Choose an active lifestyle to reduce your cancer risk

Listen to top health experts explore the ins and outs of lifestyle habits that can lower your risk of developing cancer significantly:

• ‘What is cancer?’, here.
• The Cancer Journey’, here.

According to the American Cancer Society, 38% of women and 42% of men will be diagnosed with an invasive cancer in their lifetimes. While a small percentage of these are linked to genetic factors, it’s proven that environmental factors and lifestyle are the major contributors towards cancer developing. Studies clearly demonstrate the significant role of an active lifestyle in reducing your risk of developing cancer, especially when combined with other healthy choices such as not using tobacco products, moderate alcohol intake, a healthy diet and avoiding behaviours that increase exposure to oncogenic (cancer-causing) viruses. Find out more about these viruses here and here.

“Over the past 10 years, the high number of large scientific and cancer epidemiology studies that have been carried out, allow us to draw more definite conclusions about the effects of lifestyle interventions when it comes to cancer prevention,” says Sports and Exercise Medicine Physician, Dr Jon Patricios. “Now, more than ever before, we can be certain about the beneficial effects of exercise - so much so that the US Physical Activity Guidelines Committee has just released its 2018 scientific report with an entire chapter dedicated to cancer prevention!”

"No pill can come close to replicating the benefits exercise provides." - Dr Jon Patricios.

“For me the greatest motivator is that regular exercise provides a greater range of benefits,” adds Dr Patricios. “And it provides more impact on sustainable health than any other life or pharmacological intervention – impact on everything from weight loss to cancer prevention. No pill can come close to replicating the benefits exercise provides.”

Cancer-beating exercise facts that will get you moving

“A wealth of evidence has shown that regular physical activity is associated with a host of benefits, including a lower risk of developing cancer and other chronic diseases (such as Type 2 diabetes and cardiovascular disease), as well as reducing the risk of cancer recurrence and death,” says Dr Patricios. “There’s no doubt that lazy lifestyles are dangerous and that being sedentary actually predisposes you to certain types of cancer such as uterine, colon and lung cancers. There’s also a particularly strong relationship between regular exercise and a lower incidence of cancers of the bladder, breast, colon, oesophagus, stomach, kidney and uterus. The risk reduction of being physically active alone is about 20%, but when combined with other healthy lifestyle choices, you could be reducing your risk by as much as 60%! It’s interesting too,” he continues, “That some studies have linked exercise to a higher rate of melanoma (an aggressive form of skin cancer) but this is probably due to the effects of sun exposure when exercising outside. So a word of caution when you do venture outdoors: always use high factor sun block and wear appropriate clothing including hats.”

How does exercise exert its protective effect?

There are a number of ways that being physically active can lower your cancer risk, says Dr Patricios. These include:

• Chemical control

Hormones are chemical messengers that control most bodily functions. Some cancers are influenced by hormone levels. Exercise helps to lower the levels of the hormone oestrogen which is associated with breast and uterine cancers. Insulin, the hormone that regulates blood glucose levels and influences how cells use food and store energy, is significantly reduced by exercising regularly. High insulin levels may turn on signals that cause cancer cells to multiply so lowering insulin levels may also reduce this risk. As an added benefit, exercise may help to lower your chances of becoming obese - as obesity may lead to insulin resistance.

• Inflammation and immunity

Inflammation is the immune system’s natural and protective response to injury and infection. The process works to heal wounds, repair damaged tissue or defend the body against viruses and bacteria. But excessive or chronic inflammation – which happens when an inflammation response lingers too long or occurs in places where it should not, triggering an immune attack there – has been linked to the development of chronic diseases in the body, and this low-grade, long-term inflammation has an effect on the whole body. Chronic inflammation creates an environment in which cellular DNA can be damaged, and in which tumour cells can survive and multiply. But regular, moderate levels of exercise may help regulate harmful inflammation and boost immunity. Read more about inflammation in this Johns Hopkins review.

• Gut guarding

Exercise helps your bowel to become more active and moves food more efficiently through your gut, which means that any food that may contain potentially harmful substances remains in contact with your gut lining for a shorter period of time.

What is “regular exercise”?

“The beneficial effects of exercise become apparent when your heart rate is raised for at least 30 minutes most days of the week,” explains Dr Patricios. He offers the following guidelines:

• The current recommendation for substantial health benefits according to The American College of Sports Medicine (ACSM) and the Center for Disease Control (CDC), is to exercise moderately for at least 150 minutes every week.
• Try to ensure that any forms of aerobic activity to get your heart rate up are spread throughout the week
• Aim to include muscle-strengthening activities that are moderate- or high-intensity and involve all major muscle groups such as Pilates or yoga, on two or more days a week, as these will provide additional health benefits
• Stay focussed and injury-free by starting out slowly and progressing very gradually when it comes to how long you exercise for, how often and at what intensity. While increasing both duration and intensity will be highly beneficial, it’s important to remain injury-free
• Always listen to your body and exercise according to your age and fitness level, and never embark upon any new form of exercise programme without the prior approval of your health practitioner.