Some Answers About Genes, Environment, Obesity and Maintenance
This ended up being very lengthy, but I hope you all take the time to read or skim it because this is really important information about maintenance. :)
I attended a lecture this week given by Rudolph L. Leibel, head of Molecular Genetics at Columbia Medical School, titled Mechanisms For Body Weight Regulation. We’ve had several discussions here in Maintainers about hormones, weight regulation, and metabolic rates after losing weight and he answered some of our questions. I can’t say these were answers that I wanted to hear, but this is really important stuff, so bear with me and I’ll try to summarize.
The first part of the lecture was all about research into how our bodies regulate their weight. I don’t want to go into the science of it in detail – much of it was over my head! – but the overall picture is that we have a complex system of hormones that act on our brains which control appetite, metabolism, and fat storage. We’re born with certain genes that generate and control these hormones which are then affected by the environment in which we live. His research shows that obesity is about 60% a genetic predisposition with about 40% attributable to our toxic food environment (the way we eat and live today).
Here’s the deal – genetically, we obese (or formerly obese) are the survivors. We’re evolutionarily selected to live in times of famine, when food was scarce and we had to work hard to find it. Think prehistoric times, when dinner meant stalking a woolly mastodon for a week before you could kill and eat it. Then contrast that with how we live now, when dinner means picking up your cell phone and ordering pizza. Food today (often calorie dense) is readily available and requires virtually no work to get it. Our genes are evolutionarily adapted to hoard calories as fat and use them very efficiently. So this system works beautifully if you’re a caveman, but not so well if you work in an office cube.
What this means is that it’s easy for many of us to get fat – not news to most of us. It doesn’t mean that obesity is preordained or that it HAS to happen – that’s still determined by our environment, which boils down to what we eat and how we live.
The second part of the lecture was the reason why I was there – how do we apply this scientific knowledge to weight loss and maintenance? I’m going to break it down into key points -
It’s Calories In Versus Calories Out: He began the second portion of the lecture by citing the First Law Of Thermodynamics – in terms of obesity, it translates into Stored Body Fat = Food Intake – Energy Expenditure. We here at 3FC mean the same thing when we say that you have to eat less (food intake) and move more (energy expenditure) to lose fat. The science of weight loss all comes down to numbers of calories in and out. Forget all the pseudo-science diet books out there about what to eat and not eat – at the end of the day, it’s nothing but numbers and calories.
Dr. Leibel has a lab at Columbia Medical School where he locks in volunteers for up to 27 months and monitors food intake and energy expenditure. He has NEVER had a subject who hasn’t lost weight on a low-calorie diet. They may plateau for a while, which he says is the body replacing lost fat with water temporarily, but ALWAYS lose fat in the end. So he said that people who say that can’t lose weight despite only eating a tiny amount of calories are kidding themselves about their actual food intake. He says that this formula holds true for everyone - Stored Body Fat = Food Intake – Energy Expenditure.
Metabolisms: It takes 50 calories per kg of LBM to maintain the weight of both obese and normal people (people who have never been obese). It’s important to note that the metabolisms of the obese are identical to normal people. The ‘I’m fat because of my metabolism’ argument was shot down in his lab because he discovered that obese and normal people burn calories at exactly the same rate. Obese people are simply taking in – or burning fewer - calories than normal people and storing the excess as body fat.
Back to the equation Stored Body Fat = Food Intake – Energy Expenditure - the energy expenditure (I’m going to abbreviate it as EE) part is made up of three parts: resting energy expenditure, non-resting EE, and thermic (the digestion of food). Resting EE accounts for about 50 – 60% of the calories we burn in a day, thermic accounts for about 5%, and non-resting EE makes up the remainder. If we take in more energy (calories) than we expend, it’s stored in our bodies as protein, glycogen, and fat.
Our Bodies ARE Different!: This is the part that’s relevant to all of us maintainers. Like we’ve long suspected, our metabolisms ARE slower after we lose weight. Scientific research shows that we have to eat less and/or move more to sustain our weight losses.
Here’s the deal - it takes 50 calories per kg of LBM to maintain the body weight of either a normal or an obese person. BUT … it takes only 42 calories per kg of LBM to maintain the weight of a reduced obese person (doctors and researchers call those of us who were obese and are now a normal weight the reduced obese).
We ARE different! Dr. Leibel said that we reduced obese may LOOK normal on the outside but our bodies are very different on the inside. He said that, in order to maintain our weight, we reduced obese need to eat 15 - 20% fewer calories per day than a comparable person – same height, weight and gender etc – who never was obese.
Why? The difference in calorie needs comes ALL from changes in NON-resting energy expenditure. The resting rate is unchanged. But our muscle efficiency increases by 15% after weight loss, so we become more efficient in using energy in exercise and everyday activities. And so we burn fewer calories per pound than either a normal weight or an obese person. It’s completely measurable in a lab – all you have to do is put the reduced obese person on a stationary bike and measure energy expenditure. We aren’t going to burn as many calories as normal people do. In practical terms, it means that when you’re at the gym on a treadmill, the person next to you is going to be burning 15-20% more calories than you do even is she is exactly the same height, weight and age (so long as she never was fat). Wonderful, eh? :p
Leptin Levels: The scientific reason for this change in metabolic rates between normal and obese and reduced obese persons has to do with leptin levels (a hormone). If you google Leibel and leptin, you’ll find a lot of scientific articles about his research that explains it all much better than I can. Currently Dr, Leibel is experimenting with giving reduced obese small doses of leptin to restore its level to that of normal and obese people and it seems to reverse this metabolic slowdown. Unfortunately, it’s not anywhere close to being released as a treatment for weight maintenance (he emphasized that it wouldn’t help for weight loss; it only works for maintainers).
My Thoughts On What This Mean For Us Maintainers: Wow! This is the scientific validation of what I think many of us have long suspected and it’s a reason why it’s so hard to maintain a weight loss. Our own personal experiences and National Weight Control Registry statistics show that we have to eat fewer calories and/or exercise more than normal people in order to maintain our weight losses. Now we know that it’s a FACT and we know why – our non-resting EE slows down by 15 – 20%. Our metabolisms weren’t slower when we were obese but they are genuinely and measurably slower now that we’ve lost the weight. We’re fighting against our own bodies wanting to get fat again.
I went up to Dr. Leibel after the lecture (and waited while he talked to all the MDs and PhDs) and introduced myself by saying that I had a little bit of a different perspective on the issue. I told him that I was a member of the NWCR myself (he had discussed it), told him about our Maintainers group at 3FC, and said that we’re LIVING his research. One of the questions that I asked was - would this slowed down metabolism ever change? Would our bodies adapt to our new weights and our metabolisms ever return to normal? (I was thinking about our Karen here, who’s maintained her weight loss for 15 years) He said no, that the lowered leptin levels were permanent. It’s our bodies' way of trying to make us eat more and get fat again.
But he emphasized that it IS possible to maintain a large weight loss – it’s just a little harder for us to maintain our new normal weights than for people who never have been fat (again, not news to any of us). All these hormones and body weight regulations can be defeated by monitoring our calories in versus calories out because – remember - it’s all numbers. OK, our energy expenditure side of the equation is a little slower than normal people’s. But we still can maintain our weight losses by eating a little less or moving a little more – eating about 15 – 20% less or exercising about 15 - 20% more than normal people.
I sat there with my mouth hanging open for an hour and a half while I listened to all of this. I always suspected that it was all true, but here was the proof. On the one hand, it’s kind of depressing but on the other, I realize that nothing’s changed. Honestly, we’ve all puzzled this out for ourselves already, right?
In mulling all this information over, I’ve got several thoughts:
Please anyone - maintainers and those who are still losing - post your thoughts, opinions, comments, and questions. This is the physical framework in which we're going to live for the rest of our lives and I think it's so important to understand and adapt to it.
This is IMPORTANT STUFF. I hope everyone here at 3FC gets a chance to read and ABSORB this info.
I think for me, it's something I've kind of known (subconciously) all along. I always thought as a pre-pubescent girl - drinking my Diet Coke while my three skinny, gorgeous sisters were eating Baskin-Robbins - that it was SO not fair...
But ya know...life and genetics deals everyone a different set of cards and we should all play ours with an eye towards maximum quality of life. Even though a lot of the time I've had to pass up what 'everyone else' is having - still it's WELL worth it to me. Life not-fat is SO much better than my 'previous' life of sitting at home with the TV and the contents of the fridge...
Anyway...he didn't sit on his butt and moan about how unfair life was to him. You take the cards you're dealt and do the best you can, with a POSITIVE ATTITUDE :) That's my opinion anyway...
Therefore, the diet’s not ever going to be over – we’re going to have to eat thoughtfully for the rest of our lives in order to defeat our bodies’ biochemical mechanisms to regain fat.
The worst possible way to maintain a weight loss would be to try to eat intuitively because our bodies will be cueing us to eat more with lowered leptin levels – we need to eat non-intuitively to outwit our bodies' desire to return to obesity.
The times I've attempted to 'eat intuitively' have been an utter failure for me - resulting in weight gain which I had to take off (only like 5-10 lb but that's because I stopped before gaining anymore). I have read the books about the topic and overcoming overeating and all that, and I can see in THEORY where it might make sense...but it just doesn't work for me. The closest I can come to 'eating intuitively' is to have a fairly limited mental 'staple food list' of stuff that I keep around the house - fruits, veggies, skim milk, oatmeal, eggs, lean meats, light salad dressing, light yogurt, and so on. There's no way I could keep, say, a package of Oreos or Chips Ahoy around the house - for me a bought cookie is an eaten cookie (besides...neither I nor Jim NEEDS that crap around the house - there's enough of that floating around the office! :lol: ) - even if I bought those new 100-calorie snack portions that I've seen in the stores, they'd likely be GONE in a flash. I'm pretty much a sugar addict - I've never been able to eat 'just one cookie' - it's an all-or-nothing deal for me. I'm not sad about it - I have SO MUCH joy and stuff happening in my life that I'm not going to let myself get all depressed about freakin' COOKIES. :rolleyes:
So the 'diet' is never over...that's not a problem. I LIKE my staple foods. I think that ATTITUDE is a major 'make or break' factor with maintenance. Accentuate the positive! :D That's my motto anyway ;)
Sorry I'm rambling...
But Meg...this is GOOD STUFF!!! And you know, I think that KNOWLEDGE is a huge key. It might not be what people WANT to hear but it's IMPORTANT to know this!!
So...like I think we've said over and over and over and over and over again...find a 'diet' that's not a fad/crash/one time thing...something that's a LIFESTYLE CHANGE...make up your OWN 'diet' - the information on good nutrition and exercise is out there, easy to find - starting right here at 3FC - start exercising - even if you can't afford a gym, get out those old Keds or splurge on a pair of comfortable athletic shoes, grab a pedometer and start WALKING - if it's raining go to the mall and walk and then take it from there.
You know, when I was 265 lbs in 1990 and I couldn't even go up a flight of stairs without stopping for breath - in my big tent-like knit cotton Lane Bryant dress which was my outfit of choice at the time (because I could just slip it over my head and it hid my body like a tent) - THAT's when I decided it was time to CHANGE, and I started by going out the door and walking around the block. That one step lead to another...and now I'm here today, fit, healthy, and HAPPY... :)
Sorry to ramble...off to the gym with me!
Wow, Meg! This explains so much. Not sure whether to use the smiley or frownie face. :dizzy: It certainly validates my experience. Based on my measured BMR, and my carefully tracked food intake and activity levels, I simply should have disappeared by now. However, I'm very steadily maintaining on about 1400 calories a day and a lot of exercise.
This raises so many more questions. How big a weight loss causes this to happen? Is the drop in metabolic rate linear with the amount of weight lost? How does age at which the weight was lost affect this? How does rate of weight loss affect it? How does repeated weight loss affect EE? and so on....
Thank you ;)
Off to do 20% more cardio,
Weightlifting To Raise Our Lowered Metabolisms?
OK, so I was kicking all this info around in my head while I was doing cardio this AM (and burning 20% fewer calories than everyone else …grrr… :devil: ) and thinking about what this means in the real world. Is there any way that we can RAISE our metabolic rates that have been lowered by losing weight? Dr. Leibel says that small doses of leptin will do the trick, but unless someone’s got a leptin lab in their basement, that’s not available to help us out. Maybe someday, but not today.
Then I remembered the numbers that he had on the slides during his presentation: normal and obese people need 50 calories per kg of LBM to maintain weight as compared to the reduced obese, who only need 42 calories per kg of LBM. He didn’t say for sure, but I’m assuming that LBM = Lean Body Mass. LBM is your total body weight minus the number of pounds of fat on your body – it’s how we determine our body fat percentages.
Here’s my thinking – if we increase LBM, then we increase the number of calories that we can eat in a day and still maintain our new weights, right? More kilograms of LBM that need those 42 calories of energy mean that we can eat a little more or exercise a little less without gaining.
How do we increase our LBM? By adding muscle to our bodies. Every additional kilogram (not pound) of muscle in a normal weight person will burn an additional 50 calories per day, according to Dr. Leibel’s research. For us reduced obese, with our lowered metabolisms, every additional kilogram of muscle will still burn an additional 42 calories a day. So we want to add muscle in order to be able to burn more calories.
How do we add muscle? By lifting weights. Strength training, bodybuilding, resistance training, toning, weight lifting, whatever you want to call it – it’s all the same thing. Lifting weights builds muscle. More muscle increases our LBMs. More pounds of LBM mean that we can eat more food and continue to maintain our new weights. It’s the only way that I can think of to overcome the lowered metabolism caused by weight loss.
For more info about how to get started in a weight lifting program, visit our Ladies Who Lift forum here at 3FC.
And let’s all head to the gym! :strong:
Yup, I agree with you 100%. :coffee: But, (and you knew there would be a but, otherwise why post :devil: ), there is a point where you just can't add enough "more muscle" to make up for mindless or just plain too much eating.
Since starting to lift heavy about 4 years ago, I've added about 6 pounds of LBM while losing 54 pounds of scale weight. Since most of us are in the age group where we are losing muscle at about 3 pounds per decade unless we are actively rebuilding it through strength training, I think the muscle building is a must just to maintain our health (muscle protects against osteoporisis, helps regulate blood pressure, glucose and sodium levels), not just to eat a little more. Those 6 more pounds of LBM buy me about a 1/2 a cup of cottage cheese and a half a cup of oatmeal a day- which is what it takes to maintain them. Not a burrito with extra cheese or a bagel or a doughnut!
99% of us just don't have the right hormones or enough of them to pack on enough LBM to chow down with the big boys! And I doubt most of us would really want the look of enough muscle to eat 2500-3000 calories a day. :strong:
BUT (there I go with another but) those 6 extra pounds of muscle are enough to keep my bones much stronger than my mother's, who has severe osteoporosis, give me nicely shaped arms, and very strong legs and back. Not to mention my butt. :o
Mel (who has seen enough of the gym for this week)
Hi Meg and Mel,
Thanks for the info ! Really good stuff from both of you, I also thought "but you can raise your BMR with weightlifting" and then right there was Meg's post about the same and mel's post alerting me to the fact that it does not buy you strawberries with icecream everyday.
So for me I go back to my personal way: as eating less (up to a certain level) is easier than burning of the excess with endless hours of cardio, I am also on the side of being carefull about my intake. It comes creepingly (like a nice glass of wine every day just with the evening meal) but to me these "little habits" are all on the way of gaining weight.
Again, thanks for the great info,
Yeah, Rabbit, Mel was wise to put the brakes on my enthusiasm for weight lifting. :) Muscle building is a wonderful thing for all the reasons that she cites BUT it's not going to buy us the ability to eat the way we used to OR the way other people eat. We're always going to have to eat thoughtfully and moderately and limit our calories, no matter how hard we hit it in the gym. I'm thankful for whatever additional calories my ten pounds of added muscle will burn in a day, even if they're oatmeal calories ( :T - I LOVE oatmeal, with a little Splenda and cinnamon - but I digress ... :lol: )
I've been thinking and thinking about what all this means since Thursday, when I went to the lecture. I've decided that I'm both relieved and a little frightened by the news. I'm relieved because this knowledge about lowered metabolic rates following weight loss makes so much sense and lets me, at least, feel like I'm not a freak if I'm still weighing and measuring food, writing it down, and doing all the things that I know are necessary to keep the weight off for life. But it's a little daunting to know that we have to outwit a biological system perfectly designed to make us regain our lost weight.
But - and this is important! - I want everyone to go back and re-read Karen's (MrsJim's) post. Like she says - this is the hand of cards we've been dealt. OK, now we know precisely where we stand metabolically after weight loss. So what? So long as we all have free will - so long as we're the ones making the decisions about what to eat and whether to exercise - we can CHOOSE to be healthy and strong and fit. We know it can be done - we know that weight loss can be maintained for years and years and years (look at Karen!) - and I dare say every one of us knows exactly what to do to maintain our losses.
My fear is that this info is going to discourage people from trying to lose weight or maintain. Knowing how our bodies work doesn't change anything - weight loss (even massive weight loss!) is possible and do-able for everyone and totally worth the effort! Regardless of the effort it takes to maintain (and like Karen says, it becomes almost effortless as living maintenance becomes an lifestyle - it DOES get easier over time!), losing the weight has been the BEST thing I have ever done for myself in my life! I've never been happier and I've never been healthier. I feel proud of myself, I feel good about myself, and for the first time ever in my life, I like looking in a mirror. :o All simply priceless. And a heck of a lot more rewarding that mindlessly stuffing food in my face. :lol:
Only good and positive changes come from getting rid of all those pounds of fat, I - and all the maintainers here - can assure you. Bottom line - no, it's not easy but it's so worth the effort!
Just a brief post here as deadlines are looming. (What? On a Sunday? Don’t ask.)
Thanks, Meg, for taking the time to go to the lecture and to put together such a coherent summary for us. Very interesting knowledge, as my little sister would have said at age 9. But there’s something in there about terminology which I’d like to get clear so people don’t make the wrong assumptions.
Scientists and medics use a scale of different categories for people’s weight. It’s something like: underweight, normal, overweight, obese, morbidly obese. These categories have precise meanings and aren’t just normal language (where obese = very fat). Now Leibel’s work has been done with obese and reduced obese people, hasn’t it? So, the findings may not be true at all for ‘overweight’ people and it may not even be possible to say that they are just ‘a bit less true’ for overweight people. And not all of us maintainers (and lurkers) are reduced obese; some of us (like me) are in the category of reduced/reducing overweight (to coin a phrase).
Splitting hairs? Perhaps, but I think it’s worth pointing out.
Absolutely right and a very good point to make, SB - thanks! :) I wondered about the same thing myself and want to go look up some of his papers on MedLine to see if I can find some more specific answers about how he structured his research.
Thanks Meg, Mel and Karen for your awesome posts.
Thanks, Meg, for making this incredible information available - in an easy to read format, no less! :) It feels good to read facts that support what I've been experiencing the last few years. According to any internet calculator I've used, I should have been able to eat loads more calories than my measly 1200-1300 I was eating just to maintain. It took a long time for me to accept the fact that I would always feel like I was "dieting" even though I had reached my goal weight.
But, like you've all mentioned, if it takes regular cardio and weightlifting, planning and scheduling my meals, weighing myself regularly, logging my food, counting grams of this and that and passing on pizza and french fries, then that's what I have to do. The tradeoff is beyond worth it. It's a price that I will happily pay for the rest of my life. :D
Thanks again, to all of you. This forum is heaven sent!!
I have to echo the thanks Meg, your posts are always so informative. I agree it is heartening in a strange way to have our own maintenance experiences confirmed.
Weight loss is so full of myths, half truths and theory expounded from anecdotal evidence, a bit of concrete research is more than welcome. I wonder if Liebel's research also debunks the notion of "starvation mode". I have always found the concept of being unable to lose weight because you weren't eating enough difficult to understand. If metabolic change only occurs once obesity has been conquered then is starvation mode a myth?
I also wondered if you were able to find any further information about levels of obesity used in the studies? I note that Mel's top weight of 182 probably meant that she was only ever reached Obesity Level 1 yet she has the same maintenance issues as Meg and myself who were over 200 pounds and probably classed as Level 2. Will Silverbirch, who at 5'4 and 78 kilos was only on the threshhold of level 1 obesity, escape a life of chronic restrained eating?
Although again this is anecdotal evidence I can't help but look at my sister and myself. We have both been overweight. I topped at over 200 pounds whereas she only ever reached 30-40 pounds overweight. Technically as obesity starts at a BMI of 30 she probably was obese but not as obviously so as myself. We are both in our early 40s and thin now but we both have to practice restrained eating. She uses different language to describe her situation "watching what I eat" "cutting back a bit". It appears more casual than my planning and journalling but it is none the less every bit as restrained and careful.
Good questions, Alberta. This study confirms a lot of what we knew anecdotally but raises even more questions. One of my big questions is the effect of age: how does when you lost the weight affect the hormonal change? Both Meg and I were in our mid-forties and in peri-menopause when we lost our poundage. I have 2 clients currently in their early forties who tell me that they were 40-50 pounds heavier when they graduated from college, but lost the weight in their early 20's, and don't have to practice chronic restrained eating. They don't eat mindlessly, but they don't diet or really think about it. Most of us on this board are well over our early twenties (not to insult our few young 'uns....we luv ya!) and are into or headed over the hormonal precipice already. :lol:
Hopefully, this research is just the tip of the iceberg and more questions will be answered. We just need to get Meg into more of those lectures ;)
Meg said << But we still can maintain our weight losses by eating a little less or moving a little more – eating about 15 – 20% less or exercising about 15 - 20% more than normal people.>>
Great post Meg, good reporting. What cheery news to greet the new year!
Keep in mind however that the 15 to 20% deficite that the 'reduced obese' show is only on expended energy, not on resting rate (50 to 60% energy usage) which remains unchanged as you say, nor thermic (5% usage). If I am understanding it correctly (and I do have a low fever), that means 'only' a 15 to 20% reduction on 35 to 45% of our EE, not on the entire amount. Or, rounding off, about a 5 to 9% total reduction in calories consumed, or increase in calories expended depending on the individual.
We know small amounts of calories consistently consumed daily can add up to pounds over the year. 10 cals extra/day = 1 pound over a year. 100 extra = 10 pounds. Assuming a 10% reduction in EE, and assuming 1400 calories/day maintanence level, that would roughly translate to 14 pounds/year possibily gained. Hopefully the scale would tip you off before that happened.
As Fletcher says in 'Thin for Life', to succeed, 'Accept the food facts.', and this one is a real doozey.
Thank you for this information. I have lived it and know that it is true. But it feels really good to have some scientific support. Many times we beat ourselves up when we have a gain from just slight increases in food intake. This has lead to self-destruction for me at times. What am I doing wrong? How come after a small gain it is so hard to take it off? I only tried to enjoy my vacation, how did I gain XXX pounds in a week? Answer: It must be something I am doing wrong.
A big congratulations to all who have succeded against these odds. We are to be applauded. I am saving this information forever.
|All times are GMT -4. The time now is 11:03 AM.|