A better explanation of how the body controls weight and how weight loss surgery works are the Set-Point Theory or Body Fat Set-point. Setpoint theory may help those seeking to lose weight as well as those suffering from eating disorders get a better understanding.
First developed in 1982 by Gurin and Bennett, the theory asserts that the body adapts to our weight range and sets it as a setpoint or a normal. Body Fat Set-point varies for each person and is affected by:
- Genetic Predisposition
- Environmental Factors
- Developmental History
Scientists believe that the average person has a set point range of about ten to twenty pounds, meaning that the body will resist attempts to change that weight.
Our body defends itself against changes to our set-point weight. That is why diet, exercise, and diet pills are not a permanent solution as they do not change our set point. Bariatric surgery, however, changes the body’s setpoint for fast and permanent weight loss.
How Does Brain Control Your Weight?
The brain plays a major role in the body’s energy balance and ultimately our weight management, like our blood pressure. A signal sent from the intestine to your brain adjusts appetite and metabolism. That is why setpoint is also referred to as the body’s neurohormonal axis.
To maintain the particular weight range our body is used to, the brain adjusts our metabolism and appetite – increases hunger & cravings and reduces satiety & metabolism (Starvation Mode). The reverse will happen if you gain weight – the total metabolic rate increases and the body’s temperature rises to help burn off any unwanted calories.
Metabolic Thermostat or Body Thermostat refers to how metabolism and appetite adjust to weight changes.
As we mentioned, the body recognizes the increased fat level and elevated weight as an ideal and makes it its new setpoint to operate around. Even modest diet restriction to lose weight makes us think we are going through starvation.
When you go on diet,
- The metabolism will slow down to conserve energy. The body will sense a semi-starvation state and will attempt to use a few calories it receives effectively.
- The body may require more sleep; the body temperature will drop, and many women will lose their menstrual cycle. This typically occurs when a woman’s weight becomes too low. Her entire reproductive system will shut down because her body cannot handle a pregnancy safely.
- Ultimately when body fat is lost, the appetite of the person losing weight will increase. Many individuals who diet will also experience the urge to binge eat. This is because the body is asking for more food that is being provided to function well.
Why Diets Fail So Often…
Anyone who has ever tried dieting will know how hard it is to lose weight continuously. This is why! Known as plateaus, this is typically a sign that the body is attempting to fight to retain the weight it is.
For dieters, it’s important to accept the fact that the body needs to be at a particular weight to stop the dieting cycle. The more that someone tries to go below this set point weight range (it may be -5 lbs, -10 lbs, or maybe even -20 lbs), the harder the body will fight to retain its natural weight.
A recent study by The New England Journal of Medicine, by the 95% of obese people who lose weight with a rigorous weight-loss program will regain the weight (or more) within two to five years.
Weight Loss Surgery Shifts Body’s Set Point
Bariatric surgery, known as weight loss surgery, offers the most effective procedures for long-term treatment of obesity, whereas non-surgical dietary weight loss options are not long-term.
Until recently, it was assumed that the restriction produced by weight loss surgery (Gastric Bypass, Vertical Sleeve Gastrectomy, and Lap-Band) is responsible for mechanically restricting the amount of food a patient can eat.
A more logical explanation of the mechanism by which weight loss surgery works is “physiologic.” In bariatric surgery, the individual’s setpoint and as results the internal body processes that control hunger and metabolic rate changes – decreases hunger & cravings and increases satiety & metabolism (Overfed Mode).
Basically, bariatric surgery changes the body’s set point by shifting your neuro-hormonal axis to a lower weight and give you a second chance to maintain this “new set point.”
- Role of set-point theory in regulation of body weight
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