A Truth that I've frequently considered. 

This is how different
150 lbs can look.

ALL of these women
weigh 150 lbs.

  I am a 5 ft 0 inch woman.
The shortest woman in the picture above is 5 ft 2 inches.

During my years of sharing my online, I've received many comments from women with heights in the 5' 4" to 5' 9' range giving me their opinions about my weight-maintenance stuggles. The substance of those comments have indicated to me that many women simply do not understand, or do not think about, the basic concept of the picture above.

In order to look "normal" weight, shorter women have to weigh less than taller women. In general .... the bodies of shorter women also use less energy (burn less calories) than taller women, and therefore shorter women have to eat far less than taller women.

Additionally, ... in general ... as a woman ages, she burns less and less calories, and many short, elderly woman require very few calories to maintain a "normal" weight.
Food Label information is based on a mythical “AVERAGE” daily requirement  for intake of 2000 calories. Nutritionists also provide that number along with the 1200 calorie number that no one is supposed to go under. Most people consider themselves about average (or better than average) so when they think of daily calorie requirements these are the numbers they normally think about. But these numbers are very wrong for many people.

 More knowledgeable people will use online calculators to determine their basic metabolism rate, and then add the activity factor percentage that they believe applies to them, in order to get an estimate of their own personal daily calorie requirement.

These general truths are also complicated by the fact that the BMR /RMR charts showing calorie requirements for various ages, heights and weights are made up of many different variables that are AVERAGED all together. The calorie requirements given for any specific woman within these charts can often be 10% less than stated.

There can be differences in BMR even when two people have exactly the same lean body mass. Within the studies on which the chart numbers are based, the top 5% of people are using energy 28-32% faster than the bottom 5%.

One 2004 research study reported an extreme case of two people with the same lean body mass (95lbs) … One had a BMR of 1075 calories per day, and one had a BMR of 1790 calories per day. This difference of 715 calories daily is the equivalent to one of these people completing a 10K run EVERY DAY.

Lean body mass is the non-fat portion of the body. For example a "average" 5’4” female weighing 126 lbs would have 95 lbs of lean mass (75%) and 31 lbs (25%) of fat mass. 

Most online calculators use the Harris-Benedict equation and/or the Mifflin equation for RMR. The Harris-Benedict equation was first published in 1919, and is still the most widely used. Since that time there have been numerous studies attempting to improve it, however the most accurate of these studies is the Mifflin equation.

All equations for predicting energy expenditure are only estimates, however, the Harris-Benedict equation typically overestimates by 5% or more.

Also, although Harris-Benedict is called BMR, it is ACTUALLY an equation for RMR, not BMR because the test subjects did not spend the night at the testing facility.

The following chart might be shocking to people who think in the general terms that Nutritionists give about the number of calories required to maintain a normal body weight. 
 I prepared the chart shown here using my own age and height.
This chart shows estimates of my calorie requirements at different weights.
It compares the Mifflin RMR with the Harris-Benedict BMR.

For an estimate of my TOTAL calorie burn based on the chart averages,
see the column which has my sedentary Activity factor (1.2%) added to my Mifflin RMR.

Since my consistent record keeping indicates that my total calorie burn is below average, I also made a comparison of low-average numbers existing within the standard deviation.
This last column most closely matches my numbers in the computer daily calorie records which I’ve kept for the past 8 years.

The calculations most closly matching my records show that eating an average of 1200 calories per day would maintain my body at around 150 lbs.

For my 5’0” elderly body to maintain a weight of 200 lbs, I would need to eat only about 1485 calories daily.

Even my own initial reaction was:  "THAT CAN"T BE RIGHT!" ... but yes, I'm afraid that it is correct.
Notice that EVEN using the total Formula for an "Average" woman of my height and age means eating a 1635 daily average would maintain her at 200 pounds.  To visualize how 200 lbs looks on my 5' 0" body ... add 50 more pounds to the shortest woman on the top picture, and then make her fatter to adjust for making her 2 inches shorter.   

I agree with the following illustration used by Dr. Sharma, M.D. a medical specialist who deals with obesity issues.

Weight Management is like a rubber band.

Weight Loss is pulling on the rubber band.

Weight Maintenance is KEEP pulling on the rubber band.

The individual question regarding our own Weight Management is: 

“HOW MUCH CAN WE PULL ... AND KEEP PULLING?"

This is analogy describes my own lifetime experience. That Truth is especially applicable to my past 7 years of maintenance within the “normal” BMI range, after years of yo-yo dieting up to a high of 271 lbs at 5’0” tall”, with a subsequent total weight loss of 156 lbs. To better visualize this amount, this number was 58% of my TOTAL body weight, which is a similar total amount lost by many of the winners of the “Biggest Loser” television show.

Rubber bands come in different sizes and strength. So do the bodies of people. It naturally follows that the more weight a person loses, the more the "tension of the rubber band".  This is why it usually takes far less effort for someone who loses 10 lbs to maintain that weight-loss, than someone who loses 100 lbs. 

Bodies appear to have a Set Point, which is like a rubber band in it's natural state .. unstretched.  However, it is clear that weight-gain will drive the body's natural Set Point higher. Although most people hope and pray that weight-loss will re-set that altered Set Point back to a lower number, all available evidence indicates that this is a one-way--upward-only--survival path.  Click link for more information about Set Point.

   I’ve been reading a great many things written by Dr. Sharma. At this point, I have a lot of respect for his expertise and point of view.

I like the fact that Dr. Sharma believes that people need to stop beating themselves up for a lack of motivation, and understand that there are very good reasons why they struggle with their weight. He says:

”Everyone talks about eating right and exercising, which is so simplistic. I talk about things like time management and the links between mental health, depression and overeating. And I tell everyone to never trust a diet book that has recipes.”

His advice to other physicians is:

“Telling obese people to ‘eat less and move more’ is like telling someone with depression to cheer up. It’s not that easy. And telling someone that it is demonstrates your lack of understanding.”

Below is a recent video clip of Dr. Sharma.