We’re learning more about the lifestyle factors that protect against cancer, so here are smart steps you can take to reduce your risk. By Stephanie Osfield.
It’s a sad but true fact that cancer will touch the lives of most of us at some stage: In Australia, one in two men and one in three women will be diagnosed with cancer by the age of 85. But you can take steps to help protect yourself.
Though there is no anti-cancer diet, growing evidence suggests that our food choices can help protect our bodies from cancer. “Foods that are high in antioxidants and fibre, such as fresh vegetables, fruit, whole grains and legumes (e.g. chickpeas and lentils) can reduce cancer risk,” says Alan Barclay, dietitian and Chief Scientific Officer of the Glycaemic Index Foundation.
“Foods such as white bread, pastries and potatoes are best minimised as they increase your levels of blood glucose. And this makes the body pump out more insulin,” Barclay explains. “This hormone increases cell growth and decreases cell death, which raises the risk of developing some types of cancer.”
Cancers related to our diet are often found in the digestive tract, including the oesophagus, stomach and bowel, says the Cancer Council.
Other lifestyle factors such as smoking, weight gain and sun exposure may also contribute to cancer risk.
“One in three cancer cases are linked to lifestyle risk factors and can be prevented,” Professor Sanchia Aranda, CEO of Cancer Council Australia points out. That’s reason enough to give your habits a cancer-fighting makeover.
1. Maintain a healthy weight
“Being overweight increases your risk of developing bowel and breast cancer (after you reach menopause), as well as cancers of the endometrium, kidney and oesophagus,” says Prof Aranda. “Research estimates that 3900 cancer cases each year in Australia are linked to being overweight or obese.”
So, it’s important that you regularly monitor your weight. Your GP can assess your body mass index (BMI), where a score of over 25 is classed as being overweight. And, your waist circumference should be below 94cm (for men) and below 80cm (for women).
If you’re one of the 62 per cent of Australian adults who are overweight, see an accredited practising dietitian for a healthy way to lose weight. “Avoid rigid diets, which have been shown in studies to be unsustainable and actually cause weight gain in the long term,” says Melanie McGrice, a dietitian and director of Melbourne’s Nutrition Plus.
2. Follow the plant plan
Vegetables are packed with vitamins, minerals and fibre. And eating seven or more servings of vegetables and fruit every day has been found to reduce risk of death from any cause (including cancer) by 42 per cent. Research by Loma Linda University in California, US has found that vegetarians enjoy a 22 per cent lower risk of colon cancer.
Vegies also offer protection against lung cancer, one of the most common cancers (with many cases unrelated to smoking). “A very low intake of fruits or vegetables is linked to a three-fold increased risk of lung cancer,” says Barclay. “And foods like berries, citrus fruits, tea, dark chocolate and red wine are high in flavonoids, which may also reduce lung cancer risk.”
3. Limit your saturated fats
If you eat a large amount of saturated fats from red meat and full-fat cream and cheese, you may bump up your risk of developing cancer of the breast, pancreas, prostate, and bowel, shows research. “There is a particular link between red meat and certain bowel cancers, and processed meats such as bacon, ham and sausages increase risk the most,” explains Barclay. “This may be because they contain a preservative called nitrate that irritates the gut.”
The Cancer Council suggests that you eat red meat no more than two or three times a week, choose lean cuts and small portions, and eat more chicken, fish and pulses as protein sources. “Processed meats should not be eaten more than once a week,” Barclay adds.
4. Get moving
Hitting the gym, pounding the pavement or lapping the pool may be protective against colon, breast, pancreatic, endometrial and prostate cancer, shows research. “Some studies estimate that a more active lifestyle may reduce the risk of colorectal cancer by 40–50 per cent, and lead to a 30–40 per cent risk of breast cancer,” says Dr Catherine Granger, from Physiotherapy at The University of Melbourne and Royal Melbourne Hospital.
“To reduce cancer risk, many organisations like the American Cancer Society recommend adults include a minimum of 150 minutes of moderate intensity exercise per week or 75 minutes of vigorous intensity exercise per week.”
5. Watch your alcohol intake
Drinking any type of alcohol (beer, wine or spirits) increases the risk of developing cancer of the bowel, mouth, pharynx, larynx, liver, oesophagus and breast. “The more alcohol you consume, the greater your risk of developing cancer,” says Prof Aranda.
If you do choose to drink, follow the National Health and Medical Research Council guidelines and limit your intake to two standard drinks a day. “Women should be aware of evidence that just one drink a day could increase their risk of breast cancer,” warns Prof Aranda.
6. Stop smoking
Tobacco smoke contains more than 7000 chemicals, and over 70 of them are known to cause cancer, says the Cancer Council. As soon as you quit, there are immediate and long-term health benefits. To kick the habit, see your GP about medication and nicotine patches, and contact Quitline via icanquit.com.au or phone 13 78 48.
7. Don’t rely on supplements
Supplements lack the diverse range of phytonutrients that are found in food, and it’s the combination of these nutrients that appears to boost your body’s defences against cancer. “Supplements may also have unexpected impacts,” warns Barclay. “In one study, male smokers were given beta-carotene supplements. These ended up increasing the risk of cancer, which was an unexpected result. This is a good reminder that supplements are no substitute for healthy, whole foods.”
8. Check your pill
Taking the contraceptive pill has been linked to a slightly increased risk of breast cancer (of about one additional case per year for every 100,000 women), shows research published in The Lancet medical journal. However, studies also show some protective effects against cancers of the ovaries and endometrium. See your GP to discuss your risks in relation to your age, lifestyle and family history.
9. Don’t be afraid of soy foods
Based on current evidence, moderate consumption of soy foods, as part of an overall healthy diet, is unlikely to have any harmful effects for most people, says the Cancer Council. “However, women who have breast cancer should avoid a diet high in phytoestrogens, found in soy, as the safety of soy in relation to breast cancer is still not clear,” says Prof Aranda.
10. Up your fibre
In the future, doctors may prescribe high-fibre diets to boost healthy gut bacteria. A healthy bacteria balance may help prevent and treat cancer, shows a growing body of studies, including research from the University of California. “While all fibre is beneficial, resistant starch is a type of fibre that is particularly helpful. This is because the beneficial bacteria in the colon uses it as food,” says Dr Jane Muir, Head of Translational Nutrition Science in the Department of Gastroenterology at Monash University. According to the CSIRO, good sources of resistant starch include chickpeas, oats and bananas.
Checking for changes in your breasts
Get to know the usual look and feel of your breasts so that you notice any differences, says the Sydney Breast Cancer Institute. Check regularly for any changes by:
Using the flat pads of your fingers and small circular movements, touch your breasts up to the collarbone and out to the underarm. Do this while you are showering and also when lying down.
Place your hands by your sides and check your breasts in a mirror, looking for changes in colour, size or shape, any dimpling of the skin, ‘pulling in’ of the nipple or unusual discharge.
Check your breasts at the same time each month (preferably 2–3 days after your period ends or on the first Monday of each month if you no longer menstruate). If you notice any changes in your breasts, have them checked by your doctor. And don’t skip regular professional examinations by your GP or screening mammograms.
Did you know?
The main risk factor: A diet that’s rich in antioxidants is better protection against cancer than any vitamin tablet. And it’s actually the combination of the nutrients found in food that appears to boost your body’s defences against cancer. “Supplements are no substitute for healthy, whole foods,” says Alan Barclay, dietitian and Chief Scientific Officer of the Glycaemic Index Foundation.
The big picture: New cases of cancer in Australia increased from 47,417 in 1982 to 118,711 in 2011, a rise of 60 per cent. According to the Australian Institute of Health and Welfare, the most commonly diagnosed cancers are prostate, bowel, breast, melanoma and lung cancer.
The good news! After cancer diagnosis, people are surviving much longer and are in better health. “An estimated 67 per cent of Australians diagnosed with cancer will still be alive in five years’ time,” says Prof Aranda. “This is a significant improvement from the 1980s, when the survival rate was 46 per cent.”
Earlier detection: As well as advances in treatment and research, “the improvements in cancer survival rates are also due to early detection from better screening programs, such as those now in place for cervical, bowel and breast cancer,” Prof Aranda explains. So, keep up-to-date with your scheduled check-ups.