Realities of Weight-Loss Maintenance

Here at DietHobby, I share my own experiences and opinions as I work to maintain a very large weight-loss. I am now in the 7th year of maintaining at normal weight after spending much of my lifetime in morbid obesity.  Those who are interested can see more details in the ABOUT ME section under RESOURCES.  Recently I posted detailed records of my average food intake together with a summary of my weights during those periods. See Records: My Past 8 years. 

One of the things I've personally discovered from my own experience is that weight maintenance is very difficult, and it takes an enormous amount of ongoing, consistent effort.   When I first reached my goal weight, I had some vague idea from things I'd read, that the first 5 years of maintenance were the most difficult, and if and when I could achieve that point, it would become much easier. 

In my own case, I have discovered this not to be true.  Even though the first couple of maintenance years were difficult, the subsequent years became MORE difficult.  Maintenance did not become easier after 5 years, and I can honestly say that here in my 7th year, maintenance is more difficult than it has ever been. 

My detailed records confirm my subjective experience that .... not only do I need to eat fewer calories than the BMR or RMR charts indicate to maintain the same weight, ..... but, when I raise my daily average calorie intake ... even slightly for a brief time, or for a lengthy time period... I gain weight.  However, for the time period of the past 3 to 5 years, I've discovered that decreasing that average calorie intake to the same extent, does not cause a corresponding weight-loss. 

As an example.... if we use conventional wisdom, and assume that an excess or deficit of 3500 calories = a 1 lb fat loss....my detailed daily food-intake and weight records indicate that during the past 3 to 5 years,  if I eat an excess of 3500 calories I will definitely gain 1 lb fat, however, when I eat a deficit of 3500 calories I will NOT lose 1 fat lb.  In actuality, the 3500 calorie calculation appears to no longer be applicable to my body.  Water weight aside, and referring to fat weight only, it appears that it takes far less excess calories for me to gain 1 fat lb, and that it takes a far greater calorie deficit for me to lose 1 fat lb.  During the past 5 years, I've run many personal experiments testing this particular issue (even using different micronutrients), and each time, my results have confirmed this to be true for my own individual body.
Not only is this a frustrating condition, it is one that almost no medical professional addresses.   Probably, this is reasonable, because there is no actual scientific research on formerly obese people who have lost large amounts of weight, and have maintained it for long time periods.  I personally, am a member of the National Weight Loss Registry, and I have discovered how little data exists about this matter.

There's not much information available on this issue, so I was pleased to discover the following article by Dr. Arya Sharma, M.D.

Why Diet and Exercise is Not a Treatment for Obesity

If going on a diet or starting an exercise program resulted in persistent weight loss, we would not have an obesity epidemic.

Unfortunately, as anyone who has tried this knows, maintaining a significant degree of weight loss requires daily dedication, motivation and a limitless supply of will power - nothing short of developing a compulsive obsession.

As readers will recall, the biology of the post-weight loss state is nothing like the biology of someone who has never lost weight. There are countless ways in which the psychoneurobiology, energy physiology and metabolism in anyone who has lost weight are remarkably different from someone ‘naturally’ of that weight.

Simply stated, someone who was 150 lbs and has lost 20 lbs cannot hope to maintain that weight loss by simply eating the same amount of food or doing the same amount of exercise as someone who is ‘naturally’ a 130 lbs.

The 150 lbs person who has lost 20 lbs, to maintain their new 130 lbs, has to actually now live like someone who is ‘naturally’ a 110 lbs; just eating like someone who is 130 lbs but has never lost weight, will simply result in rapid weight regain.

This is why just cutting out a few ‘extra’ calories or walking a few ‘extra’ steps is not an effective or sustainable strategy for maintaining weight loss - for any clinically meaningful weight loss (when indicated) - we are looking at cutting hundreds of calories from the diet and adding hours of serious exercise per week - forever!

A comprehensive and fascinating overview of the fundamental changes that occur with weight loss to ultimately make sustaining this new weight an ongoing challenge, is discussed by Paul Maclean and colleagues from the University of Denver Colorado, in a paper just published in the American Journal of Physiology.

The authors provide a detailed synthesis of data from a wide range of weight loss studies that include studies in clinically overweight and obese adults, in diet-induced, polygenic animal models of obesity, and with dietary (non-surgical) interventions involving an energy restricted low fat diet.

The consistent finding from all such studies is that all individuals or animals in a post-weight-loss state face considerable ‘homeostatic pressure’ that aims to drive their weight back to initial levels.

The paper extensively discusses how changes in biological signals of fat stores (e.g. leptin) elicit profound metabolic and behavioral adaptations.

The key findings of increased hunger and appetite, reduced satiety and substantially increased ‘fuel efficiency’ have very real underlying biological drivers - drivers powerful enough to ultimately wear down even the most persistent dieter.

As the authors point out - persistent dieting is so difficult because it requires maintaining a remarkably large ‘energy gap’:

“Because both sides of the energy balance equation are affected after weight loss, the biological pressure to gain weight is a consequence of both increased appetite and suppressed energy expenditure.

During weight maintenance after weight loss, this energy gap reflects the magnitude of the daily burden that thwarts cognitive efforts to maintain the reduced weight.

Regardless of which side of the energy balance equation is most affected, the energy gap imparts a substantial pressure to eat in excess of the energy requirements.

The magnitude of the energy gap is greatest at the nadir weight after weight loss. Likewise, this energy gap does not dissipate with time in weight maintenance. Rather, studies in DIO (diet induced obesity) models indicate that the magnitude of the energy gap gradually increases the longer they maintain their reduced weight with an energy restricted diet .

The implications from these observations are that the biological pressures may strengthen with time and the amount of lost weight, gradually increasing their perceived influence.”

The paper also extensively discusses some of the lesser known metabolic adaptations to weight loss including profound changes in gut biology that enhance caloric extraction from food as well as alterations in liver function, skeletal muscle and fat tissue that promote weight regain.

While all of this may seem hopeless to readers, the authors actually end on the rather positive note that:

“… only by acknowledging that these homeostatic pressures emerge, we can proactively develop and implement regain prevention strategies to counter their influence. To ensure success, the regain prevention strategies will likely need to be just as comprehensive, persistent, and redundant, as the biological adaptations they are attempting to counter.”

Obviously, it is also important to note, that no ‘weight-loss strategy” actually addresses the many complex reasons why people may gain weight in the first place.

Whoever said that treating obesity was simply a matter of ‘eating less and moving more’ (ELMM) probably also believes that they can live forever by simply breathing less.

AMS
Burlington, Ontario
Maclean PS, Bergouignan A, Cornier MA, & Jackman MR (2011). Biology’s Response to Dieting: the Impetus for Weight Regain. American journal of physiology. Regulatory, integrative and comparative physiology PMID: 21677272

Dr. Sharma’s Obesity Notes
Dr Arya Sharma, M.D.  -   www.drsharma.ca

 I, personally, have proven that it is possible to achieve a large weight-loss and to maintain the majority of that loss for at least  7 years.  However,  it is true that ... for me... this has required  "daily dedication, motivation and a limitless supply of will power - nothing short of developing a compulsive obsession".  I've also found it true that in order to achieve the maintenance of normal weight, my "regain prevention strategies" have had to be very "comprehensive, persistent, and redundant".

I have found weight-loss to be difficult, and maintenance of that weight-loss to be even more difficult.  Nevertheless, for me personally, I find this to be worthwhile, and I intend to continue on with my maintenance efforts.  And, I'm going to do my best to make my continued and consistent efforts as enjoyable as possible.