Obesity During Young Adulthood Linked to Pancreatic Cancer Risk

By Hillary Eames
Sunday, September 1, 2019

People with a BMI of 30 or higher have a 20% greater risk of developing pancreatic cancer, according to the American Cancer Society (ACS), and the condition is more common in older adults. But a recent study suggests excess weight in early adulthood may pose more risk than weight gained later in life.

While pancreatic cancer is comparatively rare — roughly 3% of cancers in the U.S. — it is the third most fatal cancer, with fewer than one in 10 patients surviving five years. Moreover, in recent years, pancreatic cancer rates have increased. Some research suggests that is associated with rising obesity rates.

Citing findings presented at the annual meeting of the American Association for Cancer Research, Eric J. Jacobs, PhD, Senior Scientific Director of Epidemiology Research at the ACS, estimates that nearly 30% of all pancreatic cancer deaths among those born between 1970 and 1974 will be linked to excess weight — nearly double the rate of pancreatic cancer deaths associated with excess weight among those born in the 1930s.

“The estimate is based on two things,” Jacobs says. “First, a five-unit increase in BMI was associated with a 25% higher risk of pancreatic cancer. Second, there has been a huge increase in the prevalence of obesity over time in the United States. So, by putting those two things together, we can calculate the proportion of pancreatic cancer deaths in different generations that will be due to excess weight, and what’s driving the difference in those is the increase in obesity.”

Jacobs and his colleagues examined data from 963,317 patients enrolled in Cancer Prevention Study II, a cancer mortality study that followed patients from 1982 to 2014. Approximately 8,400 patients died of pancreatic cancer, and Jacobs found that patients with a higher BMI at an earlier age were more likely to die from the disease.

“While pancreatic cancer strikes older adults, reducing the risk of excess weight in childhood and early adulthood can help prevent that risk.”
— Eric J. Jacobs, PhD, Senior Scientific Director of Epidemiology Research at the American Cancer Society

Obesity, Inflammation and Cancer

Those findings follow on a 2018 study published in Cancer that linked adolescent overweight or obesity with later pancreatic cancer risk. The research involved roughly 1.8 million Israeli Jewish men and women. Over a median follow-up of 23 years, the study reported 551 cases of pancreatic cancer, and obesity was associated with increased cancer risk when compared with the risk to participants of normal weight.

Chanan Meydan, MD, Resident Physician at Mayanei HaYeshua Medical Center, Department of Internal Medicine, in Bnei Brak, Israel, notes the deepening awareness of obesity’s possible association with cancer.

“Ongoing research reveals the activity of inflammatory ‘machinery,’ which includes a wide variety of signaling molecules, in obesity states and other related diseases forming the metabolic syndrome (e.g., diabetes mellitus and hypertension),” Dr. Meydan, who wrote a commentary in Cancer on the 2018 study, states in an email. “In my opinion, this can hypothetically explain the higher occurrence of cancer in obese populations, although this connection is far from established so far.”