Research Update: Metabolic Hormones Changes After Weight Loss

Long Term Persistence of Hormonal Adaptations to Weight Loss

New England Journal of Medicine 2011: 365:1597-604.

Objective:  To examine the changes in metabolic hormones for up to a year after weight loss.  We need to learn more about why so many people who lose weight gain it right back.

Methods: 50 overweight subjects were enrolled in a 10 week weight loss program which included a very low calorie diet.  At baseline, after the 10 week weight loss intervention, and 62 weeks, the researchers measured leptin, ghrelin, peptide YY, gastric inhibitory peptide, glucagon-like peptide Y, amylin, pancreatic polypeptide, cholecystokinin, insulin, and subjective ratings of hunger.  Each of these hormones has been shown to have an impact on metabolism and/or energy intake.

Results: After the 10 week low calorie diet, subjects lost an average of 29.7 lbs.  Immediately after weight loss, levels of leptin, peptide YY, cholecystokinin, insulin, and amylin were significantly lower and levels of ghrelin, gastric inhibitory polypeptide, and pancreatic polypeptide were significantly higher.  There was also a significant increase in subjective measures of appetite.

One year after the weight loss, there were still significant differences from baseline in levels of leptin, peptide YY, cholecystokinin, insulin, ghrelin, gastric inhibitory polypeptide, pancreatic polypeptide, as well as hunger.

Discussion: It is not surprising that following weight loss, hormones were changed in a way that promoted weight regain.  We’ve known this for some time.  What is surprising is that they remained that way for a full year after the weight loss!

It is evident that our bodies have amazing defense mechanisms to weight loss.  We evolved in times of drought, famine, and food scarcity.  Those who survived to pass on their genes gained weight quickly, and lost it slowly.  This was most helpful during our early period, but this mechanism has really hurt us in the era of unlimited food availability.

It is becoming clear that the reason so many people regain lost weight is not because they become weak and unfocused with their diet and exercise, but because their body very strongly wants them to put the weight back on.  Weight relapse clearly has a physiological basis.

Take Home Message: After you lose weight, you need to realize that your body starts an all out war to put it back on.  Keep your foot on the gas with your diet, cardio, and resistance training programs.  Your weight loss plan is in no way a temporary thing.  In reality, you need to work just as hard to keep it off as you did to lose it.

Product Review: Bodylastics Resistance Bands

Getting to the gym can be a real challenge given our busy lives of work and family responsibilities.  When I was in college and even grad school, there seemed to be plenty of time to get to the gym and enjoy a leisurely workout.  Now that I’m a bit older, time is definitely more limited.  I’ve noticed the same thing with my clients over the years.  Once they hit a certain age, it becomes very hard for them to get to the gym on a consistent basis.   Therefore, as I’ve mentioned before, I’m a big advocate of working out at home. 

Most parts of the body are very easily exercised with a flat bench and some dumbbells.  However, the back can be a bit more challenging to workout at home.  There are several dumbbell exercises that focus on the back, but to really get the variety you want, you’ll need to bring in some other equipment.  I figured I’d use this post to introduce one such piece of equipment: Bodylastics Resistance Bands.  

Bodylastics Resistance Bands are a stackable and adjustable resistance system.  The kit I purchased has up to 96 pounds of resistance, but they also sell kits with more or less resistance.  The system comes with 4 different colored bands of varying thickness that you can combine to produce the exact resistance you need for any exercise.

In addition to the stackable resistance bands, the system comes with handles for both your hands and ankles as well as a door anchor.  The door anchor is the absolute key.  It allows you to attach the system to any door that closes in your home.  If you put it up high, you can simulate high pulley exercises like lat pulldowns.  If you keep the anchor a bit lower, you can simulate low pulley exercises like seated rows.  This adds a completely new element to how you can work your back at home.  Let’s take a quick look at the pros and cons of the Bodylastics system.

Pros

1) Extremely Well Made And Durable:  These will last you a lifetime.  I’ve had mine for 2 years and they are showing no signs of wear and tear.

2) Serious Resistance: I’ve historically been a bit down on resistance bands in general.  I never felt like I was getting the type of resistance that I needed.  Not so with the Bodylastics system.  These feel a lot tighter than other bands I’ve used.  I get a great workout with these.

3) Comes With A Door Anchor:  Great for working the back with simulated high and low pulley exercises.

4) Very Portable:  The system comes with a carrying case that can easily fit in your luggage for when you need to bring your workout on the road.

5) Very Secure Door Anchor: Door anchors tend to make me nervous.  Not this one.  It is solid and it’s going no where, so feel free to workout with confidence.

Cons

1) The only con that I can come up with is the price.  They are a bit more expensive than other resistance bands.  They retail for $54.95, but as of this writing, amazon.com has them on sale for $35.95.

Do I Recommend Bodylastics Resistance Bands?

Absolutely.  These are a great addition to any home gym and will allow you to be much more creative with your workouts.  While they cost a bit more than other bands on the market, the quality of the product easily makes it worth the extra investment.  To learn more about these bands or to pick them up, check out their amazon page (here).