What is Obesity?

Obesity is a weight that is higher than what is considered a healthy weight for a given height. Overweight and obesity can result from an energy imbalance or excess fat in the body. The body needs a certain amount of energy (calories) from food to keep up basic life functions. Consuming more calories than are burned will lead to fat storage and thus weight gain and obesity. Obesity is a chronic condition that needs to be addressed by a physician and registered dietitian.

Body Mass Index or BMI is a person’s weight in kilograms divided by the square of height in meters. A high BMI can be an indicator of high body fatness.

  • If your BMI is less than 18.5, it falls within the underweight range.
  • If your BMI is 18.5 to <25, it falls within the normal.
  • If your BMI is 25.0 to <30, it falls within the overweight range.
  • If your BMI is 30.0 or higher, it falls within the obese range.

Obesity is frequently subdivided into categories:

  • Class 1: BMI of 30 to <35
  • Class 2: BMI of 35 to <40
  • Class 3: BMI of 40 or higher. Class 3 obesity is sometimes categorized as “extreme” or “severe” obesity.

Contributing Factors

Obesity results from a combination of causes and contributing factors, which can include behavior and genetics. Some people are simply at risk based on genetics. Food consumption patterns and behaviors also have a lot to do with weight due to quality, quantity, and frequency of food intake. The food environment can play a large role in food choices such as foods available and those that are advertised. The amount and frequency of physical activity can play a large role in weight gain, such as being inactive or sitting for long periods of time. The environment affects an individual’s activity, as well. Certain medications also can play a role in weight gain.

Prevention Methods

Having nutritious food available and affordable in food retail and foodservice settings allows people to make healthier food choices. A healthy diet pattern follows the dietary guidelines for Americans and emphasizes whole grains, fruits, vegetables, lean proteins, low-fat or fat-free dairy products, and drinking plenty of water. When healthy foods are not available, people may settle for foods that are higher in calories and lower in nutritional value. Thus, creating and supporting healthy food environments is an important part of public health work. Having a healthy diet pattern and regular physical activity are also very important for long term benefits and also helps to prevent diseases such as type 2 diabetes or heart disease.

There is no single or simple solution to help the obesity epidemic. It is a very complex problem and requires many different approaches. Everyone must work together, including state and local organizations, business and community leaders, schools, healthcare professionals, and many others. There are many different strategies that can contribute to healthy food environments. These include 1) providing incentives for supermarkets or farmers’ markets to establish their businesses in underserved areas; 2) having nutrition information and caloric content on restaurant and fast food menus; and 3) applying nutrition standards in child care facilities, schools, hospitals, and worksites.

Schools and hospitals can encourage healthier choices by choosing foods that meet dietary recommendations.

Weight Management: Weight is a balancing act where calories play a large part in the equation. Weight loss is achieved by burning more calories than you take in. This can be done by reducing extra calories from food and beverages, as with a diet, or by increasing calories burned through physical activity

Credit: Roper St Francis

Credit: Roper St Francis

Diet: When thinking about weight loss or maintenance, there are many healthy diet plans available. You need to make sure you chose a diet plan that fits your needs and lifestyle. Make sure it consists of various foods from all major food groups, includes things you enjoy eating and can easily find the foods at your local grocery store, fits your lifestyle and budget, includes proper amounts of nutrients to lose weight safely and effectively, and regular physical activity included with the plan. Go to for help on how to create a healthy and balanced diet.

Diet & Exercise: The key to successful weight loss is developing a healthy diet and exercise plan. Diet means eating a well-balanced diet and having lower calorie meals, and exercise means being more physically active. Many people tend to focus on diet when trying to lose weight, but being active is also an essential component of any weight loss program. When active, your body uses energy (calories) to work, helping burn calories you take in from eating.

Physical activity can be simple. Making the bed, shopping, mowing, and gardening are all forms of physical activity. Exercise is a structured and repetitive form of physical activity that you can do on a regular basis.

It is recommended to aim for at least 150 minutes a week of moderate physical activity or 75 minutes per week of vigorous aerobic activity spread throughout the week. An easy way to incorporate more physical activity is to do 30 minutes at least 5 days a week. Walking 10 minutes in the morning, at lunch, and after dinner is a good way to get the recommended 30 minutes in.

Additional Resources

The best additional resource is to consult your primary care physician. For additional online reading, refer to


  1. “Overweight and Obesity Statistics.” U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 19 Sept. 2016.
  2. Staff, By Mayo Clinic. “Weight Loss.” Weight-loss Basics. N.p., n.d. Web. 19 Sept. 2016.
  3. “Healthy Food Environments.” Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 22 Oct. 2015. Web. 19 Sept. 2016.
  4. Roper St Francis. “Obesity and Diseases.” Roper St Francis Health Hub. N.p., 20 Aug. 2014. Web. 19 Sept. 2016.

Originally published 10/16

If this document didn’t answer your questions, please contact HGIC at or 1-888-656-9988.

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