A study suggests high-fat diets may be to blame for the U.S. colorectal cancer epidemic among young people.
Researchers at the Salk Institute and the University of California, San Diego found that high-fat diets alter gut bacteria and alter digestive molecules called bile acids in mice.
These caused inflammation, increasing the risk of colorectal cancer, a notoriously difficult to treat cancer that is expected to double in young people by 2030.
Although only studied in mice, the study may provide some of the first clues to what caused the spike in colorectal cancer rates in young Americans, which have doubled in the past two decades.
Other factors such as sugar, caesarean section and even a yeast infection are also touted as possible causes.
Evan White is pictured above with his dog Lola and fiancee Katie Briggs. The pair had started dating when Evan had cancer and became engaged when his condition stabilised. However, he died after four years of battling the disease
Marisa Maddox, pictured, was diagnosed with colon cancer at the age of 29. It left her barren and robbed her of the chance to have the big family she always wanted
Dr. Ronald Evans, author of the study and director of the Salk Institute’s Gene Expression Laboratory, said: ‘The balance of microbes in the gut is shaped by diet, and we’re discovering how changes in the gut microbial population (the gut microbiome) can cause problems . that lead to cancer.’
“This paves the way for interventions that reduce cancer risk.”
It’s unclear what specific foods the mice ate or how much fat they contained, but it’s safe to assume they were meant to mimic high-fat foods that are a staple of the American diet, such as fast food.
The study builds on previous research by Dr. Evans, which showed that mice that ate a high-fat diet had higher levels of bile acid.
Bile acids are molecules produced by the liver that help the intestines digest food and absorb cholesterol, fats and nutrients.
The researchers suggested that the shift in bile acids shuts down a key protein in the gut, the Farnesoid X receptor (FXR), increasing the prevalence of colorectal cancer.
In the new study, Dr. Evans and his team found that modified bile acids affected the production of stem cells in the gut. When these are not supplemented often enough, they can cause mutations that promote the growth of cancer cells.
High-fat diets, they said, change the composition of the microbiome and encourage the growth of bacteria that stimulate bile acid production. This creates a vicious cycle of inflammation.
Study author Dr Michael Downes said: ‘We are just beginning to understand these bacterially conjugated bile acids and their role in health and disease.’
“We’ve deconstructed why high-fat diets aren’t good for you, and identified specific strains of microbes that flare up on high-fat diets,” Dr Evans said. “By knowing what the problem is, we have a much better idea of how to prevent and reverse it.”
Data from JAMA Surgery shows colon cancer is expected to increase by 90 percent in people ages 20 to 34
The same data shows that rectal cancer will increase by 124 percent in the youngest age group
The number of cases of colorectal cancer is increasing worldwide, creating an epidemic among young people.
Youth rates are expected to double by 2030, and colorectal cancer is also expected to be the leading cause of cancer deaths in people under 50 by the end of the decade.
This is based on data from JAMA operationThis study found that between 2010 and 2030, colon cancer will increase by 90 percent in people aged 20 to 34. Rectal cancer will have increased by 124 percent in the same age group.
Cancers of the colon and rectum are the third most common type in the US and the third leading cause of death in both men and women.
The American Cancer Society (ACS) estimates that about 153,000 cases of colorectal cancer will be discovered this year, including 19,500 among those under age 50.
About 52,550 people are expected to die from the disease.
Evan White, 24, of Dallas, was one of them. Mr. White had just graduated from the University of Arkansas with a degree in finance when he was diagnosed with colon cancer after ignoring his main symptom – fatigue – for months.
The tumor was not noticed until it had reached stage three, meaning it had spread beyond the colon, making it much more difficult to treat.
He was on his way to marry his girlfriend and move to California, but his dreams were cut short when he died after a four-year battle with the disease.
Mr White’s mother, Dana, told DailyMail.com that her then 24-year-old son’s diagnosis “is just not something you would expect for someone so young.”
A 2020 Colorectal Cancer Alliance study found that many patients with colorectal cancer symptoms were initially misdiagnosed or rejected
Marisa Maddox, a paralegal, survived the disease but was robbed of the chance at the big family she had always hoped for after a colon cancer diagnosis at age 29 left her infertile.
Experts are still working to unravel the cause of this devastating epidemic.
They often blame unhealthy diets, alcohol consumption and a sedentary lifestyle for this shift.
A Cleveland Clinic study suggested that eating red meat and sugar could lead to a higher chance of young people developing colorectal cancer.
However, some studies indicate otherwise.
A 2021 studyFor example, research found that patients with early stage cancer were less likely to become obese or smoke than their older counterparts.
a study published in April examined how being born by cesarean section influenced the likelihood of developing early-onset colorectal cancer. The researchers found that women born by cesarean section were more likely to develop colorectal cancer earlier in life than women who were born vaginally. There was no connection between men.
In addition, antibiotic use has been shown to influence this risk. A study in the journal Gut found that long-term antibiotic use increased the risk of early colorectal cancer. However, it was also associated with a lower risk of rectal cancer.
And one study showed that the fungus Cladosporium sp. was more common in the tumors of young patients than in older subjects.
It is still unclear how Cladosporium sp. could lead to this increase in cases, but the researchers believe it may damage cell DNA. This can turn them into cancer cells.
These environmental factors have a lasting impact on the gut microbiome, which experts believe may increase the risk of colorectal cancer, even if exposure is limited to early life.
Part of what makes colorectal cancer difficult to diagnose is its symptoms, which can often be attributed to other conditions. However, some stand out more than others.
From a study published earlier this year in The New York Times magazine Journal of the National Cancer Institute found that the most commonly reported symptoms were abdominal pain, blood in the stool, diarrhea, and iron deficiency anemia.
In addition, a 2020 study of Colorectal Cancer Alliance68 percent of the participants said they had blood in their stools. The mean age of the participants was 42 years.
The same study also found that many patients with colorectal cancer symptoms were initially misdiagnosed or rejected.
Going undiagnosed for extended periods of time can cause colorectal cancer to progress to a later stage, making it more difficult to treat.
Amid concerns about the rising rate among younger adults, the U.S. Preventive Services Taskforce lowered the screening age from 50 to 45 in 2021.
This is usually a colonoscopy, where a camera is inserted into a person’s rectum, looking for growths or changes in the intestines