important matters all connected to diet - but not necessarily connected directly to deficit - but all occurring because of deficit.

VERY interesting stuff.