8 proven steps to lower your risk of getting cancer
More aspirin, fibre, yoghurt and marinating your meat can all help to lower the risk of cancer. Our reporter investigates.
It has been long known that cancers are caused by a combination of our genes, diet and lifestyle. However, as we gradually understand more about epigenetics - the way our genes are switched on and off by factors in our environment - the more we will discover about what we can do to help turn on genes linked with cancer protection, and switch off those linked with causing it.
Indeed, though the research is still in its early days, epigenetics may one day identify the exact lifestyle and dietary factors that could prevent cancer. Until then, however, here is what is already known and proven to lower your risk.
Our gut bacteria or micro-biome has recently been linked to everything from mood to obesity, and a growing number of studies are now linking it to a lowered cancer risk.
The latest, published last month in the journal PLOS One, gave one group of mice beneficial bacteria through probiotic supplements and the other non-beneficial bacteria.
The mice receiving the good bacteria produced metabolites known to prevent cancer in their guts and were also better able to metabolise fats, which the researchers said could help lower the risk of cancer.
"The results are positive and that's probably because the microbes help break down some of the toxins in the gut that might normally cause cancer, but also because they keep the immune system in great shape generally so it beats off cancer cells," says Tim Spector, professor of genetic epidemiology at King's College London, founder of the British Gut Project and author of The Diet Myth.
To keep your gut bacteria healthy, eat a mix of probiotic foods such as live yoghurt, kefir (fermented milk drink) and sauerkraut as well as prebiotic foods such as fruit, vegetables and high fibre whole grains and legumes to feed bacteria and help it grow, Prof Spector explains.
Take an aspirin
While it has been known for a while that a low-dose aspirin a day may help prevent the risk of heart attack, the latest evidence suggests it could also help prevent colorectal or bowel cancer, which strikes over 2,300 Irish each year.
In April, the United States Preventative Service Task Force updated its guidelines to recommend all adults aged 50-59 should take a low dose aspirin for 10 years.
Though Ireland is yet to follow, many medical experts are convinced of aspirin's benefit.
"The evidence is strong that taking aspirin for five years or more reduces the risk of developing bowel cancer," says Professor Peter Johnson, professor of medical oncology at the University of Southampton and chief clinician for Cancer Research UK.
"It's also been found that people who do get cancer are at less risk of having it spread if they take aspirin."
If there is an inherited tendency toward bowel cancer, taking a low-dose aspirin is a good idea, he suggests. "Aspirin may work by reprogramming the way the immune system works, affecting the inflammation pathways in the lining of the gut, and thus helping it to recognise very early cancers and remove them," Prof Johnson says. But it comes with risks, such as bleeding from ulcers in the stomach, so always consult a GP first.
Marinate your meat
In the 1990s the biggest study into nutrition and cancer began tracking the diets of 500,000 healthy people aged 45-79 across 10 countries in Europe to see who would get cancer.
Among the key findings from European Study on Diet and Cancer (EPIC), were that processed and red meat are associated with a higher risk of developing bowel and stomach cancers.
Current recommendations suggest sticking to 70 grams a day (about two rashers of bacon) and according to CRUK, this one change alone could prevent the staggering number of bowel cancer cases each year.
Research also suggests charred or well-done meats may be associated with increased risk because of cancer-causing heterocyclic amines (HCAs) which form when meat is cooked at high temperatures.
But meat lovers don't despair, fascinating research from Kansas State University found that marinating meat in herbs such as rosemary, thyme, oregano, basil, sage and marjoram before cooking can lower the HCA components in meat (so could taking the skin off chicken).
Go for fibre
Simply increasing your fibre and your fruit and vegetable intake to five portions a day could help prevent 14 different types of cancers, the EPIC study found.
Increasing your intake of fibrous whole grains such as oats, brown rice and wholemeal bread was particularly associated with a lowered risk of bowel cancer and some research has suggested it may help prevent breast and prostate cancers too. It's not certain how it happens but some speculate that this also might be linked to gut bacteria.
"Studies like EPIC show consistently that people who eat lots of fibre, fruit and vegetables have low levels of cancer and the reason could be that these people consequently have a healthy gut microbiome that helps the immune system fight off cancers," says Prof Spector.
Know the new sun rules
While we know that wearing sunscreen not only helps prevent burns, but also malignant melanomas - a survey last year showed one-in-five Irish adults was unaware that the SPF rating does not mean protection against all sun damage - only that from UVB rays which cause sunburn and are denoted by the SPF or factor on the bottle (researchers suggest at least a factor 30).
Ultraviolet A rays (UVA) penetrate the skin more deeply, so also look for the level of UVA protection (denoted by a UVA star rating or the letters UVA inside a circle) as well.
When covering up, Spanish research found that blue and red fabrics offered better sun protection than white or yellow ones. It's also crucial to protect areas where sun hits as these are where most cancers develop.
Think bald heads and torsos in men and or exposed calves in women and be mindful to protect children as those who have been exposed to sunburn are more likely to develop skin cancer as adults.
Lose 10 pounds
Some 66pc of Irish men and 50.9pc of Irish women over the age of 20 are considered overweight or obese according to the Lancet - well in excess of the western European average of 47.6pc.
"The heavier you are the greater your risk of [breast, liver, womb, prostate and pancreas] cancers," says Prof Bauld, who explains that even if you're more than 20 pounds overweight, any weight loss will lower your risk.
Last month, the World Cancer Research (WCRF) released new evidence linking obesity with stomach cancer, which is now the third biggest cancer killer in the world.
Spread your alcohol load
When earlier this year, chief medical officer Dame Sally Davies changed weekly recommendations to 14 units for both men and women, the key reason was the link between even low alcohol consumption and seven types of cancers including those of the breast, liver, bowel, mouth and throat (the WCRF's research recently linked three or more drinks a day to stomach cancer too).
"The risk of cancer starts at even low levels of alcohol so it's best to stick to just one glass a night," Prof Bauld says.
How about saving up all your units for a special occasion? "Alcohol is ethanol which is metabolised into a substance called acetaldehyde which the body finds difficult to process," she explains.
"High levels cause dehydration which makes cells more vulnerable to multiplying, and this effect is greater the more alcohol you drink on one occasion."
The EPIC study found that those who did 30 minutes of exercise each day had a lower chance of developing cancer and being more active could prevent all new cases of breast, bowel and womb cancers in the UK.
"It improves hormone levels which can help reduce a woman's risk of developing breast and womb cancer," says Prof Johnson.
"It also helps transit times in the intestine, helping food move through faster so there's less chance of inflammatory reaction in the bowel which is how it lowers bowel cancer risk." © Daily Telegraph