Fermented milks and cancer

Abstract

Cancer is a pathology increasing globally, and even when there are many new therapies being applied for different cancers, it is still an important cause of death, especially associated with metastasis. In addition, cancer chemotherapies are prolonged in time and many secondary effects can be associated to them affecting the quality of life of the patients. Many patients decide to consume foods that can offer some benefits on their health such as traditional or novel fermented products that contain beneficial microorganisms. Lactic acid bacteria (LAB) are present in the diet of many people worldwide and some of these can be claimed to be probiotics because they can confer proven health benefits on the host (FAO/WHO, 2001). Fermented milks are the most common fermented foods preferred as a source of beneficial microorganisms in the Western world; and they have been growing in popularity due to studies proving that some of them present health-promoting properties, among them the prevention or the complement of treatment for some types of cancers. Experimental animal models are used to study the mechanisms by which these fermented products can exert beneficial effects against cancer development. However, the evaluation in human trials is necessary to guarantee the application of dietary modifications in patients suffering cancer. Epidemiological studies also help to understand the positive or negative association between the consumption of dairy products and the risk of certain type of cancers. This chapter summarizes relevant researches about milk and dairy products (especially fermented milks) and their relationship with cancer during the last years. The analysis of fermented products containing probiotic microorganisms in cancer prevention and/or treatment will be discussed separately with emphasis in the possible mechanisms involved.