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Patient Resources


January 24, 2022

Obesity is a chronic (long-term) medical disease whereby the body carries too much body fat. By 2030, it is projected that 1 in 2 Americans will have obesity (defined as a Body Mass Index, or BMI, of >30 kg/m2). Both overweight (BMI >25 kg/m2) and obesity can make it more likely you will develop other diseases. These problems include, but are not limited to, type 2 diabetes, high blood pressure, stroke, fatty liver and more serious forms of liver disease, sleep apnea, osteoarthritis, gallstones, high cholesterol, gout, and certain types of cancer. Obesity can make many other medical problems harder to treat, lead to increased disability, and even raises the risk of early death. Obesity is sometimes associated with stigma, which can affect a person’s mental health, quality of life, and lead to biases in how people with obesity are treated.  

Endocrine Connection 

Obesity is a very complex metabolic disease and not a problem of willpower or self-control. Having obesity or being overweight is not the patient’s fault, obesity results from a complex biology whereby the body increases the amount of fat it wants to hold on to. As a result, people with obesity may crave more calorie-dense foods and are more likely to store extra calories as fat. The result is weight gain, or more specifically, an increase in the amount of fat the body wants to carry. The reasons for this are not yet well understood but some of the contributors are thought to be unhealthy diet, unhealthy muscle, lack of sleep, disruptions in circadian rhythm, and weight gain-promoting mediations, among others. 

Some medications may cause weight gain, such as those used to treat diabetes, psychiatric illnesses, neurologic disorders, or inflammatory conditions. Your doctor may be able to suggest a different medication that has less effect on weight gain. 

There are some hormone imbalances that can contribute to weight, such as hypothyroidism (under-active thyroid gland) or Cushing’s syndrome (high cortisol levels). These are uncommon causes of obesity. 

Our understanding of obesity is growing rapidly. For instance, we now know that fat cells, the gastrointestinal tract, and the brain produce many hormones that play an important role in how much you eat, how much energy (calories) you spend, and how much you will weigh.  Even the bacteria which live in your intestine can affect your body’s metabolism. Furthermore, not getting enough physical activity, genetic and early-life environmental factors, as well as life events such as illness, pregnancy, or menopause can alter the body’s ability to maintain a lower body weight.   


Research shows that genetics plays an important role in obesity. Some genetic causes of obesity lead to weight gain early in childhood. Some genetic causes of obesity lead to weight gain early in childhood. People with genetic causes of obesity often report high hunger levels, are pre-occupied with food, and may have more than one family member with obesity. Studies show that people with a genetic predisposition to obesity may have greater difficulty losing weight with traditional changes to dietary patterns and regular exercise and may require medications or bariatric surgery to assist in weight management. Medical weight management should be offered to every individual with obesity to provide a custom plan suited for them.  


The environment can also influence one’s risk of developing obesity. Neighborhoods, school systems, workplaces, income, media, education access to health care and availability of healthy foods can all influence health decisions. It is important to create environments that help people engage in physical activity and provide resources that provide them with healthy food options.  

Environmental factors during early life and even before birth can also influence body weight. Research shows that pregnant mothers who smoke, have overweight or obesity, or had type 2 diabetes before or during pregnancy are more likely to have children who have overweight or obesity. Babies who were born prematurely or with low birth weight are also at higher risk.  

Stress and Other Factors 

Stress and a lack of sleep can also lead to obesity. Studies have shown that some people are more likely to overeat when affected by mental health issues such as depression or anxiety. A lack of sleep can disrupt ghrelin (a hunger hormone) and leptin (a hormone that causes one to feel full), increasing the risk for obesity. People who are sleep-deprived may be tired, and less likely to exercise, which leads to fewer calories burned and poor metabolic health. 

The development of obesity or overweight can be helped by the following lifestyle changes: 

  • Reduce intake of foods that are highly processed, rich in sugar or calories, and avoid sugar-sweetened beverages.  
  • Eat whole foods which are dense in nutrients, such as fruit, vegetables, beans, legumes, nuts and seeds, and healthy plant-based fats.  
  • Spend at least 30 minutes a day in moderate physical activity, such as brisk walking. 
  • Learn portions of meals and snacks 
  • Incorporate physical activity in your everyday life, such as taking the stairs whenever possible, parking your car farther out in the parking lot, walking your pet, housework, engaging in gardening, or playtime with your young, loved ones.  
  • Get your household members involved to make changes sustainable. 

Health care providers can diagnose obesity using a number called the body mass index (BMI). Your BMI is calculated from your current height and weight. For most people, the higher their BMI, the more body fat they carry. A person may be considered to have overweight if their BMI is >25 kg/m2 (>23-24 if you are Asian background) and to have obesity if their BMI is >30 kg/m2. For individuals of Asian ethnic background, risks of extra weight are observed at lower levels of body weight, so definitions of overweight (>23-24) and obesity (>27-28) differ in this population.  

Some bodybuilders and athletes have high BMIs, but they have more muscle mass than average and are not considered to have obesity.  Another consideration is where the extra weight is carried on the body; extra weight in the abdominal area carries a higher risk for complications of obesity, such as type 2 diabetes. One easy way to evaluate belly fat is by measuring your waist circumference. Measurement cut-off associated with higher health risks differ from one ethnicity to another. 

Obesity is a complex and chronic disease that often requires a combination of different approaches to manage it. Fortunately, there are effective treatments that combine diet, increases activity, behavioral changes, and in some cases, medications and/or bariatric surgery.  

Nutrition Programs 

Following various nutrition programs such as the Mediterranean or DASH diets can help you lose weight and stay healthy and improve your health but are often challenging to maintain. Advice and support from a dietitian may be able to select a plan which fits your needs the best and helps to meet your weight goals. Choosing a way of healthful eating that you are most able to sustain appears to be the most effective way to maintain healthful eating. 

Increasing Activity and Behavioral Changes 

Participating in moderate physical activity most days of the week together with strengthening exercises is very important in maintaining weight loss and improving overall health. Selecting consistent changes by incorporating movement into daily life, such as walking the dog, can be more sustainable in the lng run. Reducing activities that mainly involve sitting, such as screen time or driving, can also be beneficial. Improving sleep duration can also be beneficial. 

Healthy lifestyle change is important for a comprehensive approach to obesity care but targeting the biology of obesity (with antiobesity medications or bariatric surgery) is critical not only for weight loss but also for weight loss maintenance and comprehensive care of patients with obesity. 

Weight Loss Medications  

Antiobesity medications are a critical tool for patients with obesity. Your doctor may recommend medications for obesity, which include (in alphabetical order): liraglutide, naltrexone-bupropion, orlistat, phentermine, phentermine-topiramate, semaglutide, and setmelanotide. These medications have been approved by the FDA for long- term use and are safe and effective when used with medical supervision. Most of these medications work in the brain, the organ which sets the about of fat your body wants to carry. In order to maintain the weight loss (keep the weight off) you will need to continue to take these medications as you would for any other chronic disease.  

Some people with health problems such as diabetes will need adjustment of medication they take for their diabetes (such as insulin or sulfonylureas) and thus it is important to continue seeing your doctor. Some patients may need a physical exam before they begin physical activity, especially if they have significant heart problems. 

Bariatric Surgery 

Some people with obesity may also benefit from bariatric (weight loss) surgery. Gastric bypass and sleeve gastrectomy are the forms of surgery most used nowadays, and they are both very effective.  

Endocrinologists, who are specialists in hormones and metabolism, can evaluate and treat obesity as well as weight-related diseases, such as type 2 diabetes. They can prescribe anti-obesity medications and care for you throughout your weight journey.
Since it takes time to gain weight, it also takes time to lose weight. Focusing on healthful habits, seeing your doctor consistently, taking the medications as prescribed, can all health you to achieve and maintain your weight and health goals.  

Here are some questions to ask your healthcare provider at your next appointment: 

  • Do I have overweight or obesity and do I need to lose weight?  
  • How much weight loss would improve my overall health? 
  • What physical activity is safe for me? 
  • Are there any hormonal conditions that can be causing the weight gain? 
  • Are there any medications I am taking that can cause weight gain? 
  • What weight loss treatment options are best for me? 
  • What are the risks and benefits of each of these treatment options? 
  • Are anti-obesity medications or bariatric surgery an option for me? 
  • Should I see a registered dietitian? Should I see an endocrinologist? 
  • What can I do to keep the weight off? 
  • What health problems am I at risk for if I do not lose weight? 

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