A new bibliographic review found that 70% of noncommunicable diseases (NCDs) have a documented association with obesity.

This review delved into the epidemiological and physiological relationship between obesity and some of the most common NCDs.

According to the researchers, the goal is to prevent these diseases by reducing the burden of obesity. NCDs as a whole are one of the leading causes of death and disability worldwide.

According to the World Health Organization (WHO), NCDs cause 41 million deaths a year, representing 74% of all deaths worldwide. The high incidence, combined with the high cumulative cost of treatment, generates an enormous financial burden for health systems and global economic development—an estimated $30 billion worldwide from 2011 to 2030.

NCDs are the leading cause of death in Latin America and the Caribbean and will account for approximately 81% of deaths in the region by 2030. The main NCDs are cardiovascular diseases, cancer, diabetes, and chronic respiratory diseases.

The causes of NCDs vary, but they are generally brought on by a combination of genetic predisposition and lifestyle factors known as “obesogenic” condition: dietary and metabolic risk factors plus little physical activity.

Overweight and obesity, which the WHO defines as BMI ≥30, result from an imbalance in energy intake and output.

If the caloric imbalance is chronic, it can cause adipocyte stress, leading to adipose tissue inflammation and fibrosis. If uncontrolled, this local inflammation can spread to other organs and affect the entire body (a process known as “meta‑inflammation”), resulting in harmful systemic consequences, such as insulin resistance and high blood sugar, high triglyceride levels, low LDL levels, and high blood pressure.

A review of the literature on each NCD included in the Global Burden of Disease 2019 study found a positive association with obesity in 71 of 95 disorders (74.7%).

Here is an overview of obesity’s connection to some of the most common NCDs, starting with digestive disorders (The following are excerpts from the study, edited for space and clarity):

Steatotic liver disease and cirrhosis. Metabolic dysfunction‑associated steatotic liver disease (MASLD), previously known as nonalcoholic fatty liver disease (NAFLD), is characterized by excessive fatty buildup in the liver. If left untreated, it can lead to liver failure. Overnutrition is the leading cause of MASLD, and overweight or obesity is one of its five cardiometabolic diagnostic criteria. The prevalence of MASLD in patients with overweight and obesity is around 70‑75%.

Inflammatory bowel disease. The main types of inflammatory bowel disease are ulcerative colitis (UC) and Crohn’s disease (CD). Neither of these diseases has a known cause, and while the typical symptoms (abdominal pain, diarrhea, fever, and weight loss) are similar, they have different etiologies. CD is typically classified as a chronic inflammatory disorder, whereas UC is considered an autoimmune disease. Data from the Nurses' Health Study II prospective study found a significant association between obesity and CD, and other studies have demonstrated more rapid clinical progression in patients who are overweight compared to control groups. The impact of obesity on CD development appears to be greater when obesity begins at an early age.

Pancreatitis. Gallstones are one of the most common risk factors for acute pancreatitis and the leading cause of that disease in 38% of patients. Since obesity (especially abdominal obesity) is a major risk factor for gallstones, it also increases the risk of acute pancreatitis. However, other consequences of obesity are independent risk factors for acute pancreatitis. Hypertriglyceridemia, which is common in obese patients, can cause acute pancreatitis directly, and type 2 diabetes increases the risk of developing that disease. Additionally, obesity has been shown to increase the severity of acute pancreatitis, regardless of its cause.

Diabetes. Type 2 diabetes is the most common comorbidity of obesity. There is a 70‑75% chance that a person with severe obesity will develop type 2 diabetes in their lifetime. Additionally, 80% of patients with diabetes have obesity. The exact mechanisms behind its development are unclear, but evidence suggests a combination of at least three factors: (1) increased insulin resistance due to chronic adipose tissue inflammation and adipokine secretion dysregulation; (2) increased hepatic gluconeogenesis; and (3) pancreatic β cell dysfunction.

Ischemic heart disease and stroke. The Nurses’ Health Study identified obesity as a significant independent risk factor for coronary heart disease in middle‑aged women in the United States. A subsequent meta‑analysis demonstrated similar results in large cohorts of men and women in other regions of the world.

Atherosclerosis. Obesity and atherosclerosis are closely related as they share a main cause: overnutrition. Chronic overnutrition leads to increased concentrations of lipoproteins, which build up into large cholesterol deposits over time.

Colorectal cancer. Colorectal cancer (CRC) is the third most common type of cancer and the second leading cause of cancer death worldwide [33]. A weight gain of 10 kg raises the risk of developing CRC by 8%. Both weight gain in adulthood and obesity in early childhood significantly increase the risk of CRC.

Obesity is the leading cause of NCDs and is associated with NCDs that have serious consequences. It affects a broad spectrum of diseases, including the most common ones, in all populations.

Therefore, the study concludes, obesity must be addressed, and there is an urgent need for pharmacological therapies. New incretin‑based drugs, such as Ozempic, have been wildly successful, achieving effectiveness levels almost comparable to those of bariatric surgery. However, they are considered “forever” drugs, requiring prolonged or indefinite use to maintain the desired effect. This underlines the possible need for continuous treatment, which may raise concerns about long‑term side effects and possible weight regain if the medication is suspended.

That is why the researchers concluded that there is an urgent need for other new approaches with alternative and synergistic treatments.