Is obesity a disease?

Why Is Obesity a Disease?

The American Medical Association (AMA) designated obesity a disease in 2013 and as a result, the idea that obesity is caused by insufficient willpower, lack of discipline, and bad choices began to transform. The headlines, “AMA Recognizes Obesity as a Disease” were catapulted across both academic and mainstream media. Obesity was no longer a conversation topic tucked away in a dusty corner but was instead sprinkled across national news for the public to scrutinize. From “TED Talks” to The New York Timesobesity specialists were asked to “weigh in” on this groundbreaking and somewhat controversial topic and to answer the question, “is obesity a disease?”

Now, four years later, the debate continues. Is obesity a disease? For some, obesity as a disease invalidates the importance of discipline, proper nutrition, and exercise and enables individuals with obesity to escape responsibility. For others, obesity as a disease is a bridge to additional research, coordination of effective treatment, and increased resources for weight loss.

According to Merriam Webster, a disease is “a condition . . . that impairs normal functioning and is typically manifested by distinguishing signs and symptoms.” In defining obesity specifically, one of the most comprehensive definitions is provided by the Obesity Medicine Association in the Obesity Algorithm. Obesity is defined as a “chronic, relapsing, multi-factorial, neurobehavioral disease, wherein an increase in body fat promotes adipose tissue dysfunction and abnormal fat mass physical forces, resulting in adverse metabolic, biomechanical, and psychosocial health consequences.”

Individuals with obesity have an increased accumulation of fat not always attributable to eating too many calories or lacking physical activity. Individuals with obesity experience impaired metabolic pathways along with disordered signaling for hunger, satiety (the feeling of fullness), and fullness (the state of fullness). For many, efforts to lose weight are met with unyielding resistance or disappointing weight regain. This is demonstrated by the follow-up body composition results of contestants on “The Biggest Loser.” As contestants lose even as much as 230 pounds, their body’s response is a slower and less efficient basal metabolic rate. This occurs in an effort to return the body to its previous condition of obesity; it’s a counter-effort by the body that makes weight gain easier and weight loss harder.

The pathology of obesity is vast and varies based on the cause of weight gain. There is not just one type or cause for obesity. Obesity sub-types include congenital, stress-induced, menopause-related, and MC4R-deficient, to name a few. Obesity is related to genetic, psychological, physical, metabolic, neurological, and hormonal impairments. It is intimately linked to heart disease, sleep apnea, and certain cancers. Obesity is one of the few diseases that can negatively influence social and interpersonal relationships.

Why obesity is a disease is becoming more evident as we increase our knowledge of fat mechanics. To successfully confront the obesity pandemic will require attacking the disease and its manifestations, not just its symptoms.

Do you consider obesity a disease? At the end of this Medscape article, you can take a short survey and view the results to find out where you stand compared to other physician specialties.

This blog article was originally written by Dr Melody Covington MD for the Obesity Medicine Association and can be found in their weight management blog section.

what are the causes of obesity?

Obesity is Not Just Calories In and Calories Out. Here’s Proof

Understanding Causes of Obesity

I attended a networking event this past weekend and I had the pleasure of meeting a young physical trainer aspiring to expand his personal fitness brand. I questioned him on his experience with training clients over 300 lbs and he was honest to state that he had never trained anyone this size. He then went on to say, “at that weight it’s all about diet, so I would cut down their calories and tell them to walk for 40 minutes a day”. I smiled and shook his hand to continue through the crowd of attendees but his statement stuck with me for hours and not in a positive way. I certainly understand his approach, perhaps he was thinking that in order to maintain a 300 lb frame the caloric intake would need to be approximately 4200 calories so reduce calories and increase energy expenditure and voila, we get weight loss. The approach is simplistic and works in some individuals but does not account for basal metabolism, hormone balance, or fat regulation. I would caution applying the calorie and exercise equation to a client without more depth, specificity, or validity. We have all witnessed the individual who is working out excessively and eating a restricted diet to only gain or merely maintain weight. Oftentimes these individuals are blamed for cheating on their diet but the truth is, their weight loss plan may just not work for their sub-type of obesity.

Excess calories and a sedentary lifestyle can certainly lead to excess weight but they are not the only causes for weight gain.

There are over 50 varieties of obesity!

My discussion with this gentleman lead me to write this post and share the various types and causes of obesity. The list below is derived from lectures, presentations, and published articles quoting my adopted mentor Dr. Lee Kaplan, MD, PhD and Medical Director of the Massachusetts General Hospital Weight Center Program. I remember the first time that I heard Dr. Kaplan speak, I was in the last weeks of my internal medicine residency in Charlotte, NC and he was explaining the intricate pathways involved in obesity and the disease of obesity. I was fascinated. In all of my medical training I had never heard anyone explain the complexity of weight in this way. It revolutionized the way that I practice weight management and taught me that obesity is so much more than just diet and exercise alone.

Types of Obesity

Genetic/Congenital and Syndromic Receptor or Hormone Deficiency Neurologic Metabolic Lifestyle Related or Induced Other
-Prader-Willi Sydrome


-Bardet Biedl Syndrome

-Fragile X

-Cohen Syndrome

-Carpenter Syndrome

-Albright Osteodystrophy

-Alstrom Syndrome

-BFL Syndrome

-Ayazzi Syndrome

-MOMO Syndrome

-Rubenstein-Taybi Syndrome

-Leptin Hormone Deficiency

-Leptin Receptor Deficiency

-POMC Deficiency

-MC4R Deficiency

-Alpha-MSH Deficiency

-Sim-1 Deficiency

-PC-1 Deficiency

-KSR2 Deficiency

-MRAP2 Deficiency

-SH2B1 Deficiency

-BDNF Deficiency

-trkB Deficiency

-Central -Hypothalamic



-Healthy Metabolic

-Thermogenesis Deficient


-Insulin Induced


-Progesterone Induced

-Psychotropic Induced

-Antibiotic Induced

-Endocrine Disorder Cushings, Diabetes

-Endocrine Disruptor




-Early Childhood


-Diet Dependent

-Exercise Sensitive

-Sleep Sensitive

-Phentermine responsive

-Lorcaserin responsive

-Topiramate responsive


-Bupropion responsive

-GLP-1 responsive

-Bypass surgery responsive

-Bypass surgery resistant

-Gastric band responsive

-Viral Adenovirus

-Peripheral related


Adapted from Presentations by Lee Kaplan, MD, PHD and publication Your Weight Matters, Fall 2016

Chart and Classification is Original ContentCopyright 2017 © Melody Covington MD, Abundant Health & Vitality Inc

Diet and exercise will always be the foundation for weight loss. We are learning so much about obesity and how to treat it. It is time to reject the notion that diet and exercise alone are the cure for excess weight. It is also time to stop overestimating the impact of exercise, it is much more essential for weight maintenance than weight loss. As listed in the chart above diet and exercise are not the only causes of obesity, so it can also no longer be our only treatment.