Misconceptions Around Obesity and Health

Obesity in the medical world is generally defined as a body mass index (BMI) greater than 30 kg/m2 In 2013, the American Medical Association defined obesity as a disease, causing substantial controversy. There is no widely accepted definition of "disease," and many doctors questioned this decision. Some experts also argued that there is no true means of assessing obesity because it is complex and carries with it certain assumptions that don't apply to everyone who is obese. Obesity is a spectrum of phenotypes and contradictions that the medical community is still working to properly define.

The notion of comparing calories in with calories out is a common weight loss equation that is too simplistic to universally apply to obesity. Certain diseases, such as Cushing's disease, cause significant weight gain and obesity, regardless of how rigorously a person exercises or diets. Although decreased activity can be a factor, laziness as the main contributing factor to obesity is an assumption that grew into a misconception.

Surgery can be a life-threatening procedure, and the stress it exerts on the body makes some assume that people who are overweight or obese are more likely to die on the table or experience postoperative complications. After adjusting for related risks, data shows that those with BMI lower than 23.1 were 40% more likely to die when compared to those with BMIs between 26.3 and 29.7, which is considered overweight to borderline obese. Therefore, being overweight may not increase your risk during surgery.

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Doctors have always associated obesity with increased overall mortality risk, regardless of an individual's health. Many studies indicate that obesity is linked to a two-decade decrease in life expectancy. However, a quantitative analysis based on a 30-year-follow-up of 50-year-old white men showed those with moderately low BMI had the same mortality risk as those rated as overweight. In a 10-year study of women, results revealed no relation between BMI and all-cause mortality. Not only do these studies call into question the idea that all forms of obesity automatically lead to higher mortality, but they also show that there is a lack of attention to the health risks of being underweight.

People often assume that an overweight child is going to be an obese adult. However, research shows that there is not a clear line between the two; children and teenagers who are overweight do not necessarily become obese, nor do they have a higher mortality risk. Conversely, being thin in childhood was not a guarantee against adult fatness and may carry a higher risk of adult obesity

Body mass index or BMI has a long history of use, but when it comes to mortality, there is no optimal range associated with longevity. The results of a meta-analysis of close to 30 studies on elderly individuals showed that a relationship between BMI and mortality only correlated in five of the reports. Some results indicated that those with BMIs of 28 and higher had lower mortality risks, so there was no clear relationship between overweight adults and mortality. Because obesity is not a monolithic condition, there is no such thing as an optimal BMI range to reduce individual mortality.

Weight loss is a significant focus in the efforts to solve the increasing obesity issue in the US. The assumption is that lower fat levels reduce the risk of chronic diseases and improve health. However, research finds that a primary reason for all-cause mortality is poor cardiorespiratory fitness, which means that the heart and lungs are not working together as well as they should. It turns out that the level of cardiovascular fitness in those considered overweight and obese is a far better predictor of mortality.

Some doctors question the sometimes single-minded focus on getting slimmer as a way of becoming healthier and living longer. Among those who are considered obese or overweight, there is little evidence that intentional weight loss lowered mortality rates. Studies suggest that the habit of weight-cycling, constantly losing and regaining weight, increases mortality rates by putting too much stress on the cardiovascular system and metabolic processes.

During the first two decades of the 21st century, the risk for cardiovascular disease increased. Many people assumed a correlation between being overweight and obese and higher levels of blood pressure and cholesterol contributed to this rise in cardiovascular disease. Forty-year trends for overweight and obese American adults ranging in age from 20 to 74 years old, however, showed that rates of hypercholesterolemia and hypertension fell 21 and 18 percentage points, respectively, from 1960 to 2000.

Those who are obese may assume that liposuction is a convenient cure or protection against metabolic diseases such as diabetes. Liposuction decreases subcutaneous abdominal fat, but there is no significant improvement in metabolic disease markers. Studies suggest the real culprit is not subcutaneous but visceral fat, which surrounds the organs. Liposuction does not remove this type of fat. Additionally, research indicates between 10 and 30 percent of people who are obese do not have metabolic problems because they have lower visceral fat levels.