Cancer and diet

According to the American Cancer Society, more than 60,000 young adults in the U.S. are diagnosed yearly with cancer and of those 9,000 die. Among that age group, cancer is the fourth leading cause of death. Sadly, this number is showing no signs of slowing and may be going up. In fact, while in general cancer rates tend to be higher among those who are older, a recent study published in The Lancet Public Health found there are certain types of cancers presenting more often in younger adults.

The team of researchers conducted a complete examination of the incidence of 30 of the most common cancers — 12 of which were linked to obesity — from 1995 to 2014 in people ages 25 to 84.

“The increases among the young were statistically significant with the fastest increases in ages 24-34,” says study author Hyuna Sung, Ph.D. principal scientist at American Cancer Society. “Among the 12 obesity-related cancers, we found six of them (colorectal, uterine corpus [endometrial], gallbladder, kidney, multiple myeloma, and pancreas) are double the risk in millennials and are about double the risk of baby boomers.”

When researchers evaluated risk for those born in 1950 compared to those who were born in 1985 the numbers were staggering. The incidences of multiple myeloma — rare cancer that attacks the bone marrow— was 59 percent higher, and the risk of pancreatic cancer was double for those born during those aforementioned years.   

So, why the increase?

While an inference could be drawn between the increasing waistline of Americans — 160 million are either overweight or obese — Sung asserts that, while there is convincing evidence that body weight increases the risk of those six cancers, they didn’t formally address the association in the paper.

“Given the causal relationship between obesity and cancer risk, and coinciding trends of obesity with that in cancer rates, we can only speculate the dramatic increase of obesity may have at least partly impacted the cancer rates,” she says. “Additionally, obesity might not be the only thing to blame, because obesity-related behaviors like poor diet and physical inactivity can also be contributing factors.”

But that isn’t the end of the story. Recent statistics from the Centers for Disease Control and Prevention show that about 40 percent of adolescents and 72 percent of adults are overweight or obese. “This implies many young people are projected to carry a longer cumulative exposure to the carcinogenic effect of excess body fat than their parent generations, which may increase their risks of cancers and other chronic diseases in later life.”

Subsequent studies may take a closer look at the association found between obesity rates and the increased risk in cancer in young people. For now, Sung states that absolute occurrences are still lower when compared to those older. “They will be likely lower in the future, but annual increases were faster among the younger than the older.”