This recent study in the journal Nutrition talks about the association between processed meat consumption and the risk of developing breast cancer. As well as other hormone-related cancers.

Previous research had shown an increased risk of bowel cancer among those who ate more processed meats. But this study also found that women who consumed more processed meat were more likely to get hormone-related cancers. Hormone-related cancers in women include breast, ovarian and endometrial cancer.

In addition, these foods may be linked to cancers in other parts of the body, such as the stomach, oesophagus and lung.

What are processed meats?

Processed meats have undergone some kind of processing to improve the product’s shelf-life, colour or flavour. 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:

• bacon
• boiled and cured ham and luncheon meats
• hot dogs, frankfurters, sausages and salami
• tinned meats such as spam and corned beef

What makes these foods unhealthy?

Suggested reasons for the health risks attributed to these foods 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 animal products 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.

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 these foods.

Researchers compared the intake of processed meats with the incidence of breast cancer and other hormone-related cancers. They say a higher intake is 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 a higher intake of meat, because of the level of sex hormones found in these foods. 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.