Cancer has most typically affected people over 50, but a new study from Brigham and Women’s Hospital shows an “alarming” rise in cancer rates in people under 50. The study found that since 1990, younger people have become more likely to develop cancer in the breast, colon, esophagus, kidney, liver, and pancreas, as well as eight other organs.

Adding to the alarm is that early-onset cancers tend to be more aggressive and harder to catch. Medical guidelines for cancer screening generally begin at older ages, after a younger person would have reached the age to catch cancer early, explains Dr. Jayne Morgan MD. And younger people are more likely to shrug off symptoms, she adds.

So, why on earth are these rates climbing? While no one knows for sure, the rise in rates corresponds to global changes in diet, lifestyle, obesity, environment, and the microbiome. Of note, 8 of the 14 early-onset cancers in this study are related to the digestive system. If you also consider past research linking tumor development to an altered microbiome, it seems likely that gut health is a big factor here. This means the same old recommendations apply: get regular exercise, eat diverse and plant-based foods, sit less, cut back on alcohol, and get more sleep.

It also needs to be said that systemic inequities pose major obstacles to the suggestions above. Living in a food desert, not having a sufficient income, and not having access to health information in the first place can make it immensely challenging to make healthy choices. We may all have some degree of choice but governments hold the key to helping all people access the things that make up a healthy lifestyle.

New research shows that more and more people under 50 are getting cancer. Experts believe global changes in diet, lifestyle, obesity, environment, and the microbiome play a key role. Because 8 of the 14 identified cancers relate to the digestive system, experts believe the gut microbiome is key to understanding the rise. More needs to be done at a systemic level to help people access healthy lifestyles.