Active commutes lower cancer risk

Cycling or walking to work will reduce your risk of several types of cancer, according to new research out of Waipapa Taumata Rau, University of Auckland.

While earlier studies had established exercise reduced the risk of a number of cancers, they hadn’t specifically looked at how people travel to work, with active transport a sure way to meet health guidelines for exercise.

“It is one thing to say that people should be encouraged to be more physically active but simply telling them to ‘exercise more’ often doesn’t stick,” says Professor Alistair Woodward, an author of both studies and a public health researcher at the University of Auckland.

“Life is busy, and advice given in isolation rarely leads to lasting change. Using regular commuting as the vehicle for getting physical activity into people’s lives, is far more likely to lead to sustained change.”

In the first of two recent studies, lead author Dr Win Thu and colleagues examined 27 recent studies to establish that walking and/or cycling to work reduces the risk of breast cancer by 12 percent, endometrial cancer by 30 percent and colorectal (bowel or colon) cancer by 11 percent. See Environmental Health.

The latest study, using more than 250,000 health and life-event records from the UK Biobank and correlated with similar anonymised records for the population of Aotearoa, New Zealand, found dramatic reductions for a number of other cancers with active transport, walking or cycling, to work.

Published in the International Journal of Epidemiology, the study found cycling to work was linked to a lower risk of colon cancer (28 percent), kidney cancer (40 percent) and stomach cancer (73 percent).

Walking to work was also associated with reduced risks of kidney cancer (33 percent) and liver cancer (45 percent).

There were signs cycling may help prevent other cancers too, but the evidence wasn’t strong enough to be conclusive, probably because fewer than 8 percent of participants were regular cyclists.

Dr Sandar Tin Tin, a public health researcher at the University of Auckland, says, “In light of these findings, active commuting should be promoted as an effective lifestyle intervention to prevent cancer and support better health and a cleaner environment.”

Woodward, who leads the University of Auckland’s health and transport research team, says: “Most research on active commuting has focused on heart disease, not cancer. Dr Win Thu’s work helps fill that gap by looking at common cancers that may be less likely in people who are more active.”

Earlier research out of the same team found that cyclists are the happiest commuters, and that cycling is safer than many people think.

“This new study is part of a bigger picture – our transport system is harming health, but it doesn’t have to be this way,” Woodward says.

“According to the NZ Household Travel Survey, two thirds of car trips are five kilometres or less. There’s no good reason we couldn’t match cities overseas where walking and cycling are ten times more common.”

Woodward says research supports the idea that our physical environment shapes our activity, including how we get to work, more than individual advice.

This research shows environments that encourage people to walk or cycle to work will reduce their risk of many types of cancer.