A daily green banana may help prevent cancer, according to research, but only if the fruit is green.
Scientists fed participants with a high inherited cancer risk a diet rich in resistant starch, which is plentiful in unripe fruit.
The diet lowered the risk of several kinds of the disease by more than fifty percent, according to the findings.
In addition to oats, cereals, and beans, resistant starch is a common carbohydrate present in oats, cereals, and beans.
Nearly 1,000 patients with Lynch syndrome, a genetic disorder that predisposes individuals to a variety of malignancies, were analyzed in the study, which was headed by British researchers.
Approximately 200,000 Britons are believed to have the hereditary disease, yet less than 5% are aware that they are carriers.
For an average of two years, all patients received a daily dose of resistant starch equivalent to one unripe banana.
Experts determined that while the dose did not cut the risk of colon cancer, it did reduce the risk of cancer in other regions of the body by up to 60%.
This protective effect was especially robust for difficult-to-detect tumors of the upper gastrointestinal system, including oesophageal, gastric, biliary tract, pancreatic, and duodenal cancers.
Protection was shown to persist for 10 years after patients stopped taking the supplement, and researchers believe the findings could be advantageous not only to those with Lynch syndrome but to the general population as well.
Experts from the universities of Newcastle and Leeds conducted the research, which was published in the journal Cancer Prevention Research.
Between 1999 and 2005, roughly one thousand volunteers began taking powdered resistant starch or a placebo daily for two years.
After the treatment phase, there was no significant difference between individuals who took resistant starch and those who did not.
Nonetheless, the research team anticipated a longer-lasting effect and designed the trial to allow for more follow-up.
During the follow-up period, there were only five new occurrences of upper gastrointestinal cancer among the 463 people who had taken the resistant starch, compared to 21 cases among the 455 participants who had taken the placebo.
Professor John Mathers, an expert in human nutrition at the University of Newcastle, stated, “We discovered that resistant starch decreases a variety of malignancies by over 60%.”
The effect was more pronounced in the upper portion of the intestine.
This is significant because malignancies of the upper gastrointestinal tract are difficult to identify and are sometimes not detected in their earliest stages.
The amount of resistant starch utilized in the study was roughly similar to that of unripe banana, he added.
He stated, “Resistant starch can be taken as a powder supplement and is naturally found in peas, beans, oats, and other starchy meals.”
Before they become too ripe and soft, the starch in bananas resists decomposition and travels to the colon, where it can alter the type of bacteria that reside there.
According to Professor Mathers, researchers assume that resistant starch, which is not digested in the small intestine but ferments in the large intestine, nourishes good gut flora, hence modifying the production of bile acids.
He stated, “We believe that resistant starch may minimize the development of cancer by altering the bacterial metabolism of bile acids and lowering the sorts of bile acids that might damage human DNA and ultimately cause cancer.”
However, additional research is required.
Professor Tim Bishop, a genetics expert at the University of Leeds who was also engaged in the study, stated that the findings were intriguing but that additional research was required.
‘The results are intriguing, but the size of the protective impact in the upper gastrointestinal system was unexpected,’ he added. ‘Therefore, additional study is necessary to reproduce these findings.’
Lynch syndrome is a hereditary disorder that reduces the likelihood of DNA replication mistakes being repaired.
This implies that mutations might accumulate over time, potentially leading to cancer, especially in the intestine.
According to the NHS, approximately fifty percent of persons with Lynch syndrome will go on to get colon cancer.
The charity Bowel Cancer UK estimates that Lynch syndrome causes 1,200 instances of bowel cancer annually.
The disease is also responsible for approximately 1,000 more incidences of cancer in the United Kingdom each year.
Lynch syndrome is expected to cause approximately 4,200 colon cancers and 1,800 uterine cancers each year in the United States.
