Bovine Milk Proteins as a Trigger for Autoimmune Diseases: Myth or Reality?

Humans started to drinkmammal’s milk 11,000 years ago. Nowadays, cow, goat and sheep milks account for about 87% of the world milk production. The high incidence of allergies to cow’s milk components and autoimmune diseases is rising in the Western industrialized countries, where milk is a major dietary component, especially in processed foods. When allergenic milk proteins face immature and susceptible immune system in children it might represent a threat for future health. Several studies support strong evidences that exposure to dietary allergens during childhood can increase the risk of developing autoimmune diseases, such as type 1 diabetes, celiac disease, inflammatory bowel disease, rheumatoid arthritis, multiple sclerosis, neuropsychiatric disorders, among others. The "Mosaic of Autoimmunity" elucidates the diversity and multifactorial origin of autoimmune disease expression in humans. Growing evidence suggests a large overlap between oral tolerance, food antigens and autoimmune diseases. Assorted mechanisms have been hypothesized to explain the connection between these entities, mainly involving molecular mimicry, shared epitopes, cross-reactivity phenomena, enhanced hosts gut permeability, change in microbiome/ dysbiome ratio and even involving Mycobacterium avium subspecies paratuberculosis infection. Nowadays, different kinds of milk and dairy products are being evaluated for a potential benefit in human health. Likewise, milk derived nutraceutical products, such as bovine colostrum, claim many clinical advantages especially for its immune modulatory capabilities. The aim of this review is to explore the impact of cow’s milk protein son human health, emphasizing its relationship with immune mediated and autoimmune diseases.