Why is it so difficult to keep weight off?
Apparently, evolution has given us
the mechanisms to gain weight
but not to lose it.

BEFORE indulging over the Holidays, think about what Dr. Ayra Sharma, professor of medicine and chair of obesity research and management at the University of Alberta, Canada has to say about this issue.

How The Hedonic System Ratchets Up Your Weight

“Bill Colmers, the neuroscientist, presented an overview of how the brain affects eating behaviour and regulates body weight.

I was particularly impressed by how Colmers described the respective roles of the hedonic and homeostatic systems in human evolution.

While the hedonic (pleasure seeking) system evolved to help our hunter-gatherer ancestors seek out and take advantage of any highly palatable energy dense foods they happened to come upon, the homeostatic system evolved to protect from wasting away those extra calories that they did ingest.

Thus, according to Colmers, the hedonic system’s job was to make it hard to resist, in fact, make our ancestors to often go to considerable lengths to searching out those rare palatable energy dense foods and then to eat as much of them as possible, whether they were actually hungry or not. They could of course always store those extra calories as fat tissue for later use - a tremendous survival advantage.

In contrast, the job of the homeostatic system was to ‘defend’ those stored calories - in fact, it is designed to regard any accumulation of fat stores as the ‘new normal’ and from then on make sure that this increased level of fatness was maintained (or regained) ever after.

Indeed, the homeostatic system is ‘designed’ to readjust its set point of body weight - after all it has to do this starting from birth as body weight continues to increase as the baby grows into a toddler that grows into a kid and ultimately into an adult.

Unfortunately, the mechanisms that allow the set point to reset to ‘defend’ a progressively higher body weight - generally works in only one direction - after all that is all that is required by nature, where people do not naturally ’shrink’.

Colmers used the analogy of a ratchet to describe how the homeostatic system is designed to defend ever increasing body weights without having the ability to reset itself to a lower body weight even if the person now wants to lose weight.

Once set to a higher weight (e.g. resulting from ‘overindulgence’ driven by the hedonic system or other factors that may promote weight gain), the homeostatic system uses a wide range of mechanisms affecting hunger, satiety, appetite, metabolic rate, etc. to ‘defend’ this weight from then on.

A very helpful analogy I thought, nicely explaining why evolution has given us the mechanisms to gain weight but not to lose it.”

Dr. Arya Sharma, professor of medicine and chair of obesity research and management at the University of Alberta, Canada.

 Previously, I posted an article detailing this ratcheting analogy, for more see:  Set Point

Recently the Stanford University Medical School, Health Policy Forum hosted an event examining the reasons why we get fat and how different diet trends and food policies affect our nation’s obesity rates.

The forum featured a conversation between science writer Gary Taubes and Christopher Gardner, PhD, director of Nutrition Studies at the Stanford Prevention Research Center.

During the discussion, Paul Costello, the medical school’s chief communications officer, talked to Taubes and Gardner about Americans’ misconceptions about food, diet and nutrition, the driving forces behind the obesity surge of the late-80s and the path to a healthier, leaner lifestyle.  Below is a video of that 1 hr 24 minute forum.

We got a very tiny Christmas tree this year, because of our new adopted kitten, Layla.  I found her at the SPCA, where someone brought her after she was abandoned by her previous owner.  She is a tortoiseshell, now about 5 months old, and very, very sweet. I got a book to refresh my knowledge about training new cats, and have been working to Think Like a Cat.

 
My advice:   Gather your own knowledge to support your own decisions, beliefs and unique body, and then do what works for YOU.

I definitely don't believe that one size fits all.

My own body, my own culture (southern-based, blue-collar-to-professional), and my own values make up ME…who I am. I am over 60 years old with a great deal of personal experience with diets, “lifestyles,” “non-diets”, and ways-of-eating, as well as an in-depth knowledge received by a lifetime of reading, studying and by watching others in relation to food, exercise, and weight-issues.

Personally, I have no interest in becoming a vegetarian. I’m don’t feel a need to support or spread a message about going green, low-carb, paleo, organic, buying local, or have any desire to become an activist supporting any other method of food intake that is intended to “save the planet”.

I have no present plans to eat mostly plants, or even to avoid processed foods. I use artificial sweeteners and drink diet cokes without restriction. I’ve studied opposing ideas on these issues, and have run experiments with them, and at this point, my experiences have resulted in the belief that doing any of these things is NOT a solution for my own individual weight-loss maintenance problems.
However, any or all of those things MIGHT work for You.    And, who knows, someday I could change my mind about any of them or all of them. It’s called having an open-mind.

Do THIS with what you see at DietHobby.