Red meat – friend or foe?

Global meat consumption and cancer diagnoses are on the rise. Is there a correlation to red meat? Annica Rust examines this.

Recent studies found an association between a high intake of red meat and/or processed meat products and cancer; especially colon, breast and prostate cancer.³ What does this mean? Do you have to give up red meat completely after being diagnosed with cancer?

Animal foods, such as red meat, fish, poultry and dairy, are good sources of protein, but take into consideration that their fat content varies substantially. The intake of these products will contribute to your daily requirements of iron, zinc, vitamin B12, omega 3 fatty acids (from fatty fish) and calcium (from diary).¹ 

Protein requirements are increased to repair the tissue that has been damaged by cancer treatment. Always try to add a good protein source to each meal which will assist with the prevention of muscle loss. 

When choosing a good animal protein source, we need to take carcinogens, cooking methods, and frequency of portions into consideration.

Carcinogens

Processed meats are classified as a Group 1 carcinogen (cancer causing), which means that there is a definitive link between cancer in humans and the consumption of processed meats. The curing process (adding nitrates or nitrites) or smoking of meat can lead to the formation of N-nitroso compounds or polycyclic aromatic hydrocarbons (PAHs), which are also carcinogenic. 

Red meat (beef, pork, lamb, goat, veal and mutton) is a Group 2A carcinogen, which means that red meat can possibly cause cancer in humans. Unfortunately, the evidence in humans is limited, however, is sufficient in animal studies. There is strong evidence that consuming red meat might increase the risk for colorectal cancer.^1,2 

Heme iron (iron from animal sources) is broken down in our gut to form N-nitroso compounds, which may be associated with an increased risk of breast- and colon cancer. However, evidence is limited and further research is still required.^1,2

Cooking methods

Cooking meat at high temperatures over an open flame can contribute to the formation of heterocyclic amines (HCAs) and PAHs. Normal roasting or frying of meat produces less PAHs when compared to grilling over an open flame.¹

Frequency of portions

To lower the carcinogenic effect, try to consume no more than three portions or 350-500g of red meat (cooked) per week. Take note that 500g of cooked meat is equal to 700-750g of raw meat. Aim to consume at least two portions of fish per week, preferably fatty fish, such as sardines, tuna, salmon or trout.¹

Lower your consumption

Here are tips to lower the consumption of processed meats, red meats and to lower carcinogen exposure:^4,5

• Vegetarian days – pick a day or days during the week to not eat red meat.
• Follow a healthy plate (See Figure 1).
• Substitute red meat for fish or chicken (without skin).
• Incorporate more legumes into your meals.
• Planning your meals a week in advance may help not to exceed the required limits.
• Try to use charcoal briquettes, as it burns at lower temperatures.
• Limit products that contain monosodium glutamate (MSG), high fructose corn syrup, artificial colouring and flavours.
• Marinated meats will produce less PAH and HCAs.
• Avoid flames from coming into direct contact with the meat.
• Remove the charred portions of the meat before eating.
• Remove excess visible fats before the braai, to prevent smoke and to control fat intake.

Final bite

Taking the bigger picture into account, red meat in moderation can still be incorporated into a balanced meal plan. Animal protein in moderation can definitely be your friend, when trying to fight the cancer battle or during cancer survivorship. All cancer patients have individualised requirements, as such it remains best to contact a registered dietitian for an individualised meal plan.

References:

1. World Cancer Research Fund and American Institute for Cancer Research. 2018. Meat, Fish and airy products and the risk pf cancer.
2. World Health Organisation. 2015. Cancer: Carcinogenicity of the consumption of red meat and processed meat. https://www.who.int/news-room/q-a-detail/cancer-carcinogenicity-of-the-consumption-of-red-meat-and-processed-meat [27 February 2021].
3. Knuppel, A., Papier, K., Appleby, PN., Key, TJ., Perez-Cornago. A. 2019. Meat intake and cancer risk: prospective analyses in UK biobank:73(1).
4. 2017. Fact Sheet On Dangers of Meats Cooked at High Temperature.
5. Cancer research UK. 2020. Does eating processed and red meat cause cancer?https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/diet-and-cancer/does-eating-processed-and-red-meat-cause-cancer#keyrefsmeat0 [27 February 2021].
6. Cancer research UK. 2020. What is a healthy plate?https://www.cancerresearchuk.org/about-cancer/causes-of-cancer/diet-and-cancer/what-is-a-healthy-diet [28 February 2021].