Study: Weight loss surgery lowers cancer risk

A new study has concluded that people who have lost large amounts of weight as a result of bariatric surgery have a greatly reduced risk of developing cancer.

The study followed more than 30,000 obese adults for nearly 10 years and found that those who underwent the weight-loss procedure had a 32 percent lower risk of developing cancer and a 48 percent lower risk of dying from the disease. , compared with a similar group of people without surgery, on average.

People who had weight-loss surgery lost approximately 55 pounds than those who did not during the study, and the researchers found that the greater the weight loss, the lower the risk of cancer.

The new research focuses on weight loss through bariatric surgery, and the study authors hope that the benefit will also be applied to weight loss through other methods, such as diet and exercise. or the use of weight loss medications.

The co-author of the study Dr. Stephen E. Nissen said: “The findings provide an additional reason why obese people lose weight.”

“This is an important public health message, and I think a lot of the public doesn’t understand or realize that obesity is a strong risk factor for cancer, and certainly don’t understand that it can be reversed,” he said. said Dr. Nissen, academic director of the Cleveland Clinic’s Heart, Vascular and Thoracic Institute.

This shows that treating obesity and achieving clinically significant weight reductions can improve patients ’health outcomes, said the expert not involved in the study, Drs. Anja Gastropov of Yale University.

According to the Centers for Disease Control and Prevention, obesity is a leading cause of preventable cancers, along with smoking, excessive alcohol consumption, and UV exposure, and people who are overweight or obese have more likely to have 13 different types of cancer, including endometrial cancer Uterus, breast, kidney, liver, esophagus, colon, and rectum.

Approximately 13 obesity -related cancers make up 40 percent of all cancers diagnosed in the United States each year.

The authors of the study reported that it is not entirely clear why obesity causes cancer, but one possible cause is inflammation.

Studies show that fat cells release a variety of inflammatory proteins known as cytokines into the bloodstream, which have been shown to stimulate cancer cells, and many scientists believe that chronic state of inflammation caused by fat cells is also one of the reasons why people are obese. with a higher rate of cancer A complication of Covid-19.

Dr. said. Nissen: “Fat cells are often thought of as inactive, just sitting there and doing nothing, but in fact, they are metabolically active. Mechanisms by which cancer is caused. ”

According to the Centers for Disease Control and Prevention, obese people tend to have higher levels of hormones such as insulin and insulin-like growth factor-1, or IGF-1, which can stimulate growth. of cancers of the colon, kidney, prostate and endometrium. .

Bariatric surgery can lead to significant weight loss, although some patients eventually return some of the weight they lost. Studies show that most people with bariatric surgery are able to maintain their body weight reduction of more than 20 percent in a decade after their procedure. that’s more than obese people can lose and maintain through diet and exercise alone.

In the study, Drs. Nissen and his colleagues see how the amount of weight loss affects cancer rates. They studied 5,053 obese people who underwent bariatric surgery at the Cleveland Clinic and followed them. Each patient was ‘matched’ to five other patients who were similar in many ways, approximately the same age, gender and ethnicity, had the same medical history and BMI, but had not undergone weight loss surgery.

There were more than 30,000 participants in the study, including 25,265 people in the control group. The average age of both groups was 46, and the average BMI was 45. According to the CDC, a person is considered extremely obese if they are 5 feet tall and weigh approximately 300 pounds.

According to the study, not everyone who suffers from obesity can undergo weight loss surgery if patients must have a body mass index of at least 40, and in the new study, the person who underwent surgery has undergone gastric bypass or gastric sleeve operations. .

A decade later, patients who underwent surgery lost an average of 61 pounds, while those in the control group (who were advised by their doctors to try to lose weight on their own) lost an average of six pounds. Less than 3 percent of operated patients developed cancer, compared with approximately 4.9 percent of those in the nonsurgical group.

“The data suggests that patients need to lose significant amounts of weight, at least 20 to 25 percent of their body weight, to see a beneficial change in cancer risk,” said Ali Aminian, MD, lead author. principal of studies and director of the Institute of Obesity and Metabolism at the Cleveland Clinic. Risk reduction is particularly important for endometrial cancer, which has the strongest association with obesity. ”

Dr. said. Nissen said that while the new study focuses on bariatric surgery, the message is that people should strive to lose weight in any way possible, whether through diet and exercise or with the help of treatment doctors. The United States is undergoing bariatric surgery, says Dr.

doctor’s explanation Gastroov, of Yale University, that since 2013, the American Medical Association has recognized obesity as a chronic disease, emphasizing that, like any other chronic disease, obese people should not feel they need to fight it alone, but they should seek help from a doctor or health care provider who can provide safe and effective treatment.