Men who eat ready-to-eat foods — particularly those containing meat — have a significantly increased risk of developing colon cancer, a new study finds.
Researchers from Harvard University and Tufts University, both in the Boston, Massachusetts area, found that men who ate the most processed foods had a 30 percent increased risk of developing colon cancer. No association was found in women.
Meals containing meat were found to be the worst for a person’s health, including meals containing sausage, bacon, ham, and fish cakes. High consumption of sugary drinks and sodas also increased a person’s risk of cancer.
Processed food consumption has long been linked to many short- and long-term health problems, although these results may be most troubling for those who frequently opt for quick TV dinners.
Regular consumption of ultra-processed foods can increase a man’s chance of developing colon cancer by almost 30%, although no increased risk has been found in women
Researchers, who published their findings in the BMJ on Wednesday, collected data from over 200,000 participants spanning over 25 years for the study.
Everyone was asked how often they ate each of the 130 foods. Participants were divided into quintiles based on how often they consumed highly processed goods.
Over the 25 years, 1,294 cases of colorectal cancer were detected in the 46,341 men in the study and 1,922 in the 159,907 women.
A colonoscopy every 10 years could save your life from colon cancer
What is a colonoscopy?
A colonoscopy is an exam to look for abnormalities and changes in the large intestine and abdomen.
How is it done?
Patients are either sedated or, in rare cases, given general anesthesia to relieve the pain they are feeling.
A long, flexible tube is inserted into the rectum. A tiny video camera is attached to the tip so the doctor can see the inside of the colon.
If necessary, the doctor can remove polyps or other tissue abnormalities and take tissue samples.
A colonoscopy usually takes about 30 to 60 minutes.
How do I prepare the day before a colonoscopy?
Doctors recommend that patients eat a low-fiber, easily digestible diet three to four days before the colonoscopy.
The day before the procedure, patients are not allowed to eat anything solid and are only allowed to drink clear liquids.
The night before the colonoscopy, patients must take laxatives to keep the digestive tract clear.
When should I have a colonoscopy?
The US Preventive Services Task Force recommends that all adults between the ages of 45 and 75 be screened for colon cancer.
Patients between the ages of 75 and 85 are advised to speak to their doctor about when to have a colonoscopy.
If the colonoscopy does not find any signs of cancer, it should be performed every 10 years.
Why is a colonoscopy important?
Aside from skin cancer, colon cancer is the third most common cancer diagnosed in both men and women in the United States
In 2021, 104,270 new cases of colon cancer and 45,230 new cases of rectal cancer are expected to be diagnosed.
It is the third leading cause of death from cancer in males and females separately and the second leading cause of death from cancer when males and females combined, with an expected 52,980 deaths in 2021.
Sources: Mayo Clinic, American Cancer Society
The enormous sample combined with the long time period allows the researchers to be more confident in their results than would be the case with other cancer studies.
“Cancer takes years or even decades to develop, and from our epidemiological studies we have shown the potential latent effect — it takes years to see an effect of a given exposure on cancer risk,” said Mingyan Song, co-senior -Study author and epidimeologist at Harvard, in a statement.
“Because of this lengthy process, long-term exposure to the data is important to better assess cancer risk.”
In men, they found a clear correlation between people who ate more of the foods and whether they developed the disease.
They particularly highlighted meat-based products, which is what they expected for the study.
“We initially thought that colorectal cancer might be the cancer most affected by diet compared to other types of cancer,” said Dr. Lu Wang, the study’s lead author, in a statement.
“Processed meat, most of which falls into the ultra-processed food category, is a strong risk factor for colon cancer.
“Ultra-processed foods are also high in added sugars and low in fiber, which contribute to weight gain and obesity, and obesity is an established risk factor for colorectal cancer.”
While the risk factors are well known, the powerful impact these foods have on a person’s cancer risk is staggering.
Many Americans regularly eat ultra-processed foods for their convenience. Some are even branded as healthy alternatives that can help a person lose weight and manage other dietary conditions.
As expected, the researchers also found a strong correlation between consumption of sugary drinks and cancer.
However, not all processed foods turned out to be negative. Women who consumed processed dairy actually had a slightly reduced risk of colon cancer.
“We found an inverse association between highly processed dairy products like yogurt and colon cancer risk in women,” said Fang Fang Zhang, co-senior author of the study and a cancer epidemiologist at Harvard, in a statement.
“…Foods like yogurt may potentially counteract the harmful effects of other types of ultra-processed foods in women.”
However, a similar correlation was not found in men in the study.
Whether there are actual gender differences in how the body processes these foods, or whether some other variable researchers are missing, remains to be determined.
“Further research needs to determine whether there is a true sex difference in the associations, or whether the null results in women in this study are just due to chance or other uncontrolled confounders in women that weakened the association,” Song said.