When the World Health Organization recently issued a report saying processed meat is a carcinogen and red meat is a probable carcinogen, the world took notice. Diets rich in processed meat (such as hot dogs, ham, bacon and sausage) definitely increase cancer risk. Diets rich in other red meat (such as beef, veal, lamb and pork) may increase cancer risk. The strongest evidence was for colorectal cancer, but pancreatic, stomach and prostate cancers were associated as well.
WHO's International Agency for Research on Cancer, a group of 22 experts from 10 countries, based their conclusion on a systematic review of about 800 human studies on diet and cancer. Evidence comes from epidemiological research, studies involving large swaths of people more ideal for addressing public health concerns than determining what any one individual should eat. And that's exactly what the WHO report is meant to do: help governments make population-wide recommendations.
What the WHO Study Means
Is processed meat really a public health threat? Well … yes. When you consider that eating 50 grams a day of processed meat — about two slices of ham or bacon — increases colon cancer risk by 18 percent. And, when you consider that many people worldwide eat many slices of ham and bacon, the numbers add up quickly. About 34,000 cancer deaths a year worldwide can be attributed to eating processed meat, and potentially even more to eating other red meat.
What the WHO Study Does Not Mean
None of this means you will get cancer if you eat a slice of pepperoni pizza, and you won't if you don't. Cancer is more complex than that. You could eat all the vegetables, exercise every day, never smoke a cigarette, have no family history of cancer, and still develop the disease. Harsh truth, but don't you want to improve your odds? Diet and lifestyle do matter. The American Institute for Cancer Research estimates that 33 percent of breast cancer cases (that's 76,500 people) in the United States could be avoided with lifestyle-related changes.
And, nutrition clearly plays a large role in obesity, which has been linked to about 10 different types of cancer and may soon surpass tobacco use as the number one modifiable contributor to cancer among Americans. The National Cancer Institute estimates obesity will lead to about 500,000 additional cases of cancer in the United States in the next 15 years.
So, should you stop eating red meat or processed meat? As a vegetarian and a firm believer in the many benefits of plant-based diets, you won't ever hear me say eating meat is a good practice. But, if you don't want to give it up entirely, no one, including the WHO, is saying you must.
Just. Have. Less.
So what's the advice? Moderation, folks. More beans, less beef. Achieve and maintain a healthy body weight. Exercise.
This is old news, though admittedly not a sweeping, sexy, or profitable statement.