I have recently seen information about how the resting metabolic rate (RMR) fits into this. You might want to do some web searching, say, at Mayo Clinic or some other medical website.

Resting metabolic rate is how many calories your body burns if you do nothing but lie in a bed for 24 hours. I believe that the general guideline of 1200 calories comes from this concept. I have read that if a person eats fewer calories than their RMR, it does cause the body to try to conserve resources. This is the "starvation mode" that people refer to. But also seems to be true that for many people, RMR is higher than 1200. Someone who is physically active and younger has a higher RMR; someone who is completely sedentary and older may have a lower RMR.

There are lots of calculators on the web, but the actual tests to determine these values for an individual are pretty elaborate. Most calculators give you an estimate of calories burned in a day, which is more than RMR.

Calculators just add and subtract numbers, so an iPod program or even FitDay will give you numbers under 1200 if you have an aggressive weight loss goal. However, FitDay warns you that you are setting calories too low according to that "1200 limit."

We get a lot of response on the 3FC boards when someone is saying that they just can't eat more than 900 calories a day. This is often a case where people start waving the 1200 flag.

I think it's best for people to figure out their own resting metabolic rate in some way, and use that as their lower limit. My own RMR at my current weight is estimated to be around 1275. What I have found by experience is that if I try to eat fewer calories than that for more than a few days, my weight loss is going to stall and I'm going to feel really hungry.

So, Betony, take everything with a grain of salt and find out on your own!

Jay

Originally Posted by rockinrobin:
There's no way on earth for them to accurately predict what any one individual is burning.

rockinrobin: I do agree that these calculators may not be totally accurate, however, just for my ease of mind, I have been keeping track of it anyway. I have compared what a machine at the gym says and what the iPod says and it is ALWAYS within a few calories. So even though they might not be accurate completely, I still sort of have a base to go by....again this is to ease my mind. Just one of the games I play with myself on this journey.

Originally Posted by JayEll:
Resting metabolic rate is how many calories your body burns if you do nothing but lie in a bed for 24 hours.

I think it's best for people to figure out their own resting metabolic rate in some way

JayEll: I understand what RMR is but how do you figure it out?

I guess what I was trying to ask in my original post is....If I am eating 1100-1200 calories a day is that enough if I am burning off 400-600? At the end of the day, I am really only ending up with maybe 600-800 calories. Does that make sense?

Originally Posted by Jacque9999:
I guess what I was trying to ask in my original post is....If I am eating 1100-1200 calories a day is that enough if I am burning off 400-600? At the end of the day, I am really only ending up with maybe 600-800 calories. Does that make sense?

Jacque -- If your are eating 1100-1200 calories, then that is what you're eating. You aren't eating 600-800 calories. I think this is part of what Robin meant when she said she keeps these numbers separate. My advice: don't eat less.

As for the calorie burn estimates, just because the online calculator and the machine are similar doesn't mean they are accurate. When I use an elliptical and wear my heart rate monitor, my hrm generally says that I burn only about 70% of the calories that the elliptical estimates. Now, the hrm is also an estimate, but it's at least based on what my body is doing, rather than general estimates, which is what the others are. Message: don't believe those calorie-burn estimates!

Originally Posted by Heather:
Jacque -- If your are eating 1100-1200 calories, then that is what you're eating. You aren't eating 600-800 calories. I think this is part of what Robin meant when she said she keeps these numbers separate. My advice: don't eat less.

As for the calorie burn estimates, just because the online calculator and the machine are similar doesn't mean they are accurate. When I use an elliptical and wear my heart rate monitor, my hrm generally says that I burn only about 70% of the calories that the elliptical estimates. Now, the hrm is also an estimate, but it's at least based on what my body is doing, rather than general estimates, which is what the others are. Message: don't believe those calorie-burn estimates!

Thanks for your help. You answered my question...I think. I still will do what I am doing since it is working for me!!!

You know I've heard over and over again about counting calories. I have not once counted my calories. It will work for some but not for others. You have to do what works for you. When I'm hungry, I eat. When I'm not I don't. I make healthy choices and exercise. This needs to be something I can live with. Counting my calories every single day...not for me :)

I eat 1200 calories a day simply because I needed a starting place. I added up the calorie value of my most successful weight loss attempt using the old WW exchange program and came up with the number of 1200 calories. When I later discussed it with my doctor he agreed that as long as I ate no empty calories, (100 calories packs of cookies or crackers, or other "diet" junk food) I would be getting enough nutrition. I admit there were days at the beginning where I was full at 1000 or 1100 calories so I stopped eating. I had no ill effects. Later into my plan I started adding calories for the weekend...not really because I needed them, but because I wanted them. SO FAR, I have never had a plateau, I feel better than ever, blood work is great, heart & BP is great. I hope that eventually I can add calories to maintain, but if not I have lived on 1200 calories for many months and am used to it, and am comfortable with it. Some people take an opposite approach and eat large amounts at the beginning and lose very slowly and keep restricting until they finally have to learn at maintenance to live on WAY less than at the beginning of their journey. I guess that is okay too if they want to keep taking away. Seems more like punishment than reward, but whatever works.

Originally Posted by Looking4Change:
You know I've heard over and over again about counting calories. I have not once counted my calories. It will work for some but not for others. You have to do what works for you. When I'm hungry, I eat. When I'm not I don't. I make healthy choices and exercise. This needs to be something I can live with. Counting my calories every single day...not for me :)

Oh yeah. We all have different things that work for us. Understatement.

The thing is, many, many overweight people, myself included and now even that I'm not overweight - we tend to eat even when we're NOT hungry. I know some people can't imagine that, but that is the case. Counting calories, tracking them - keeps me in check. Forces me to eat the "proper" amount to sustain myself and keep to a healthy weight. I personally don't find it a chore or a burden. Not even one iota. What I did find burdensome was the extra weight I was carrying around. Another understatement. ;)

Luckily, there's more then one way to keep to lose weight and keep it off. :)

Originally Posted by rockinrobin:
Oh yeah. We all have different things that work for us. Understatement.

The thing is, many, many overweight people, myself included and now even that I'm not overweight - we tend to eat even when we're NOT hungry. I know some people can't imagine that, but that is the case. Counting calories, tracking them - keeps me in check. Forces me to eat the "proper" amount to sustain myself and keep to a healthy weight. I personally don't find it a chore or a burden. Not even one iota. What I did find burdensome was the extra weight I was carrying around. Another understatement. ;)

Luckily, there's more then one way to keep to lose weight and keep it off. :)

Well said...I TOTALLY FEEL THE SAME WAY!!!!!!:wave::wave::wave::wave::wave:

Just my personal belief here--if you keep exercising to the point where it becomes a way of life, I think it raises your RMR. I'm talking years. At that point, it can be harder to lose more weight because without knowing it, you're going below RMR in your calories eaten.

Of course, if you slack off on exercise, RMR may drop after some time, in the same way.

So, I believe that weight loss is 80% what you eat, and 20% exercise--but the exercise part cannot be skipped. The reason is that in maintaining weight, continued exercise is critical.

No, I have no science to back this up with, but if anyone knows of any studies, I'd like to see links.

Jay

Originally Posted by Looking4Change:
You know I've heard over and over again about counting calories. I have not once counted my calories. It will work for some but not for others. You have to do what works for you. When I'm hungry, I eat. When I'm not I don't. I make healthy choices and exercise. This needs to be something I can live with. Counting my calories every single day...not for me :)

Works for me too. I actually find listening to my hunger and satiety signals to be quite a challenge, and actually harder than calorie counting. But for me, much more satisfying.

Jay, I've seen several studies that say that exercise is the biggest predictor of maintenance success, which may kind of what you're saying. Ann Fletcher cites one such study in Thin For Life, though I don't have the book in front of me right now to give you the details. :)

The kind of exercise that raises RMR is muscle-building exercise. Muscle is the calorie furnace in our body so the more we have, the more calories we burn in a day just by keeping our bodies alive. The statistics I've seen are that we burn 50 calories per kg of lean body mass/day, so adding a kg of LBM will result in being able to eat 50 more calories per day and still maintain and so on. The calories that a pound of fat burns in a day are negligible.

This is the reason why maintaining and increasing our muscle masses is key to successful weight loss and maintenance. Pounds lost in a traditional diet without muscle building exercise are typically about 40% muscle and 60% fat, which results in a decrease in RMR. The only way to sustain and increase our RMR is by preserving and increasing muscle. And we inevitably lose muscle as we age, which is why we older women must, must, must work out with weights! And weightlifting helps to prevent osteoporosis, so it's a win-win situation.

I don't believe that aerobic exercise has the same impact on RMR because it doesn't change your body to enable it to burn more calories the way that adding muscle does. Aerobic exercise is a fantastic calorie burner and of course it strengths our cardiovascular systems, so it too is an essential component of our exercise programs. But I'm not aware of it elevating RMR the way that muscle building exercise does.

My two cents on exercise and maintenance. :)

Meg,

I thought the "1 pound of muscle burns ~50 calories" estimation turned out to be high and that the real number was more like 7 to 11 calories.

I'll try to find the study.

Tyler, I agree that 50 calories per pound of muscle is ridiculously high.The number I used was 50 calories per kilogram of lean body mass. ;)

I got that number from a lecture I attended given by a obesity researcher from Columbia University's School of Medicine, Dr. Rudolph Leibel (if you've read Gina Kolata's Rethinking Thin, he's cited a lot). I know that the numbers are all over the ballpark but figure his are grounded in science. Who knows? I think it's safe to say that pound for pound, muscle burns a lot more calories than fat. :)

Err, kilogram of lbm, yes. I didn't even see that, so sorry!

The data I saw quoted scientific studies (I haven't had a chance to look for them yet) and said a pound of fat burned ~4 calories and a pound of muscle burned ~7-11 calories, an equation very different from what people commonly believe.

But of course the benefits of weight training are, as you pointed out, great (minimizing loss of lean body mass, etc.)