Obesity is when your body has too much fat. Obesity can cause a lot of damage to your body. People with severe obesity are more likely to have other diseases. These include type 2 diabetes, high blood pressure, sleep apnea, and many more. Combined with obesity, these diseases may lead people to have a lower quality of health. In some cases, these can lead to disability or early death.
Obesity is a major cause of type 2 diabetes. People affected by obesity or severe obesity are about 10 times more likely to have type 2 diabetes (1). Type 2 diabetes can nearly double the risk of death (2). Type 2 diabetes can lead to:
- Heart disease
- Kidney disease
- High blood pressure
- Circulatory and nerve defects
- Hard-to-heal infections
- And more
Obesity is a major risk factor for high blood pressure(also known as “hypertension")(3).About 3 out of 4 hypertension cases are related to obesity(4). Hypertension increases the risk of other diseases. These include coronary heart disease (CHD), congestive heart failure (CHF), stroke, and kidney disease.
Heart disease kills about 600,000 people every year in the United States. The American Heart Association considers obesity a major risk factor for heart disease. Large studies show that the risk for heart disease increases with obesity(5). People with severe obesity are at a higher risk for coronary artery disease. This means they have a higher risk of a heart attack.
Obesity increases your risk of heart failure. Severe obesity is associated with irregular heartbeats (arrhythmias). These arrhythmias can triple the risk of cardiac arrest. However, some excess weight can protect against dying from heart failure after the diagnosis is made(6).
People with obesity have reduced lung capacity. These people are at higher risk for respiratory infections. They are more likely to have asthma and other respiratory disorders. Asthma has been shown to be three to four times more common among people with obesity(8).
More than half of those affected by obesity (around 50-60 percent) have obstructive sleep apnea (OSA) In cases of severe obesity, this figure is around 90 percent7). OSA is a very serious breathing disorder. OSA occurs when excess fat in the neck, throat, and tongue block air passageways during sleep. This blockage causes apnea, which means a person stops breathing for a time. A person with OSA may have hundreds of apnea episodes each night. Apnea episodes reduce the amount of oxygen in a person’s blood.
OSA may lead to high blood pressure, pulmonary hypertension, and heart failure. OSA can cause sudden cardiac death and stroke. Because apnea episodes interrupt the normal sleep cycle, you may not reach restful sleep. This can lead to fatigue and drowsiness. If untreated, this drowsiness may raise your risk of motor vehicle accidents.
Cancer affects more than half a million lives per year in the United States alone. Obesity is believed to cause up to 90,000 cancer deaths per year. As body mass index (BMI) increases, so does your risk of cancer and death from cancer. These cancers include:
- Endometrial cancer
- Cervical cancer
- Ovarian cancer
- Postmenopausal breast cancer
- Colorectal cancer
- Esophageal cancer
- Pancreatic cancer
- Gallbladder cancer
- Liver cancer
- Kidney cancer
- Thyroid cancer
- Prostate cancer
- Non-Hodgkin’s lymphoma
- Multiple myeloma
For people with severe obesity, the death rate increases for all types of cancer. The death rate is 52 percent higher for men and 62 percent higher for women(9).
Cerebrovascular Disease and Stroke
Obesity puts a strain on your whole circulatory system. This strain increases your risk for stroke. Obesity can lead to other stroke risk factors. Stroke risk factors include heart disease, metabolic syndrome, hypertension, lipid abnormalities, type 2 diabetes and obstructive sleep apnea(10).
Gastroesophageal Reflux Disease (GERD)
Gastroesophageal Reflux Disease (GERD) causes stomach acid or intestinal secretions to leak into your esophagus. Common GERD symptoms include heartburn, “indigestion”, throwing up food, coughing (especially at night), hoarseness, and belching. Between 10 percent and 20 percent of the general population experience GERD symptoms regularly.
Obesity has been associated with higher risk of GERD, erosive esophagitis and rarely, esophageal cancer (adenocarcinoma)(11).
Bone/Joint Damage and Accidents
Obesity, in particular severe obesity, contributes to a number of bone and joint issues. These issues can increase the risk for accidents and personal injury. Bone and joint issues can include:
- Joint diseases (osteoarthritis, gout)
- Disc herniation
- Spinal disorders
- Back pain
- Pseudotumor cerebri, a condition associated with disorientation, headache, and visual impairment.
- Alzheimer’s Disease: Studies find that obesity during middle-age may contribute to conditions that increase the risk for dementia and Alzheimer’s disease later in life(12).
- Kidney Disease: Hypertension, Type 2 diabetes and congestive heart failure are major contributors to kidney disease and kidney failure. All of these conditions are caused or made worse by obesity.
- Suicide: Studies have shown a correlation between severe obesity and major depressive disorder (12). Physical and social discrimination issues surrounding obesity may contribute to this depression. Studies are mixed on whether obesity is associated with higher suicide rates. However, most studies seem to suggest lower rates of suicide in people with obesity.
- Septicemia: Septicemia is a serious infection that can quickly lead to septic shock and death. Studies have shown that people affected by obesity, particularly severe obesity, are at higher risk of septicemia.
- Liver Disease: Obesity is the major cause for fatty liver and non-alcoholic fatty liver disease. Most people with severe obesity have non-alcoholic fatty liver disease. Fatty liver disease can cause scarring of the liver, resulting in worsened liver function, and this can lead to cirrhosis and liver failure.
- Other conditions that could become life-threatening: maternal gestational diabetes and preeclampsia during pregnancy, increased incidence of miscarriages and stillborns, gallbladder disease, pancreatitis, and more.
- Other conditions resulting in diminished quality of life: stress urinary incontinence (leakage), polycystic ovarian syndrome, infertility, and skin fold rashes.
Obesity can have a dramatic impact on your body. The conditions related to obesity can be detrimental to your health. However, many of these complications can be avoided or cured through weight loss.
- Guh DP, Zhang W, Bansback N, et al. The incidence of co-morbidities related to obesity and overweight: a systematic review and meta-analysis. BMC Public Health. 2009; 9:88
- Mulnier HE, Seaman HE, Raleigh VS, et al. Mortality in people with Type 2 diabetes in the UK. Diabet Med. 2006 May;23(5):516-21
- Wilson, Peter WF, et al. Overweight and obesity as determinants of cardiovascular risk: the Framingham experience. Arch Int Med 2002;162(16): 1867-1872.
- Landsberg, Lewis, et al. "Obesity‐related hypertension: Pathogenesis, cardiovascular risk, and treatment—A position paper of the The Obesity Society and the American Society of Hypertension." Obesity 21.1 (2013): 8-24.
- Jensen, Michael D., et al. 2013 AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults. J Am Coll Cardiol (2013).
- Curtis, Jeptha P., et al. "The obesity paradox: body mass index and outcomes in patients with heart failure." Archives of internal medicine 165.1 (2005): 55-61.
- Drager, Luciano F., et al. "Obstructive sleep apnea: a cardiometabolic risk in obesity and the metabolic syndrome." Journal of the American College of Cardiology 62.7 (2013): 569-576.
- Camargo, Carlos A., et al. "Prospective study of body mass index, weight change, and risk of adult-onset asthma in women." Archives of Internal Medicine 159.21 (1999): 2582-2588.
- Calle, Eugenia E., et al. "Overweight, obesity, and mortality from cancer in a prospectively studied cohort of US adults." New England Journal of Medicine 348.17 (2003): 1625-1638.
- Chen, Hsin-Jen, et al. "Influence of metabolic syndrome and general obesity on the risk of ischemic stroke." Stroke 37.4 (2006): 1060-1064.
- Hampel, Howard, Neena S. Abraham, and Hashem B. El-Serag. "Meta-analysis: obesity and the risk for gastroesophageal reflux disease and its complications." Annals of Internal Medicine 143.3 (2005): 199-211.
- Kivipelto, Miia, et al. "Obesity and vascular risk factors at midlife and the risk of dementia and Alzheimer disease." Archives of neurology 62.10 (2005): 1556-1560.
- Onyike, Chiadi U., et al. "Is obesity associated with major depression? Results from the Third National Health and Nutrition Examination Survey." American journal of epidemiology 158.12 (2003): 1139-1147.