Your mouth has good bacteria that turn nitrate from food into nitrite, and this process works differently in men and women, which might affect how well their blood vessels work.

When people take a supplement called inorganic nitrate, women’s bodies turn more of it into nitrite than men’s do — so women end up with higher levels of nitrite in their blood.

Women tend to have more nitrite in their bodies than men when they're at rest, even though both have similar levels of nitrate—this suggests their bodies might process these chemicals differently just by being male or female.

Bacteria in the mouth help keep nitrite levels in the blood stable, which is shown by the fact that people with higher nitrite in their saliva also tend to have higher nitrite in their blood.

When you eat foods with natural nitrates, like spinach or beets, bacteria in your mouth turn them into nitrite, which then travels through your blood and becomes nitric oxide—a molecule that helps your blood vessels relax.

Using mouthwash that kills bacteria in the mouth makes it harder for the body to convert nitrate to nitrite, which lowers nitrite levels in the blood.