Joel Gurin and William Bennett first developed the set point theory in 1982 to explain why repeated dieting was unsuccessful in producing long-term weight changes in a patient. The set point theory suggests that the human body has a weight range that it is genetically predisposed to maintain.
This natural weight range is called your set-point, and is different for every person. Scientists believe that the average person has a set point range of about ten to twenty pounds, meaning that there is a range at which the body is comfortable and will resist attempts to change that weight.
The set point is maintained by the hypothalamus and the human body uses regulatory mechanisms to keep its weight within the “natural” weight range. For example, if you eat more than you need to maintain your body weight, then typically your body temperature will rise and your metabolism speeds up to burn the extra calories. If on the other hand you do not eat enough to maintain your weight, then your basal metabolism slows down to spare the available calories. Another regulatory mechanism is hunger – if the body is not getting enough energy, you will feel hungrier.
When the body’s set point malfunctions, a person’s typically “normal weight” becomes higher. There are genetic variants that can predispose us to higher or lower body weight set points, but their effects are small. Furthermore, research indicates that certain “obesity genes” can be “turned off” through exercise alone.
However, a number of things can cause the set point to change and sabotage weight loss efforts. Over the long term, excess food and insufficient exercise will override your body’s natural tendency to stay at its set point and lead to a higher, less healthy set point.
Other common causes of set point malfunction are: aggressive and restrictive dieting, which can slow thyroid function and metabolism, illnesses (like chronic fatigue or fibromyalgia), medications (including common antidepressants such as Paxil, Celexa, Zoloft and Lexapro, anti-convulsants, blood pressure medications, anti-seizure or pain medications such as Neurontin or Lyrica), birth control pills, synthetic hormone replacement, and diabetic medications (such as glyburide and Amaryll).
A slow, gradual weight gain will fool your body into thinking that your set point should be higher. Then, when you try to lose weight, your body defends that higher weight, making weight loss more difficult. But just as it’s possible to reset your set point to a higher point, it’s also possible to lower it.
Treatment: The Use of Naltrexone as Treatment
Restricting calories to obtain weight loss isn’t necessarily a good solution, because the body will attempt to defend its set point, whether high or low, by increasing hunger and decreasing its metabolic rate. That’s why most restrictive diets in general will fail in the long term.
There are medications that lower the body’s weight set and the most recent one that has been successfully used is naltrexone. This medication blocks a particular type of opioid receptor and has been used for many years as treatment for a narcotic overdose and to reduce the incidence of relapse in alcoholism and opiate addiction.
At lower doses, however, naltrexone has very different effects. At a very low dose it is an immune modulator and has shown to be effective for autoimmune diseases. At doses higher than the immune modulation doses, it is shown to reduce the body’s set point and cause significant weight loss. The effect is enhanced when used with bupropion (Wellbutrin). In a recent trial, this combination was shown to result in significant weight loss over twice the rate of placebo with an average weight loss of over 17 pounds. Additionally, we have found patients experience improved mood and energy, reduced migraines, anxiety and PMS and increased libido, with no significant side effects.
Other factors to consider that can help to lower the body’s set point include thyroid hormone optimization, consistency in diet and exercise levels, and correct, integrative management of conditions such as chronic fatigue, fibromyalgia, chronic infections, and chronic inflammation.
Set point malfunction doesn’t have to sabotage your weight loss efforts. Contact a doctor or find a program that can help you achieve your goals.