By Aretha Persaud, MD

Family Medicine, Primary PartnerCare Physicians

Date:  February 27, 2024

Almost 8 years ago, in an alarming announcement, the World Health Organization (WHO) announced that eating processed meat is carcinogenic to humans and eating red meat was determined to be “probably carcinogenic”.  The study included 22 scientists from ten countries, and its conclusions were primarily linked to colorectal cancer. However, data also showed positive associations between processed meat and stomach cancer and between unprocessed red meat consumption and pancreatic and prostate cancer.  In fact, the WHO classified Processed Meat as a Group 1 carcinogen, the same category as tobacco smoking and asbestos!

“Processed Meat” was defined as meat that has been transformed through salting, curing, fermentation, smoking or other processes to enhance flavor or improve preservation.  “Red Meat” was defined as unprocessed mammalian muscle meat such as beef, veal, pork, lamb, mutton and goat meat.

The carcinogenic facts:

• Curing meat by adding nitrates or nitrites can lead to the formation f potentially cancer-causing chemicals N-nitroso-compounds (“NOC”) and polycyclic aromatic hydrocarbons (“PAH”), as can  the process of smoking meat
• Cooking at high temperatures, including over a flame, can also produce carcinogenic chemicals including heterocyclic aromatic amines (“HCA”) and PAH. Fried bacon contains more HCAs than any other cooked meat!
• Meat itself contains heme iron, which can facilitate production of NOC

Meat lovers beware. The 2015 study reported that 50g/day of processed meat can increase one’s risk for colorectal cancer. If you are wondering, 50g is about 6 slices of bacon or 1 hot dog. Later research found increased risk of cancer for every 25g of processed meat eaten per day. The risk reported is based on the population average, but if you are already at high risk for disease due to factors such as obesity, lack of physical activity, consumption of high amounts of sugar or saturated fat or are just genetically more susceptible, your absolute risk is even higher.  The consumption of Processed Meat and Red Meat is also associated with higher risk of heart disease and diabetes, not just colorectal cancer.

Recent research led by Harvard T.H. Chan School of Public Health demonstrates the frequent consumption of Processed Meat and Red Meat found a specific pattern of DNA damage, known as mutational signature in colorectal tumors. This “alkylating’ damage was caused by specific compounds that are produced in the body after the consumption of Red Meat.

Researchers recommend thinking of Processed Meat and Red Meat as “lobster”, saving it for special occasions but not part of our day-to-day diets.

I love meat so what can I do?

• Try Meatless Mondays and make it fun for you and your family
• Find new recipes that use fresh chicken or fish
• Reduce your portion size of meat such as 1 sausage instead of 2; learn to add additional veggies and use the sausage for flavor only