Researchers from the SIT have revealed the mechanism by which the bitter taste of plant-based polyphenols interacts with T2R in the gut to secrete GI hormones. This regulates blood sugar levels and appetite, and reduces the risk of diabetes and obesity.

Bioactive compounds such as polyphenols and their associated health benefits have long been of great interest to the public. These compounds are commonly found in plant-based foods such as fruits, vegetables, seeds, coffee, and tea. Polyphenols have a strong bitter taste and are typically poorly absorbed by the body, leading to their excretion.

The polyphenols interact with human bitter taste receptors, also known as Type 2 taste receptors (T2R), which are expressed within and outside the oral cavity. Importantly, the activation of T2R expressed along the gastrointestinal (GI) tract is responsible for the bioactivity of ingested polyphenols. The scientific mechanisms behind T2R activation, which lead to the reported health benefits of polyphenols, are still unclear. With over 8,000 types of polyphenols and 25 types of human T2R, this represents a crucial gap in knowledge.

“Professor Osakabe has stated, ‘Although polyphenols are poorly absorbed, there are reports indicating that they can enhance glucose tolerance. We are currently researching the correlation between polyphenol consumption and the risk of type II diabetes, as the exact mechanism behind this positive effect remains unidentified.'”

“The gastrointestinal hormones regulate feeding behavior and maintain glucose tolerance through the endocrine and nervous systems. Therefore, it is possible that the bitter taste of polyphenols helps to reduce the risk of diabetes and its complications by activating T2R.”