Colon cancer cases are soaring in young people, alarming experts and leaving doctors scrambling for answers as to why.

Now, a study published by a team of international researchers in the journal Neoplasia, offers new clues.

The study analyzed “very early-onset colorectal cancers” —defined as a diagnosis before the age of 35 — and found three main risk factors.

A diet deficient in calcium was considered the highest risk factor, linked to approximately one in five deaths from colon cancer in the very young.

Alcohol consumption was determined as the second largest risk factor, while obesity was determined to be the third.

By chance, a recent study found that drinking a single large glass of milk every day may be associated with a reduced chance of developing colon cancer, particularly in women.

For the study, the team used data from the Global Burden of Disease and found that global colon cancer cases in people under 35 years old almost doubled between 1990 and 2019 from 21,874 to 41,545.

In those under 35, the disease also appeared to disproportionately affect men. In 2019, data showed that there were 25,432 cases in men while there were only 16,113 cases among women.

Global deaths also increased during that analyzed time period from 11,445 to 15,486, according to the study, which linked a diet low in milk and calcium, alcohol use and high body mass index as “main contributors to deaths.”

Surprisingly, lack of exercise and smoking reportedly had “less contribution to deaths.”

Experts have also examined environmental triggers, ultra-processed foods or certain diets as causes for colon cancer, which is diagnosed in 107,320 Americans annually.

While it is typically considered a disease that disproportionately affects older populations, colon cancer — which causes rectal bleeding, abdominal pain, changes in stool habits, weight loss, anemia and fatigue — has surged in all age groups.

“It’s been pretty alarming to all of us,” Dr. Coral Olazagasti, an assistant professor of clinical medical oncology at University of Miami Sylvester Comprehensive Cancer Center, previously told The Post.

“In the past, you would think cancer was a disease of the elderly population. But now we’ve been seeing trends in recent years of people getting diagnosed with cancer earlier and earlier.”