Can you really get cancer from food?

There’s no shortage of articles circulating the media, suggesting that one food is the secret to keeping cancer at bay or that one ingredient we eat regularly causes cancer.

Can you really get cancer from food? We look at five household beliefs linking cancer to food and examine the truth behind the statements.

Preservatives: do they give you cancer?

Preservatives were once our friends. Created to keep food fresher for longer, preservatives are added to food items to prevent them from spoiling. Some preservatives also add flavour and colour to foods.

But in 2015, the International Agency for the Research of Cancer (part of the World Health Organisation) classified two types of preservatives –nitrates and nitrites – found in food as probably carcinogenic’.

In other words, these nitrates and nitrites commonly found in processed meats like bacon and salami might cause cancer in humans.


According to Cancer Council NSW, nitrates and nitrites have been linked to bowel cancer, one of the most common cancers in men and women in Australia. But the risk depends on your exposure. If you eat kilos of bacon every day, your risk will skyrocket. If you eat processed meats rarely or in moderation, then the risk is minimal.

How can we be sure that even a small taste of salami won’t cause us cancer? Food Standards Australian and New Zealand (FSANZ) carries out safety assessments on food additives before they can be made available to consumers to ensure that they are safe and there is a jolly good reason to add them to your food items.

“All such food safety legislative controls in Australia mean that consumers can feel comfortable that the food products available in our country are not associated with an increased risk of cancer,” says Cancer Council NSW in a statement.

Eat well: Not everything gives you cancer, but processed meat can
A new study from the World Health Organisation has grouped processed meats, like bacon and sausages, into the same cancer-causing category as tobacco, asbestos and alcohol. Red meat fared slightly better, but the results raise serious concerns about the modern diet.

Red meat and bowel cancer

Before you believe a headline saying ‘red meat causes you cancer’, ask yourself: what kind of red meat?

If the answer is processed meats, please see above. If you are concerned about unprocessed red meat, say that chunky rump steak you want to eat for dinner or a lamb cutlet, keep reading!

The Cancer Council NSW’s position on unprocessed red meat is that it is “convincingly associated with a modest increased risk of bowel cancer”.

That’s why we are always being told to eat unprocessed red meat – beef, pork, lamb and veal – in moderation.

“On the days where you aren’t having red meat, you can have chicken, fish or a meal with no meat in it. It’s not that hard to achieve a balance.”

Kellie Bilinski, Accredited Practising Dietitian, advises that red meat is fine to eat if you have under the recommended amount of 700 grams per week, as part of a healthy diet full of vegetables.

“It’s a decent amount to consume if you think about it,” says the spokesperson for the Dietitians Association of Australia. “On the days where you aren’t having red meat, you can have chicken, fish or a meal with no meat in it. It’s not that hard to achieve a balance.”

Eat well: The risks of red meat
It's bad news for barbecue lovers – a new study had found too much red meat can give you cancer.



Soy and breast cancer

Some research says soy prevents breast cancer, while other sources online say it might cause it. So which one is it?

Isoflavone, a weak estrogen-like compounds found in plants, is also found in soy foods. Estrogen, in some women, has been found to promote the development, growth, and spread of breast cancers. Hence the fear – if you have breast cancer already, should you avoid eating a lot of soy or taking soy isoflavones as a dietary supplement?

Miso is the processed soy product you actually want to eat
The fermented paste is everything that genetically engineered, unhealthy, environmentally damaging soybeans are not.

Research published in Journal of the National Cancer Institute (2014) shows that in some women, consuming medium amounts of soy – about 52 grams of soy protein or four cups of soy milk – every day could turn on the genes that causes cancer to grow.

But, the study was only short-term so the researchers were unable to conclude whether the genetic changes actually caused the cancer to grow. The study says women shouldn’t avoid soy but instead, only eat it in moderation.

Another study published in the British Journal of Pharmacology in October last year suggests that phytoestrogens (plant oestrogens, found in soy products) could cause infertility and some types of cancer. But again, the results could not overtly say whether phytoestrogens helped or hindered women.

If you are confused now, how about some more research saying that soy may or may not cause cancer? According to the Cancer Council, it’s thought that soy might lower breast and prostate cancer in some Asian countries, where soy is very common in the diet. But overall, there wasn’t enough evidence to suggest that high concentrations of soy in these countries or supplements that contain high doses of soy are effective in preventing cancer in people from Asia.

So basically, right now, there’s no one overwhelming piece of evidence, conducted over the long-term enough on a large enough sample that can conclusively predict the same impact of soy on every single woman’s body.

Sorry folks: the jury is still out on this one. 

Do white grains cause cancer?

Earlier this year, a study was published in JAMA Oncology suggesting that diets high in foods causing inflammation – such as refined grains – could be linked to a higher risk of developing colon cancer. (The key word here is ‘could’.)

The researchers asked over 120,000 people what they ate every four years for 26 years. They found that those who ate inflammation-causing foods, white grains, soft drinks and red meat, were more likely to develop the cancer.

How I joined the cult of sourdough
My carb of choice is definitely bread.

The risk appeared to be higher among overweight or obese men and lean women and among men and women not consuming alcohol.

But despite the flashy headlines associated with the research promotion, the study could not show cause and effect, or isolate one specific food that heightened a person’s risk.


Hot, spicy foods prevent cancer

Ever heard that spicy food is good for you because chillies help prevent cancer? That might be because of a 2015 study, produced by Chinese, US and UK scientists, which suggested that eating spicy food more frequently as part of a daily diet is associated with a lower risk of health-related death.

The researchers looked at almost 500,000 Chinese adults and found that those who ate spicy foods at least once a week were 10-14 per cent less likely to die from health-related conditions than those who ate spicy food less often.

However, the study, published in the BMJ, says that more research is needed to draw wide-ranging conclusions about the impact of spicy food on the body as the findings were quite general and may not apply to people in other countries.

Cancer or no cancer: What should we eat?

“You don’t need to make life difficult and be on an extreme detox diet or eliminate foods from your diet. Instead, just adopt a healthy lifestyle approach to eating.” 

Bilinski advises that Australians stick to a good old-fashioned diet, full of the five food groups. If they maintain a healthy weight, don’t smoke and don’t drink alcohol in excess and eat in moderation, then they are doing as much as they can to lower their cancer risk.

“People should focus on eating a healthy diet,” Bilinski says. “You can enjoy a glass of wine or eat barbecued meat…As long as you are not only having these foods, they aren’t likely to cause you cancer.

“You don’t need to make life difficult and be on an extreme detox diet or eliminate foods from your diet. Instead, just adopt a healthy lifestyle approach to eating.” 

No. Detoxing isn't actually a thing
Alas. The experts claim that no detox plan has the ability to flush out all the bad stuff from our bodies after a seasonal bender.

World Cancer Day

World Cancer Day falls on 4 February every year. 

It offers a chance to raise awareness and reflect about what you can do to make a positive difference in the global fight against cancers - in all their forms. 

For more information, visit the World Cancer Day website

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