LEILA FADEL, HOST:
Colorectal cancer is on the rise among people under 50. It's on track to be the deadliest cancer in this age group. Doctors are even seeing cases in people in their 20s and 30s. NPR's Allison Aubrey has been talking to people who've been diagnosed with the disease, and they've been telling her what they wish they had known before their diagnosis. She joins us now. Good morning, Allison.
ALLISON AUBREY, BYLINE: Good morning, Leila.
FADEL: So we tend to think of colorectal cancer as a disease that strikes older people. What are you hearing from these younger adults who have it?
AUBREY: Well, I talked to several people who told me something striking, Leila - that they did not have any symptoms at all before their diagnosis. Shawna Brown - she lives in Stockton, Calif. - was in her late 40s. Her health care provider had mailed her a screening test. You're supposed to take a stool sample, send it back in. But at the time, she just did not think that she was at risk. She felt great. She felt healthy.
SHAWNA BROWN: I didn't have any signs or symptoms, and I wasn't 50 at the time. So I said that doesn't apply to me. So I ignored the test.
AUBREY: This was about the time that the recommended age for screening was lowered from 50 down to 45. And like many people, she was just not aware of this.
FADEL: So how did she find out she had cancer?
AUBREY: Well, during a routine visit, her nurse practitioner really nudged her to do the screening test called a FIT test. She said, look; more younger people are being diagnosed with colorectal cancer. So Shawna Brown did the stool sample. She sent it in, and it came back positive. Then, during a colonoscopy, the doctor found a polyp and evidence of cancer. She was pretty shocked.
BROWN: The moment that I was diagnosed with colorectal cancer scared me out of my mind. But looking back, the purpose of this testing is to catch it early, and I caught it early. Thank God. It saved my life.
AUBREY: She had a surgery to remove a small portion of her colon. That was about two years ago. And she's now cancer free.
FADEL: OK, so from her story, it's clear screening is important. Do scientists know what's behind this rise in cases?
AUBREY: There's a lot of theories about what's behind the rise - everything from a lack of vitamin D to high consumption of processed meat. About 20,000 people in the U.S. under the age of 50 will be diagnosed with colorectal cancer this year, and nearly 3,800 will die. These are estimates from the American Cancer Society. I spoke to T.R. Levin. He's a gastroenterologist at Kaiser Permanente. He says there's a lot of research underway to try to figure out what may be fueling the rise.
T R LEVIN: Some of the drivers are - there's definitely - obesity is more prevalent now than it has ever been. Antibiotics are being used much more frequently and have been - you know, it's kind of a part of childhood. That has the effect of changing the - what's called the microbiome. Sugar-sweetened beverages are much more commonly being used, and there's been at least some early signal that they play a role.
FADEL: OK, so what advice do doctors have about diet?
AUBREY: Well, there's some evidence to show that diet patterns are very important. Studies suggest people who eat a lot of highly processed foods, sugary foods - so cookies, crackers, chips - that can spike insulin. And this pattern of diet is linked to higher rates of cancer and recurrence. Many Americans say they want to eat better, but in our day-to-day lives, it's just so easy to grab and go and fall into unhealthy patterns. So you have probably heard these recommendations before - to eat plenty of fresh food, produce, nuts, seeds, healthy fats and proteins. And the easiest things to cut back on are sugary drinks and snacks.
FADEL: NPR's Allison Aubrey. Thanks, Allison.
AUBREY: Thank you, Leila. Transcript provided by NPR, Copyright NPR.