Yale doctor says one good way of lowering risk of cancer is to lose weight

Hartford Courant - 8/3/2022

As rates of obesity rise, aided by the COVID-19 pandemic, the risk of cancer also is increasing, according to Dr. Eric Winer, director of the Yale Cancer Center.

Obesity has increased markedly in the past few years, and has only gotten worse during the pandemic, according to the Centers for Disease Control and Prevention.

In the 20 years before the pandemic began, it rose from 30.5 to 41.9 percent of the population, according to the CDC, and severe obesity increased from 4.7 to 9.2 percent.

A CDC study of more than 400,000 young people ages 2 to 19 from Jan. 1, 2018, to Nov. 30, 2020, showed the rate of increase in body mass index doubled once the pandemic began.

“Excess body weight is associated with more cancers and in two ways,” said Winer, who also is physician-in-chief of Smilow Cancer Hospital. “It both increase the incidence and once you have it, it decreases survival. If you are an overweight person with cancer … your chances of surviving that cancer are somewhat decreased.”

Many cancers are associated with body weight, including breast, endometrial, ovarian, pancreatic, colon and kidney cancers, Winer said.

“I think obesity is going to be our major challenge in terms of preventing cancer,” he said.

The main reason, Winer said, is that obesity increases inflammation in the body, which is a risk factor for cancer.

But, according to another study, don’t expect to lose weight by simply dieting or exercising. A healthy diet must be combined with exercise to lose weight effectively. Rigorous exercise and an unhealthful diet will not do it. The study of 346,627 people in the U.K.Biobank was published in the British Journal of Sports Medicine.

“The study was very clear about this,” Winer said. “You can’t exercise and then eat a bad diet because if you do that’s it’s not going to help. You can’t go exercise and then go eat a Big Mac.”

“They appear to be independent factors,” Winer said. “Whatever is negative about bad eating does not seem to be fixed by exercising.”

You also can’t eat a healthful diet with fewer calories and expect to lose weight if you don’t exercise, the study said. Winer said 30 minutes of moderate exercise five days a week is sufficient. “That seems pretty reasonable,” he said.

“It’s a very large study and it looks like they’re acting independently in decreasing cancer incidence if you eat a good diet and you exercise,” he said.

Winer took up both posts Feb. 1, succeeding Dr. Charles Fuchs, who is now senior vice president and global head of oncology and hematology drug development at Genentech and Roche.

Ed Stannard can be reached at estannard@courant.com, 203-993-8109.