The journal Nutrition recently published a study on the effect of eating processed meat with respect to the risk of developing breast cancer and other hormone-related cancers.
We know from previous studies that eating more processed meat is associated with a higher risk of developing bowel cancer. Plus, these foods may be linked to cancers in other parts of the body, such as the stomach, oesophagus and lung. This new study focused on the hormone-related cancers of the breast, ovary, endometrium and prostate.
What are processed meats?
Processed meats are meat products that have been treated or modified to improve the shelf-life, colour or flavour of the product. Processing methods could involve curing, smoking or salting. Simple mincing or grinding of meat does not make this a processed food unless the meat then undergoes further treatment.
Some examples of processed meats:
- boiled and cured ham and luncheon meats
- hot dogs, frankfurters, sausages and salami
- tinned meats such as spam and corned beef
What makes processed meats unhealthy?
Suggested reasons for the health risks attributed to processed meats include their high content of fat, salt or heme iron. Food additives in processed meats such as nitrates and nitrites may also pose a risk.
Some cooking methods can increase the number of toxic compounds in foods. Polycyclic aromatic hydrocarbons and heterocyclic aromatic amines are toxic compounds that are formed during the cooking of meat at high temperatures.
Processed meats contain cancer-causing n-nitroso compounds. These carcinogenic compounds are also formed in the body after eating foods that contain nitrates and nitrites, such as processed meats.
How much processed meat?
In this study, the overall average consumption of processed meat was around 100g per week. However, some people, around 4 to 5% of those in the study, ate at least 50g per day of processed meats.
Researchers compared the intake of processed meats with the incidence of breast cancer and other hormone-related cancers. What they found was that higher intake of processed meats was moderately associated with a greater risk of developing breast cancer, endometrial cancer or ovarian cancer. However, a higher intake of processed meat was not associated with an increased risk of prostate cancer in this study.
The researchers also suggested that the higher risk of hormone-related cancers may be due to higher intake of meat, because of the level of sex hormones found in meat and meat products. In comparison they said, the Mediterranean diet and plant-based diets may protect against hormone-related cancers due to the lower levels of processed meat.