Walking twice a day could significantly reduce bowel cancer risk, study finds

A recent study has shown that engaging in physical activity twice a day, at 8 AM and 6 PM, may reduce the risk of developing bowel cancer by 11%. The research team wrote in the study published in the journal BMC Medicine: "People who were active in both the early morning and evening were 11% less likely to develop bowel cancer."

The study was led by experts from the University of Regensburg in Germany, with Professor Dr. Michael Leitzmann as the lead investigator. Professor Dr. Michael Leitzmann, chair of the department of epidemiology and preventive medicine at the University of Regensburg, used data from the UK Biobank, which includes genetic and health information from more than half a million Britons. The UK Biobank's database is being used to unlock the secrets of human health.

The study analyzed health data from over 86,000 people aged between 42 and 79 years. All participants' physical activity was tracked by wearing a wrist device known as an accelerometer. During a follow-up period of more than 5 years, 529 participants developed bowel cancer.

The researchers highlighted four patterns of activity: continuous activity throughout the day, activity late in the day, activity in the early morning and evening, and activity at noon and at night. They found that engaging in physical activity twice a day, in the early morning around 8 AM and at 6 PM, was associated with a reduced risk of bowel cancer, exceeding the benefits of physical activity in general. Those who were active in both the early morning and evening were 11% less likely to develop bowel cancer.

Being active throughout the day reduces the risk of bowel cancer by six percent. The health benefits of walking at these times were greater than for other patterns of exercise, such as being active all day or only at night. There was no change in colorectal cancer risk for those active in the middle of the day and at night. Data from those who were active later in the day only was inconclusive.

The study found that the results were consistent even when considering factors such as smoking, working night shifts, and other variables that may affect people's cancer risk. The researchers noted that highlighting specific times when physical activity is "more beneficial" may pave the way for better cancer prevention strategies. Lead investigator Professor Dr. Michael Leitzmann said: "By identifying specific times—early morning and late day—when physical activity is most beneficial, our findings open new avenues for targeted prevention strategies." He also stated: "This could provide a simple yet impactful way for individuals to further reduce their cancer risk."

Walking to and from work, or taking strolls after breakfast and before dinner, could improve health. It is thought early morning exercise starts the body clock for the day and is good for the circadian rhythm. Being active at similar times each day has been linked to less disruption to the circadian rhythm.

Dr. Helen Croker, assistant director of research and policy at the World Cancer Research Fund, said: "Being physically active is one of our cancer prevention recommendations, and we know that this cuts cancer risk." She added: "These intriguing new findings offer potential for developing more specific recommendations, including patterns and timing of physical activity, for reducing cancer risk."

Bowel cancer, also known as colorectal cancer, is one of the most common forms of cancer in the UK, with around 44,000 cases per year, making it the fourth most common cancer in Britain. Between the early 1990s and 2018, the number of adults aged 25 to 49 being diagnosed with bowel cancer increased by a fifth in the UK. Bowel cancer can develop anywhere in the large bowel, which includes the colon and rectum.

Symptoms of bowel cancer include a persistent change in bowel habit, such as going to the toilet more often with looser stools and sometimes tummy pain. Other symptoms include blood in the stools without other symptoms such as piles, abdominal pain, and discomfort or bloating always brought on by eating.

It is well known that exercise and staying fit reduce the chances of developing tumors. Millions of people in the UK do not manage to do the recommended amount of exercise, which is 2.5 hours per week.

The findings were published in the journal BMC Medicine.

Sources: The Sun, The Scottish Sun, The Guardian, Mirror, Asharq Al-Awsat

This article was written in collaboration with generative AI company Alchemiq