Public health advances over the past decade have pushed down the rates of many cancers, particularly those—like lung cancer—caused by substances we now know are dangerous. On average, cancer deaths are trending downward. However, the rates of certain types of cancers linked to obesity, like colorectal and kidney cancer, are rising in young adults. People who are younger, reports a study published in The Lancet this week, have an increasing risk of developing these diseases.
The results of the study weren’t necessarily surprising, says Karen Basen-Engquist, director of the Center for Energy Balance in Cancer Prevention and Survivorship at the University of Texas MD Anderson Cancer Center. “We know that there are cancers that are linked to obesity; we know that obesity rates have been increasing. In some ways, we’ve been waiting for data to show that.” But the data, she says, were still striking. “Cancer is pretty rare in young people. When we see cancer rates rising in young people, it’s time to get worried.”
Research reliably shows the relationship between obesity and these types of cancers, Basen-Engquist says. For individuals, the strength of the link isn’t as strong as the one between smoking and cancer, for example—smoking is more likely to lead to cancer than obesity—but right now, she says, public health experts are more concerned about the population-level effect of obesity, because it affects more people.
Although it can reduce the risk of cancer (and other related health issues), losing weight and keeping it off is incredibly difficult. Barring that, though, people at risk for these types of cancers might be able to take other steps to stay healthier and reduce their cancer risk:
Cancer risk tends to go up in lockstep with body mass index, Basen-Engquist says, so keeping weight from creeping up might be a good way to keep chances of developing cancer from going up.
It’s much easier, she says, to not gain wait than it is to gain weight and then try to lose it.
On average, American adults gain around one to two pounds per year. “If you spend your 20s doing that, by the time you’re 30, you’re 10 to 20 pounds heavier,” Basen-Engquist says. “It’s important for people to think about preventing weight gain no matter what they’re at.”
Eat well and exercise
One way to keep from gaining more weight is to get regular exercise, and eat a healthy diet, Basen-Engquist says. Although they might not lead to weight loss, both can still help reduce cancer risk: Exercise, for one, can independently help prevent cancer. Inactivity alone, she says, regardless of weight, is a risk factor for cancer. “Exercise can be a factor that protects against cancer, and also prevents weight gain.”
In addition, a diet high in fiber and vegetables, and low in red meat, is associated with a lower overall risk of cancer, she says.
Eating that sort of diet is easier said than done, especially in places with limited access to (often more expensive) healthy foods. In those situations, it’s important to find the factors that are controllable, Basen-Engquist says. “Sugar sweetened beverages are one big issue.”
For people struggling with weight or obesity, cancer isn’t the only elevated health risk, Basen-Engquist says. But this research provides another point for doctors to discuss with patients. “Having this data about cancer provides an additional motivation and conversation topic,” she says.
Those conversations, she notes, shouldn’t just be about weight loss, and should include the behaviors that can help manage weight. “No one can just turn down dial on their weight. It’s important for providers to talk about exercise, diet, portion control.” They should also be thoughtful, and consider using language that makes patients feel comfortable. “People should be making sure they’re talking to patient in a way you’d liked to be talked to,” she says.