What is obesity?

Obesity is a serious chronic disease associated with having excess body fat to the extent that it may have a negative effect on your health. Obesity is complex because it is influenced by a combination of many factors both inside and outside your body1,2.

Watch a short animation video outlining the complexity of obesity as a chronic disease.

Factors influencing obesity

The rise of larger meal portions, physical inactivity   due to excessive screen time and easy access to   unhealthy foods are just some of the many   environmental factors that can contribute to you    developing obesity3.
Where you live and your income also influence your risk of developing obesity4. For instance, if you have a high socioeconomic status you are more likely to have obesity if you live in a lower income country, but less likely if you live in a higher income country5.


Obesity is generally understood to develop because of an imbalance between energy consumed as food and the way the body uses this energy for things like physical activity. Any energy the body does not use is then stored as fat6. But this process is complex: appetite and energy expenditure are regulated by the brain based on signals from many parts of the body, including the gut, pancreas and fat-storing tissues7. Additionally, other biologic factors, including certain medical conditions, can have a negative influence on this process.

4  Emotional
Stress, trauma, and mental health problems can sometimes lead to overeating, which may contribute to the development of obesity8,9.

Some people can also be genetically predisposed to obesity, so your family history and ethnicity can also affect your risk of developing the disease10.

The science behind obesity

The science behind obesity is complex, and the underlying cause of the disease – an energy imbalance between food consumed and the energy used – is just one part of the story.

Scroll through this interactive infographic to learn more about the internal and external factors that can influence your chances of developing obesity.

Explore the science


Measuring obesity

Obesity is classified as having a Body Mass Index (BMI) of 30 or higher. BMI – or your weight in kilograms divided by the square of your height in metres11 – may be used by your healthcare professional to see if you are the right weight for your height, and can be a useful tool for identifying obesity. Many people affected by obesity are not even aware that they are living with it.

How can obesity affect your health?

Having obesity can make you more likely to develop other serious diseases that often lead to a decreased quality of health and life.



Possible graphic from the site

Cancer: Cancer is a disease involving the uncontrolled growth of abnormal cells in the body.    These cells prevent the normal function of vital organs and damage essential bodily systems.

Diabetes: Diabetes is a life-long disease marked by high blood sugar levels. It can be caused by too little insulin (the hormone that regulates blood sugar), resistance to insulin, or both. Men and women with obesity are nearly 7 times and 12 times more likely, respectively, to develop type 2 diabetes than people without obesity12.

Gallbladder Disease: Gallbladder disease includes inflammation, infection, stones, or obstruction of the    gallbladder. Men and women with obesity are around 1.5 and 2 times more likely, respectively, to develop gallbladder disease than people without obesity.

Heartburn: Heartburn is a painful burning sensation in the chest, just below the breastbone. The pain often starts in the chest and may move to the neck or throat.

Heart Disease: Heart disease refers to any disorder that affects the heart’s ability to function normally. The most common cause of heart disease is the narrowing or blockage of the coronary arteries that supply blood to the heart.

Lipid disorders: Lipids are fats or fat-like molecules that play many important roles in your body, and include cholesterol and triglycerides. However, having an excess of these fatty substances in your blood can increase your risk of arteriosclerosis and heart disease.

High Blood Pressure: Blood pressure is the force of blood pushing against your artery walls. It is measured in millimetres of mercury (mm Hg). You have high blood pressure - also known as hypertension - if your blood pressure frequently goes above 140/90 mm Hg.

Osteoarthritis: Osteoarthritis is a chronic disease in which joint cartilage – the protective covering on the end of your bones – wears away. Men and women with obesity are 4 and 2 times more likely, respectively, to develop osteoarthritis than people without obesity12.

Clinical depression: Clinical depression is a mood disorder where feelings of sadness, loss, anger, or frustration interfere with your life for an extended time. People with obesity are 55% more likely to develop depression, meanwhile people with depression have a 58% increased risk of developing obesity13.

Sleep Apnea:
Sleep apnoea (also apnea) is a disorder in which you repeatedly stop breathing while you sleep. Studies show that as many as 45% of people with obesity also have sleep apnoea14.

Stroke: A stroke occurs when a blood vessel (artery) that supplies blood to the brain bursts or is blocked by a blood clot.


A new blog about living with obesity

Obesity perspectives is a blog where members of Novo Nordisk's Disease Experience Expert Panels (DEEPs) share their personal perspectives on living with obesity. From starting conversations with healthcare professionals, to starting a movement to advocate change, our bloggers offer thought-provoking opinions, advice and encouragement for every step of the obesity journey.


Follow the conversation


Guided by the people who know best

At Novo Nordisk, we consider people living with serious chronic diseases to be experts. That's why we invite them to become members of our Disease Experience Expert Panels (DEEPs). DEEP members are able to provide disease-specific insights and advice based on real-world experiences. This input guides us as we work to develop better treatments and meaningful support for people living with chronic diseases worldwide.

Explore DEEP

Treating obesity

Obesity is a serious chronic disease that requires treatment. Lifestyle therapies including diet and exercise are important, but are not always enough to maintain weight loss. For some people, medical treatment options, such as medicines or bariatric surgery, may also be considered.




Learn about obesity treatments

Living with obesity

People with obesity encounter challenges on many levels, from finding clothes that fit, to low self-esteem, to frustrating attempts to lose weight. Many also face stigma and weight bias on a daily basis, which can make it even harder to them to succeed. Understanding how these challenges are interrelated is an essential first step to ensuring that people living with obesity get the support they need to achieve better health and a better quality of life.


Living with obesity

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