Ultra-Processed Foods Linked to Colorectal Cancer in Men

Researchers discovered that males who consumed a lot of foods that were highly processed had a higher chance of getting colorectal cancer than men who did not.

Due to simplicity and convenience, many Americans disregard the less-than-ideal nutritional content in pre-cooked and fast meals. Scientists from Tufts University and Harvard University hope that after finding a connection between excessive intake of ultra-processed foods and an elevated risk of colorectal cancer, this will alter for many people.

The study, which was just published in The BMJ, found that men who ate a lot of ultra-processed foods had a 29% higher chance of developing colon cancer than men who ate a lot less of it. The third most common cancer in the US is colorectal cancer. The same link was not discovered by the researchers in women.

A growth inside the colon or rectum known as a polyp frequently marks the beginning of colorectal cancer. In order to avoid colorectal cancer, polyps should be found and removed.

When compared to other cancer types, "we started off thinking that colon cancer could be the cancer most impacted by nutrition," said Lu Wang. She is a postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts and the study's lead author. "The majority of ultra-processed foods, including processed meats, increase the risk of colorectal cancer. Added sugars and a lack of fiber in ultra-processed meals both lead to weight gain and obesity, which is a recognized risk factor for colorectal cancer.                                                              

In the study, responses from over 200,000 participants—159,907 women and 46,341 men—were reviewed from three sizable prospective studies that evaluated nutritional intake and were carried out over a period of more than 25 years. Each participant received a food frequency questionnaire every four years that inquired about their consumption habits for over 130 different items.

Participants' intake of ultra-processed foods was then divided into quintiles for the BMJ study, with values ranging from the least to the most. The highest quintile was discovered to have the greatest risk for colorectal cancer. The study did not identify an overall elevated risk for women who consumed more ultra-processed foods, but there was a definite correlation found for men, especially in cases of colorectal cancer in the distal colon (the last part of the colon).

The results indicated differences between how men and women consume ultra-processed meals and the potential associated cancer risk. The research team identified 1,294 male cases of colorectal cancer among the 206,000 patients who were tracked for more than 25 years and 1,922 female cases.

The strongest link between ultra-processed foods and colon cancer in men was found to be with ready-to-eat items that contain meat, poultry, or fish. Some processed meats including sausages, bacon, ham, and fish cakes are among these goods. This supports our theory, according to Wang.

Colon cancer or other illnesses may be to blame for these and other signs and symptoms. Consult your doctor if you experience any of the following symptoms:

a modification in bowel habits.

Blood in the stool, either very black or brilliant crimson.

narrower than normal stools.

constipation, diarrhea, or a sense that the bowels do not completely empty.

Constant cramping, bloating, fullness, or gas sensations.

Vomiting.

incredibly exhausted.

Loss of weight for unknown reasons.

According to the study's findings, males who consume more sugar-sweetened beverages like soda, fruit-based drinks, and sugary milk-based drinks had a higher chance of developing colorectal cancer.

The team did discover that not all ultra-processed foods are equally risky for colorectal cancer, though. According to co-senior author Fang Fang Zhang, "We identified an inverse connection between ultra-processed dairy items, including yogurt, and colorectal cancer risk among women." She works as a cancer epidemiologist and serves as the temporary chair of the Friedman School's Division of Nutrition Epidemiology and Data Science.

Overall, there was no correlation between eating ultra-processed food and a woman's risk of colorectal cancer. It's probable that women's consumption of ultra-processed meals has a different nutritional profile than men's.

According to Zhang, yogurt may be able to mitigate the negative effects of other ultra-processed food kinds on women.

Mingyang Song is an assistant professor of clinical epidemiology and nutrition at the Harvard T.H. Chan School of Public Health and a co-senior author on the study. "Further research will need to determine whether there is a true sex difference in the relationships, or if null findings in women in this analysis were simply due to chance or some other uncontrolled confounding factors in women that attenuated the association," the author continued.

Although ultra-processed meals are frequently linked to poor diet quality, there may be other factors that influence the risk of getting colorectal cancer in addition to the ultra-processed foods' poor diet quality.

For instance, there are possible effects of dietary additives on the gut microbiota and inflammation, both of which may encourage the growth of cancer. According to Zhang, pollutants that are created during food processing or that have moved from food packaging may also promote the growth of cancer.

The study team had a lot of information to examine and evaluate because each of the three investigations had more than 90% follow-up rates.

According to epidemiological research, "Cancer takes years or even decades to develop, and we have established the potential latency effect—it takes years to notice an effect for particular exposure on cancer risk." Song It's crucial to have long-term exposure to data to better assess cancer risk because of this drawn-out process.                                                                                                               

121,700 licensed female nurses between the ages of 30 and 55 participated in The Nurses' Health Study between 1986 and 2014.

There were 116,429 female nurses in the Nurses' Health Study II (1991–2015) between the ages of 25 and 42.

51,529 male health professionals between the ages of 40 and 75 participated in the Health Professional Follow-up Study (1986–2014).

The researchers were left with prospective data from 159,907 women from both NHS trials and 46,341 men from the Health Professional Follow-up Study after an exclusionary approach to exclude past diagnoses or incomplete questions.

Potential confounding variables such race, number of physical activity hours per week, history of endoscopy, smoking status, total alcohol and calorie intake, aspirin use on a regular basis, and menopausal status were taken into account.

Zhang is aware that since the study participants all worked in the healthcare industry, their propensity to eat healthfully and avoid highly processed foods may have been greater than that of the general population. The statistics might also be distorted because of modifications made to food processing techniques over the previous 20 years.

However, Zhang emphasized, "We are comparing within that demographic those who eat bigger amounts vs lower amounts." Therefore, the comparisons are accurate.

In a recent study, Wang and Zhang found a rise in the intake of ultra-processed foods among children and adolescents in the United States. Both results provide credence to the idea that a wide range of populations may include highly processed foods in their daily diets.

According to Zhang, who is also a member of the Tufts Institute for Global Obesity Research, "Much of the dependence on these meals can come down to variables like food access and convenience." "Foods can help extend their shelf lives by being chemically processed, however many processed foods are less healthful than their raw counterparts. We must educate people about the dangers of regularly consuming unhealthy meals and make it simpler for them to select better alternatives.

Wang thinks that this research study, among others, will help bring about improvements in dietary restrictions and recommendations, even if she is aware that change won't come quickly.

Wang continued, "Long-term reform will require a multi-step approach." Researchers are still investigating how dietary guidelines, recipe and formula adjustments, and regulations relating to nutrition might enhance general health and lessen the burden of cancer. We must keep researching the connection between nutrition and cancer, as well as potential remedies to ameliorate the situation.

Mengxi Du, Kai Wang, Neha Khandpur, Sinara Laurini Rossato, Jean-Philippe Drouin-Chartier, Euridice Martnez Steele, Edward Giovannucci, Mingyang Song, and Fang Fang Zhang. "Association of ultra-processed food consumption with colorectal cancer risk among men and women: results from three prospective US cohort studies." The BMJ, 31 August 2022. DOI: 10.1136                                                                                                                                                          By TUFTS UNIVERSITY