Does Bariatric Surgery Reduce The Risk Of Cancer?

Bariatric surgery has emerged as a transformative approach to managing obesity and associated health conditions. Its profound impact on weight loss and metabolic improvements has been extensively studied and recognized. In recent years, researchers have started exploring the potential link between bariatric surgery and cancer risk reduction. Obesity plays as a risk factor for several types of cancer, including colorectal, endometrial, breast, and oesophageal cancer. The chronic inflammation, insulin resistance, and altered hormone levels associated with obesity create an environment conducive to cancer development. However, there is growing evidence that bariatric surgery’s effects extend beyond weight loss, and metabolic changes can possibly reduce the risk of certain obesity-related cancers.

How are Obesity and Cancer Connected? Does Undergoing Weight Loss Surgery Help?

Obesity and cancer are closely connected. Numerous studies have proved that obesity is associated with an enhanced risk of developing certain types of cancer. The exact mechanisms underlying this association are complex and not fully understood, but several factors contribute to the connection between obesity and cancer:

Chronic Inflammation

Obesity leads to a state of chronic low-grade inflammation in the body. Inflammation lead to the growth of cancer cells and contribute to tumor development.

Insulin Resistance

Obesity often leads to insulin resistance, where the body’s cells become less responsive to insulin. Insulin regulates the blood sugar levels but also has growth-promoting effects. Elevated insulin levels in the bloodstream can promote cancer cell growth.

Hormonal Imbalance

Obesity can disrupt the balance of hormones in the body, including oestrogen, testosterone, and insulin-like growth factor-1 (IGF-1). These hormones can influence cancer cell growth and proliferation.

Adipose Tissue (Fat) Factors

Adipose tissue produces various bioactive molecules, known as adipokines, which can affect cancer cell behavior and contribute to tumor growth.

Changes in Gut Microbiota

Obesity can alter the composition of gut microbiota, leading to changes in metabolism and inflammation, which may influence cancer risk.

However, the good news is that weight loss achieved through weight loss surgery has been associated with a reduced risk of certain obesity-related cancers. Several studies have shown a decreased risk of cancers including endometrial cancer, colorectal cancer and breast cancer in individuals who have undergone bariatric surgery. While the exact reasons for this risk reduction are not entirely clear but factors like improved insulin sensitivity, reduced inflammation, and hormonal changes play an important role.

It’s important to note that while bariatric surgery may reduce the risk of certain cancers, results may vary from individual to individual. Following a healthy lifestyle, including regular physical activity and a balanced diet, is crucial for overall cancer risk reduction, especially for individuals with obesity or those who have been through the weight loss surgery. It is essential to consult with healthcare professionals for personalized advice and cancer prevention strategies.

Studies and Researches that Support Bariatric Surgery Reduces the Risk of Cancer

Recent studies have shown that bariatric surgery may be associated with a decreased risk of certain obesity-related cancers.

A systematic review and meta-analysis from 2023 shows that bariatric surgery was linked with a significantly reduced overall cancer risk in individuals with obesity. Specifically, there was a significant decrease in the incidence of obesity-related cancers, including breast, colorectal, endometrial, and oesophageal cancer, among those who underwent bariatric surgery. The meta-analysis included a total of studies based on data from 2007 to 2023.


During the 2022 annual meeting of the American Society for Metabolic and Bariatric Surgery (ASMBS), a case study revealed that weight-loss surgery reduces the risk of cancer development compared to obese individuals who have not undergone such procedures. The study analyzed over 1,600 obese individuals who had gastric bypass or sleeve gastrectomy surgery and compared them to a group of 2,100 obese individuals without surgery. Results showed a significantly lower breast cancer risk (1.4%) in the bariatric surgery group compared to those without surgery (2.7%) over a 10-year period.

Likewise, the incidence of different cancer types is decreased:

Lung cancer (0.20% vs. 0.60%)

Gynecologic cancer (0.4% vs. 2.6%)

Brain cancer (0.20% vs. 0.90%)

Kidney cancer (0.10% vs. 0.80%)

Thyroid cancer (0.10% vs. 0.70%)

The study reported that only 5.2% of individuals who underwent bariatric surgery developed some form of cancer, compared to 12.2% of those who did not have the surgery. Additionally, the survival rate after ten years was significantly higher in the surgical group (92.9%) compared to the non-surgical group (78.9%). Similar findings from other studies reinforce the benefits of bariatric surgery in reducing cancer risk and improving overall health. Patients experience a longer and healthier life post-surgery due to lower incidences of health issues like cardiac events and cancers.