Blood type A sugars fuel gut microbes and keep you healthy

Sugars from type A blood as energy source

The human intestine is home to trillions of bacteria and other microbes that need different types of carbohydrates for energy. It used to be thought that they got these carbohydrates mainly from our food. However, the new work by Fu and Harmsen reveals that some gut microbes can also use sugars belonging to our blood group that are exported into our gut mucus as a source of energy.

The researchers discovered this by exploring a strong link between the human genetic variation ABO and a specific genetic block in a key gut microbe called Faecalibacterium. ABO genes determines our blood type, and each blood type has its own type of sugar. The researchers could show that the genetic segment present in Faecalibacterium linked to having type A blood contains a specific sugar pathway that allows it to use type A blood sugar as an energy source. 'This shows that our genetic makeup determines which bacteria we have in our intestines,' says Harmsen.

Contribution to better health

When bacteria use type A blood sugar, it leads to a healthier and more diverse community of gut microbes, the researchers found. This contributes to better heart and vascular health and metabolism in people with type A blood. Fu: 'Microbiome therapy, such as poop transplantation, is a good method for disease prevention and treatment. Our research suggests that treatment is likely to be more effective if we match the genetics of the microbiome to the patient's genes.'

'Now that we know that our genetic makeup itself determines which bacteria are in our gut, this seems to help explain variations we see in how people respond to nutrition and therapy,' Harmsen adds. 'What is good for people with blood group A may not be good for people with blood group B or O.'

Read the full publication here.