Healthcare provider explaining to patient what causes obesity in America

What Causes Obesity in America?

Written on July 17, 2023 by Sendra Yang, PharmD, MBA. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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You may be one of the many Americans who struggle with being obese. Obesity is a prevalent, serious, and expensive condition.[1] In 2013, the American Medical Association (AMA) officially acknowledged obesity as a disease.[2] The AMA noted that recognizing obesity as a disease allows for more attention, improved treatment, and promotes insurance coverage for the condition.

The Centers for Disease Control and Prevention (CDC) defines obesity as a body mass index (BMI) of 30 or higher.[3] A high BMI indicates a high body fat composition. Obesity is mainly thought to be preventable, although there are various factors that influence the development of the disease.[2,4] Continue reading to learn more about obesity, the causes of obesity in America, and prevention strategies.

Obesity Prevalence Continues to Rise

Obesity is considered an epidemic in the United States, and the prevalence of the disease continues to rise.[4,5] The prevalence of obesity increased from 15% in 1976-1980 to 23% in 1988-1994 to 31% in 1999-2000 in American adults between the ages of 20-70.[5] In 2017-2020, the obesity prevalence rose to 42%.[1] Severe obesity increased from around 5% to 9% during the same 2017-2020 time period.

Obesity Is Costly and Has Multiple Comorbidities

Obesity has a significant impact on the nation’s economy and overall health. In the U.S., the estimated yearly medical cost of obesity was approximately $173 billion in 2019.[1] Obese adults have about $1,800 more in medical expenses than people with a healthy weight. Additionally, obesity is related to health conditions that can lead to early death, such as heart disease, stroke, type 2 diabetes, and even certain types of cancer.

What Causes Obesity in America?

Obesity occurs when your weight is higher than what is considered normal for your height based on your BMI.[6] There are several factors that contribute to weight gain and obesity.[6,7] What causes obesity in America? The causes and contributing factors of obesity are highly complex and include[2,4,6-8]:

  • Diet and physical activity: The most frequent cause of weight gain and obesity is extra calories in dietary intake combined with inactivity. Many Americans also choose a diet commonly composed of inexpensive, highly processed foods with increased sugar intake.
  • Environmental influences or social determinants: Social determinants of health (SDOH) are the conditions where we all live, work, learn, and play. Some communities have limited access to parks, sidewalks, and affordable gyms, making it hard for people to be physically active. Additionally, some people do not have access to supermarkets that sell affordable fresh fruits and vegetables.
  • Genetics: Genes may also contribute to your sensitivity to gain weight. The likelihood of your genes impacting obesity can be influenced by external factors such as access to food supply and limited physical activity.
  • Health conditions: Certain medical conditions, such as underactive thyroid and Cushing syndrome, can alter body hormones leading to overweight and obesity.
  • Medications: Several commonly prescribed medications are associated with weight gain. Examples are diabetic drugs, steroids, antihistamines, and birth control medications.
  • Poor sleep: Fewer hours of sleep is correlated with higher BMI, and not getting adequate sleep has been shown to increase hunger and appetite.
  • Stress and emotional factors: Some people, when upset, angry, or stressed, tend to eat more and often select more high-calorie foods.
  • Gut flora: Your microbiome or gut flora can also affect your eating and contribute to difficulty losing weight, leading to weight gain. The gut flora is further involved in your immune function and metabolic processes, playing a role in obesity and other inflammatory diseases.

Everlywell Weight Loss Support

Ways to Prevent Obesity

Understanding the causes of obesity can help you with obesity prevention. Here are some tips on preventing weight gain [9-12]:

  • Eat a healthy diet that includes a lot of fruits and vegetables, and limit salts and sugars in your foods. Choose foods with higher fiber content and less processed foods.
  • Increase physical activity by exercising more and having a routine. Consider going for hikes or brisk walks.
  • Get adequate amounts of quality sleep to help regulate your hormone levels and manage your weight.
  • Manage your stress in healthy ways. Focus on positive changes and beneficial activities.

Weight Management with Everlywell

Everlywell offers a comprehensive online weight loss option via telehealth. The weight management program gives access to GLP-1 prescriptions if you qualify, regular one-to-one virtual visits with a licensed clinician, quarterly at-home lab tests or supplements, and lifestyle content and support for health conditions. Partner with a certified healthcare provider to discuss your weight loss goals through the program.

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  1. Adult obesity facts. Centers for Disease Control and Prevention. Last reviewed May 17, 2022. Accessed July 13, 2023.
  2. Meldrum DR, Morris MA, Gambone JC. Obesity pandemic: causes, consequences, and solutions-but do we have the will? Fertil Steril. 2017 Apr;107(4):833-839. doi: 10.1016/j.fertnstert.2017.02.104
  3. Defining adult overweight & obesity. Centers for Disease Control and Prevention. Last reviewed June 3, 2022. Accessed July 13, 2023.
  4. Wright SM, Aronne LJ. Causes of obesity. Abdom Imaging. 2012 Oct;37(5):730-2. doi: 10.1007/s00261-012-9862-x
  5. Temple NJ. The Origins of the Obesity Epidemic in the USA-Lessons for Today. Nutrients. 2022 Oct 12;14(20):4253. doi: 10.3390/nu14204253
  6. Causes of obesity. Centers for Disease Control and Prevention. Last reviewed March 21, 2022. Accessed July 13, 2023.
  7. What causes obesity & overweight? Eunice Kennedy Shriver National Institute of Child Health and Human Development. Accessed July 13, 2023.
  8. Obesity. Mayo Clinic. September 2, 2021. Accessed July 13, 2023.
  9. Prevention. National Heart Lung and Blood Institute. Accessed July 13, 2023.
  10. Healthy weight, nutrition, and physical activity. Centers for Disease Control and Prevention. Last reviewed June 9, 2023. Accessed July 13, 2023.
  11. Losing weight. Centers for Disease Control and Prevention. Last reviewed June 15, 2023. Accessed July 13, 2023.
  12. Balancing food and activity for healthy weight. Centers for Disease Control and Prevention. Last reviewed June 28, 2023. Accessed July 13, 2023.
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