The recent World Health Organization report declaring processed meat a carcinogen has caused quite the uproar. Consumers are yelling, “don’t ruin bacon for us!” while the meat industry is fighting back, saying the report takes meat’s role in the diet out of context. Meanwhile, health conscious consumers and groups like the American Cancer Society and the World Cancer Research Fund agree — this is old news.
And it is old news. The WHO didn’t do any new, original research; instead, they analyzed over 800 studies that looked at the correlation between red and processed meat intake and cancer. After reviewing the evidence, they placed processed meat — such as bacon, cured sausage, hot dogs, and ham — in the Group 1 category of carcinogens, meaning there is “sufficient evidence” they cause cancer. While this is the same category that cigarettes and alcohol are in, the category only describes the strength of the evidence, not the magnitude of the risk. So while the WHO is sure that these substances cause cancer, the level of risk is different. For processed meats, eating 50g/day (about 5 slices of bacon) increases your lifetime risk of developing colorectal cancer by about 18%, or 1.18x. Smoking on the other hand increases your lifetime risk of developing lung cancer by 20x.
Think about it this way–eating bacon everyday is like driving your car everyday: it increases your risk of getting into a car crash and dying. Smoking is like heavily speeding everyday, increasing your risk of dying in a car crash much more. While both activities will increase your risk of dying, speeding (smoking) is much riskier than normal driving (eating processed meat).
Red meat’s connection with cancer is less certain, but still probable. The evidence for the connection between red meat like beef, pork, and lamb and cancer is in the Group 2 category, so it’s “probably carcinogenic.” While the evidence isn’t as strong as the evidence for processed meat, the WHO estimates that eating 100g red meat/day (about 3.5 oz) also increases your risk for colorectal cancer by 18%. How likely are you to develop colorectal cancer? It’s about 5%, varying depending on your age and sex.
Groups that represent the meat industry are quick to point out that these increases in risk are modest, especially compared to cigarettes or alcohol. Taken in context, they say, meat’s benefits to health outweigh the harm.
Let’s take a real life look at what these figures mean to our health. While the increase in risk is modest, they still mean that diets high in processed meats can account for 34,000 cancer deaths per year worldwide, according to the Global Burdens of Disease. Diets high in red meat can account for 50,000 cancer deaths worldwide. These numbers just account for deaths, not cancer occurrence that might be attributed to red and processed meat. Suddenly that bacon cheeseburger isn’t looking so appealing.
Let’s take a further look at that bacon cheeseburger. While the bacon slices on the cheeseburger might amount to less than 50g (or 5 slices), the hamburger patty is almost sure to be 4 oz or greater. If a person consumes the equivalent of a bacon cheeseburger everyday, they theoretically increase their risk of developing colorectal cancer by 36%. The more a person consumes, the higher their risk.
The meat industry is right, we shouldn’t look at meat’s influence on our health in a vacuum. In appropriate context, we should also consider the heavy dose of saturated fat and salt found in processed meats – both of which contribute to heart disease. While these meats also provide protein and iron, so do many other foods. Not to mention the cost that growing red meat has on our environment.
The take home message is simple. If you’re worried about cancer and eat red and processed meat every day, cut back. Limiting it to once or twice a week is a safe bet. Your health and the health of the planet will thank you.