Eating even a little bit of processed meat regularly can increase your risk of some deadly cancers
Eating red meat and processed meat has been linked to higher cancer rates.
But research is increasingly finding that processed meats are much worse for you than other kinds.
The average omnivore may be consuming more processed meat than is healthy.
Here’s what to know when you’re shopping.
If you look closely, the potential for cancer lurks in almost everything we touch and eat, from the plastics we store food in to the receipt paper we touch in the checkout line. That can all make avoiding unhealthy foods feel like a hopeless endeavour.
But increasingly, scientists are pointing out a few simple items you should avoid if you’re worried about cancer risk.
A growing body of research shows that regular consumption of processed, cured, or smoked meats including ham, hot dogs, bacon, and sausage can up your odds of developing some deadly cancers. That is largely because processed meats are treated with nitrates – chemical additions that help keep the colour of the meat pink and the flavour tasty and salty.
“If no one ate processed or red meat in Britain, there would be 8,800 fewer cases of cancer,” The Guardian reported earlier this year.
Nibbling a piece of bacon at brunch or chowing down on the occasional hot dog at a ballgame isn’t going to kill you, of course. But here’s why you shouldn’t consume meat that’s been salted, cured, or treated with preservatives on an everyday basis.
Processed food in general has been linked to some deadly cancers
A recent French study of more than 100,000 people found that eating more processed food of any kind – including processed meat, sugary drinks, packaged snacks, and prepared frozen dinners – was more closely linked with cancer risk than family history, body-mass index, or even smoking and drinking habits. The researchers couldn’t conclude for sure that processed food causes cancer but found it to be the most likely culprit.
“A 10% increase in the proportion of ultra-processed foods in the diet was associated with significant increases of 12% in the risk of overall cancer, and 11% in the risk of breast cancer,” the researchers said.
When it comes to red meat, unprocessed cuts like a fresh steak or a slice off a pig’s belly haven’t conclusively been linked to cancer. Processed meat, however, has.
According to the International Agency for Research on Cancer, the average eater of red meat consumes about 500 to 100 grams of meat each day. If all that meat is processed, meat eaters see their cancer risk rise by 18%.
This is not a new finding. Dr. Philip Hartman, a cancer expert and biology professor at Johns Hopkins University at the time, told The New York Times back in 1981: “I personally feel cured meat is 9 or 10% of the problem of gastric cancer, and that is not insignificant.”
Processed meat is prepared so that when you’re ready to eat it – whether a few minutes, hours, days, or weeks after you buy a product – the food will be unspoiled, salted, and ready for consumption. But that convenience can have consequences.
“Meat processing such as curing and smoking can result in formation of carcinogenic chemicals including N-nitroso compounds and polycyclic aromatic hydrocarbons,” the IARC says.
These compounds include nitrates, which occur naturally in water and some foods but are used artificially as preservatives. Nitrates widen our arteries, and some (like those found naturally in beets) may even boost athletic performance. But too much nitrate in the body can lead to a condition called methemoglobinemia, in which a person’s blood is not as effective at moving needed oxygen into tissues. It can make one’s skin turn bluish and lead to headaches, shortness of breath, and fatigue.
“Studies have shown increased risks of colon, kidney, and stomach cancer among people with higher ingestion of water nitrate and higher meat intake” the National Institutes of Health says on its website. “Other studies have shown modest evidence that higher nitrate intake can increase the risk of thyroid cancer and ovarian cancer among women.”
A 2018 roundup of studies performed on more than 1.2 million women around the world found those who ate processed meat regularly had a 9% higher risk of developing breast cancer, a small but noticeable increase.
If you’re trying to avoid nitrates when shopping, it’s important to remember that even processed meats labelled as nitrate-free can still have natural nitrates in them from added cane sugar, celery juice, or beetroot juice, as The Times recently reported.
When processed meats are grilled, fried, or blackened, cancer risk goes up
Adding fire to the mix makes processed meats even more dangerous. For example, the nitrates that help preserve bacon easily turn to nitrosamine, a known cancer-causer, when it’s fried. (Even if bacon isn’t fried, nitrates can also turn to nitrosamine in our acidic stomach juices.)
According to the National Cancer Institute, this isn’t just a problem for processed meat. When beef, poultry, or fish is cooked over an open flame or pan-fried at high temperatures, the fat and juices those meats release can spark flames that contain dangerous chemicals, which then cook into the meat we eat. Pan-frying, grilling, and barbecuing are some of the most carcinogenic ways to prepare meat, according to the IARC.
Research into the risks of eating processed meat is part of a larger scientific effort to pinpoint our most harmful eating habits.
Colon and rectal cancer rates are soaring in people ages 20 to 49. Researchers aren’t sure why this group is developing bowel cancer at double the rate seen just three decades ago, but diet could be part of the problem. Packaging could also be an issue: Plastic wrapping for food can include bisphenol S, or BPS, which can disrupt normal functioning of the endocrine system in animals.
The one piece of advice most nutritionists agree on is that increasing the amount of fresh produce you eat is a good choice. A 2012 analysis published in the journal Food and Chemical Toxicology estimated that about 20,000 cancer cases could be prevented every year if Americans just ate additional servings of fruits and vegetables each day.