Not that long ago, obesity was considered a cosmetic condition that only impacted a person’s appearance. Those days are long gone. We now know that obesity affects a person’s health in profound and dangerous ways. That’s why the American Medical Association, the Canadian Medical Association, the World Health Organization, and other prominent organizations classify it as a disease. Obesity even has its own ICD-10 code that physicians and insurance companies use for medical billing.
As it turns out, many Americans have this disease. According to the non-profit organization Trust for America’s Health, obesity rates are now at historic highs with 1 in 3 Americans of all ages being classified as obese. (1)
What is obesity?
The terms overweight and obese are often used interchangeably. Both refer to bodyweight that is more than what is considered healthy for a certain height. (2) Because muscle can cause someone to weigh more on the scale, body mass index (BMI) is used to determine if someone is obese or overweight.
BMI is calculated by dividing the amount someone weighs in pounds by height in inches squared and then multiplying that by 703. For example, a person who weighs 125 pounds and is five feet tall would have a BMI of 24.4, which is in the normal range (125/60/60×703).
Here is the classification for overweight and obesity based on BMI calculation: (3)
- Underweight BMI = < 18.5
- Normal BMI = 18.5 – 24.9
- Overweight BMI = 25.0 – 29.9
- Obese BMI = 30.0 – 39.9
- Morbidly obese BMI = ≥ 40
Based on this classification, morbid obesity, the most dangerous form, is defined as a BMI of 40 or higher. A person who weighs over 200 pounds and is five feet tall would be considered morbidly obese.
Obesity health problems
There are numerous health risks associated with obesity. This is because carrying extra weight can lead to insulin resistance and increased inflammation, both of which are linked to many illnesses including diabetes, cancer, heart disease, and other ill health effects. (4)
Obesity and diabetes
A 2014 study that followed nearly 34,000 young men with an average age of about 31 found that being overweight or obese significantly increased the risk of type 2 diabetes. (5) These men had no other signs or risk factors for diabetes other than the extra weight. Many other studies demonstrate that being overweight increases diabetes risk.
Obesity and cancer
The research regarding the link between obesity and cancer is growing. Obesity is now causally linked to 13 different types of cancer including breast, colon, ovarian, uterine, pancreatic, and several others. (6) Also, research shows that maintaining normal body weight can reduce the risk of many cancers as well.
Obesity and heart disease
When it comes to obesity and heart disease, there’s no debate. Obesity is linked to an increased risk of developing heart disease, specifically heart failure and coronary heart disease. (7) Research shows that obesity alone is a strong independent risk factor. That means that even if there are no other risk factors such as smoking, stress, high cholesterol or high blood pressure, just carrying extra weight can lead to heart disease.
Obesity risk factors
Given the significant health issues associated with obesity, how to prevent it should be a top priority for everyone. Looking at what causes obesity is the first step towards proactive prevention and losing weight if you are presently overweight.
According to the National Heart, Lung, and Blood Institute (NHLBI), there are several known causes of obesity including: (8)
- Energy imbalances when there is more incoming energy in the form of calories and not enough energy going out in the form of physical activity
- Genetic obesity such as Prader-Willi syndrome, Bardet-Biedl syndrome and others
- Endocrine disorders such as hypothyroidism, Cushing’s syndrome, or tumors
- Medications such as antidepressants, antiepileptics, and others
The NHLBI also reports that four key lifestyle factors can increase the risk of obesity:
Overweight individuals should also be aware of obesity hypoventilation syndrome (OHS), where there is excessively slow or shallow breathing throughout the day that is accompanied by obstructive sleep apnea at night in more than 90% of the cases. (9) Proper diagnosis of OHS is important when developing an obesity treatment plan.
How to prevent obesity
Based on the previously mentioned four lifestyle factors, everyone who is interested in preventing obesity or losing weight should focus on:
- Being physically active
- Eating healthy, whole foods, unprocessed diet
- Getting seven to nine hours of sleep each night
- Practicing proactive stress management
The bottom line
Maintaining normal body weight is something everyone should be focused on—our health depends on it! Understanding risk factors and then taking proactive steps to prevent obesity or lose weight will reduce the risk of many illnesses including the top three killers of our time: diabetes, cancer, and heart disease.
- Trust for America’s Health. US Obesity rates reach historic highs—racial, ethnic, gender and geographic disparities continue to persist. Accessed online December 2019.
- National Institutes of Health. Definition & facts for adult overweight & obesity. Accessed online December 2019.
- Purnell JQ. Definitions, classification, and epidemiology of obesity. Endotext. 2018;April 12.
- Redinger RN. The pathophysiology of obesity and its clinical manifestations. Gastroenterology & Hepatology. 2007;3(11):856-863.
- Twig G, Afek A, Derazne E, et al. Diabetes risk among overweight and obese metabolically healthy young adults. Diabetes Care. 2014;37(11):2989-2995.
- Colditz GA, Peterson LL. Obesity and cancer: evidence, impact, and future direction. Clinical Chemistry. 2018;64(1).
- Carbone S, Canada JM, Billingsley HE, et al. Obesity paradox in cardiovascular disease: where do we stand? Vascular Health and Risk Management. 2019;15:89-100.
- National Heart, Lung, and Blood Institute. Overweight and obesity: also known as adiposity. Accessed online December 2019.
- Bacelar de Athayde RA, Bandeira de Oliveira Filho JR, Filho GL, Genta PR. Obesity hypoventilation syndrome: a current review. Journal Brasileiro de Pneumologia. 2018;44(6):510-518.