Health

Gut bacteria generate compounds from vegetables linked to health benefits

Researchers found that gut microbes convert dietary nitrate and iron into dinitrosyl iron complexes, which improved health markers in animal models.

Updated Aug 24, 2026 · 14:19 UTC1 reports

The short version

Researchers at Karolinska Institutet discovered that gut bacteria combine nitrate and non-haem iron from foods to form dinitrosyl iron complexes (DNICs).
In animal models, higher levels of DNICs were associated with lower blood pressure, improved blood sugar control, better vascular function, and reduced liver fat.
Researchers plan to develop ways to measure DNIC levels in humans and determine if dietary changes can leverage this mechanism to help prevent disease.

A study published in Cell demonstrates that gut microbes convert dietary nitrate and plant-based non-haem iron into dinitrosyl iron complexes (DNICs).[ScienceDaily]
DNIC molecules were completely absent in germ-free mice, indicating that gut microbes are necessary for their production.[ScienceDaily]
Once formed, DNICs can be absorbed and transported to organs such as the liver and kidneys.[ScienceDaily]
Increasing DNIC levels in animal models of cardiovascular and metabolic disease yielded improvements in blood pressure, vascular function, blood sugar control, and liver fat levels.[ScienceDaily]
The research was led by Karolinska Institutet in collaboration with the University Medical Centre Hamburg-Eppendorf and Johannes Gutenberg University Medical Centre Mainz.[ScienceDaily]

Because much of the research was conducted in experimental animal models, cells, and bacteria, additional studies are required to confirm how the process functions in humans.[ScienceDaily]
It remains unknown whether dietary adjustments or gut microbiota modifications can effectively alter human DNIC levels to prevent disease.[ScienceDaily]