Many protein-rich foods contain the essential amino acid tryptophan. Scientists at the University of Colorado have discovered that it is converted by bacteria in the digestive tract in a way that promotes inflammation and contributes to the development of arthritis. The study was published in the Journal of Clinical Investigation.
Tryptophan is found in many protein-rich foods: meat, fish, dairy products, some seeds and nuts. It cannot be produced by the body itself, but is absorbed through food. An essential amino acid performs many functions in the body, including supporting the development of proteins, muscles, enzymes and neurotransmitters, substances that mediate the nervous system.
It is known that the microbiome – the bacteria in our intestines – can break down tryptophan into byproducts . Some of these byproducts have anti-inflammatory effects, but some inflammatory effects of these products have also been found.
Scientists looked at people with spondyloarthritis, which affects the spine and joints. In this disease, changes in intestinal flora have been found to be associated with increased production of the byproduct indole. It is produced by bacteria from tryptophan.
Scientists say a Mediterranean diet, rich in plant fiber and lean meat, promotes a healthier state of intestinal flora while maintaining tryptophan's anti-inflammatory properties.