Clinical oncologists and nutritionists have said people consuming white bread as a staple food are at risk of developing colorectal cancer.
Apart from white bread, they said all other forms of bread including burgers made from refined flour were also unhealthy if consumed excessively as they do not contain fibre that aids bowel movement.
According to the World Health Organisation, colorectal cancer is a type of cancer that affects the colon, large intestine or rectum.
The global health body said it is the third most common cancer worldwide, accounting for approximately 10 per cent of all cancer cases and the second leading cause of cancer-related deaths worldwide, adding that it predominantly affects older individuals, with the majority of cases occurring in people aged 50 and above.
Experts, who spoke exclusively with PUNCH Healthwise in different interviews against the backdrop of a recent study that indicated that those consuming refined white bread as a major staple were at risk of developing colorectal cancer.
In a study published on Nutrients, which has elicited comments and reactions from different scholars, the authors found a link between white bread and colorectal cancer.
Nutrients is an international, peer-reviewed, open-access journal of human nutrition published semimonthly online by a medical journal, MDPI.
Themed ‘Diet-Wide Association, Genetic Susceptibility, and Colorectal Cancer Risk: A Prospective Cohort Study,’ Dongqing Jin and his team examined the risk for colorectal cancer related to the intake of certain foods and nutrients.
Analysing data from over 118, 000 participants, researchers found that white bread intake was associated with a higher risk for colorectal cancer. It also shows that consuming higher amounts of fibre and calcium was associated with a decreased risk.
They, however, call for more research to confirm these findings and potentially lead to guidance in clinical practice.
Reacting to the study, a Clinical Oncologist and Chief Clinical Coordinator of NSIA-Lagos University Teaching Hospital Cancer Centre, Dr Habeebu Muhammad, said consuming white bread as well as other food made from refined flour predisposes one to colorectal cancer.
He said, “The study is correct because white bread is a refined food from refined flour and as such, not organic. It predisposes a person who eats them as major food stable to colorectal cancer because they do not have fibre.
“All bread and burgers will do the same because they are low in fibre or do not have fibre at all. Fibre helps the body to empty the bowel by increasing the bulk.
“But white bread and other refined food will stay longer in the body. They produce some nitrate substances that may irritate the walls of the colon and thereby lead to colorectal cancer.
“When these refined foods are taken as staple foods, that is, eating as a regular main source of food, they are predisposed to colorectal cancer. Foods like noodles and fast food generally are not organic and consumers stand the risk of colorectal cancer.
“Without fibre, the movement of the bowel is reduced and the bowels stay longer in the body irritating the body.”
On the solution, he said, those, especially children who are served noodles and other food from refined flour, should have their meals balanced with high fibre content meals.
“So, we need organic food whether children or adults in order not to predispose ourselves to the risk of colorectal cancers,” he quipped.
Corroborating his statement, a Registered Dietician Nutritionist, Olusola Malomo, said it is true that eating excess white bread can predispose one to colorectal cancer.
He explains, “When you eat refined bread over time, the gastric motility of the GIT, that is, from mouth to the anus will be affected. And because dietary fibre in food absorb water, the movement of the bowel is easy.
“But when you eat a lot of refined food, and because it is refined, its capacity to absorb water is reduced, then the level of it sticking together increases thereby reducing the time it moves from the mouth to the anus.
“So, the longer food stays within the system, the more harm would be done within. So, white refined bread stays longer within the large intestine, colon, and rectum.
“Then, you also discover that defecation becomes a herculean task because the flow is not there, the food movement is not good enough and it becomes more difficult for the transition outside. For some people, it will be painful and they will stay longer in the toilet.”
On the way forward, Malomo, who is also a diet therapist, said, “Eating food high in fibre is a way out. If you were to eat your white bread, you could mix it with beans. By this, you are increasing the fibre level of the bread. So, we need to plan our meals and diet, if you are to eat white bread, don’t eat it morning, afternoon, and night. Don’t eat it every day.
“Eating them will not bring the cancer but what will bring the cancer is the long transition the food stays within the small and large intestine even with the level of water that will be absorbed.
“So the way forward is to increase the source of our dietary fibre, either soluble fibre or insoluble fibres. Soluble informs of vegetables, fruits like watermelons, and some cereals.
Insoluble fibre can be found in Irish and sweet potatoes, yams, ofada rice, wheat, plantain, and corn among others. Fibre in flour has been removed in the food processing to increase their shelf life.”
