Something Most People Don't Seem To Know...

You are somewhat correct in some of your ideas, but you're leaving out some important details in this post.

First, while the body does use energy sources in a kind of "order", it's not a linear process and is dependent on a LOT of factors. As in, even someone with a LOT of fat stores (ie 100+ lbs to lose) will still burn muscle along with fat. It's a small percentage of muscle, but the body cannot access all of the fat stores immediately. And, as those fat stores diminish, it becomes much more difficult for the body to access them quickly for energy purposes. So, more muscle is burned with the fat, because muscle is easier/faster to metabolize in the short term.

And yes, you have to eat less than you burn. However, you have to take into account ALL of the energy your body uses on a daily basis.

BMR is basal metabolic rate, the amount of energy your body requires to maintain basic functions such as breathing and circulation, as if in a coma. Most women have a BMR of at least 1350, up to 1600-1700 for someone who is tall.

Daily activity level is the amount of calories your body burns just doing normal daily activities, such as brushing your teeth, watching tv, cooking dinner, your job, etc. This does not include purposeful exercise. This typically adds AT LEAST 300 calories to BMR (for sedentary.)

These two numbers together represent maintenance calories, what you would eat to maintain your current weight (again, with no purposeful exercise, when using MFP's calculations.) This is the number from which your deficit is created. So, for an average woman, it looks like this (just as an example, with generic numbers):

BMR 1400
Daily Activity 400
Maintenance calories 1800
Moderate deficit for weight loss of about 500
Daily calorie requirements for weight loss - ~1300

If this woman exercises, she requires more calories, because some of those calories she ate were used to provide fuel for the exercise, and those were not accounted for in her daily requirements yet. Her TDEE (total daily energy expenditure) is higher than if she didn't exercise, and her intake must increase, or her deficit will be higher.

Now, your example of intake is sorely inadequate. Even a decent protein bar has only ~200 cals. A cup of plain yogurt is around 150 cals, flavored/sweetened around 200. We'll go with the higher one. 3 hard boiled eggs is about 233 cals. So, total.....

633 cals for the day. This is called a starvation diet and will result in malnutrition, decreased metabolism, loss of lean mass (muscle) and a host of other issues. This provides less than half of the calories required for basic functions like breathing (I don't know about you, but I don't consider breathing optional or a luxury.)

Providing enough fuel is essential. Yes, the average overweight/obese person eats too much. But large deficits, improper and insufficient nutrition, and a starvation diet, are not safe or healthy.

It may help to read these threads that explain how MFP works, metabolism, and why it is important to fuel the body properly.

http://www.myfitnesspal.com/topics/show/186814-some-mfp-basics

http://www.myfitnesspal.com/topics/show/61706-guide-to-calorie-deficits

http://www.myfitnesspal.com/topics/show/10589-for-those-confused-or-questioning-eating-your-exercise-calo

http://www.myfitnesspal.com/topics/show/230930-starvation-mode-how-it-works

*rolls eyes*

you'll learn

OMG - I'd feel like death if thats all I ate.

Surely this is just a fad diet and if in any way you mange to maintain it you'll put all the weight back on once you start eating right again.

Please follow the plan MFP has given you, it works, you only have to see peoples tickers to know that.

Terri xx

sounds like the crap they spew on pro ana web sites. Ana is not your friend.

I think the way our bodies work is slightly more complicated than the original post states.

I'm going to continue to eat my exercise calories just like I have been.
I'm going to continue allowing myself a treat just like I have been.
I'm going to continue eating as many calories as I am just like I have been.

I've lost almost 60lbs doing it the way I am - so I'm doing something right.

well said. i agree completely. (congrats on the weight loss btw!)

Thanks!

AMEN!!!!! I hope the OP reads these responses!

Ok so your 18 with a dim memory of a 5th gradehealth class,touting Healthy eating. I would not follow a goverment subsidized health plan...... go to the library and do some homework, talk to a nutritionest.

This is NOT TRUE. My degree is Nutrition and Exercise Science going into a Doc. Your body uses different forms of energy depending on whether or not you are aerobic or anaerobic state. Which refers to the presence and absence of oxygen, respectively. Most of our cells prefer to get their energy by using oxygen to fuel metabolism. During exercise with adequate fuel and oxygen (i.e., aerobic), muscle cells can contract repeatedly without fatigue. During anaerobic or non-oxygen conditions (i.e., higher intensity exercise), muscle cells must rely on other reactions that do not require oxygen to fuel muscle contraction. This anaerobic metabolism in the cells produces waste molecules that can impair muscle contractions.

Your heart rate/oxygen intake determines what kind of energy you burn at first its fat then when you reach a high heart rate you can into anaerobic (with out oxygen).

You are in danger of burning off you muscle eating so few calories. This is NOT the way to treat your body much less lose weight. You need to eat a healthy amount of whole foods to lose weight, not to much not to little. PLEASE do not pass off information that is false leave the teaching to the professionals PLEASE it can seriously make people very sick.

Excellent reply the OP will hopefully take to heart.

To the OP, enjoy your weight loss while it happens, eventually it will really slow down (several weeks at most). If you continue eating 500 calories a day it will possible even stop. With that there are some rather nasty potential long term consequences both in body and mind. Just for your reading interest try googling the Minnesota Starvation Project and see what happens from extremely low calories. I hope you realize that the people here, and this site are not ignorant of how to lose weight, many of us have done so. Not only that, we have done so healthily and for most of us are healthier, stronger, and more fit then when we started. I can guarantee that on 500 calories a day, you will not be.

This is NOT TRUE. My degree is Nutrition and Exercise Science going into a Doc. Your body uses different forms of energy depending on whether or not you are aerobic or anaerobic state. Which refers to the presence and absence of oxygen, respectively. Most of our cells prefer to get their energy by using oxygen to fuel metabolism. During exercise with adequate fuel and oxygen (i.e., aerobic), muscle cells can contract repeatedly without fatigue. During anaerobic or non-oxygen conditions (i.e., higher intensity exercise), muscle cells must rely on other reactions that do not require oxygen to fuel muscle contraction. This anaerobic metabolism in the cells produces waste molecules that can impair muscle contractions.

Your heart rate/oxygen intake determines what kind of energy you burn at first its fat then when you reach a high heart rate you can into anaerobic (with out oxygen).

You are in danger of burning off you muscle eating so few calories. This is NOT the way to treat your body much less lose weight. You need to eat a healthy amount of whole foods to lose weight, not to much not to little. PLEASE do not pass off information that is false leave the teaching to the professionals PLEASE it can seriously make people very sick.

Excellent reply the OP will hopefully take to heart.

To the OP, enjoy your weight loss while it happens, eventually it will really slow down (several weeks at most). If you continue eating 500 calories a day it will possible even stop. With that there are some rather nasty potential long term consequences both in body and mind. Just for your reading interest try googling the Minnesota Starvation Project and see what happens from extremely low calories. I hope you realize that the people here, and this site are not ignorant of how to lose weight, many of us have done so. Not only that, we have done so healthily and for most of us are healthier, stronger, and more fit then when we started. I can guarantee that on 500 calories a day, you will not be.

Here here, well said!, both of you!

Your goal is 100 lbs. That is too low for most adults. I think your intention is to be too skinny with little regard to your health. It's not worth it. This could lead to a psychological problem - i.e. eating disorder. Steer clear now and get happy with yourself first.

You are entirely right though. We do eat bigger portions than we ought to. Cut your portion sizes to a reasonable amount, but don't cut out food.

You and your body need help. Please see a nutritionist or Doctor.

This. Your body *and* your mind need help.