Using mouthwash that kills mouth bacteria might be bad for heart health because it raises blood pressure by disrupting the body's natural nitrite balance.

When people start using mouthwash that kills mouth bacteria, their blood pressure can go up within just one day.

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.

Using a special mouthwash for a week killed some good bacteria in the mouth, which made less nitrite in saliva and blood, and this caused blood pressure to go up a little bit.

When people used the special mouthwash, their blood pressure went up within one day and stayed higher for the whole week they used it.

Using mouthwash that kills mouth bacteria leads to higher levels of nitrate in both saliva and blood.