NO and the Mouth–Heart Connection
Mouthwash as a contributor to heart disease seems a bit far-fetched until the oral microbiome is included in the equation. That’s what we’ve learned. Just one week of chlorhexidine daily use in one study resulted in a more acidic oral environment and lower nitrite availability in healthy individuals. Even weaker strength mouthwashes have been observed to lead to lower saliva and plasma nitrite levels in healthy volunteers.
The oral microbiome is composed of a variety of microbes. Key species have been associated with not only good oral health, but with the ability to take nitrate from food and convert it to nitrites, which are then converted to nitric oxide (NO) further along in the digestive tract. Said a different way, specific strains of bacteria in the mouth take nitrate from the food we chew and begin the process of making a substance that enables good blood circulation, healthy blood pressure, and heart health. Nitric oxide not only benefits cardiovascular health, but also enhances athletic performance since it controls oxygen delivery, how oxygen is used in the mitochondria, and how well the mitochondria produce energy.
As you can imagine, the environment of the mouth is consistently fluctuating throughout the day depending on what enters the mouth in liquid or solid form. “The abundance of bacterial species can alter rapidly in response to alterations in environmental pH, carbohydrate availability, oxygen tension and the redox environment, and exposure to antimicrobials such as fluoride and mouthwashes.”[1] What we eat, when we eat, our oral health, exposure to antibiotics, fluoride, mouthwash, and even the amount of exercise we get can all affect the oral microbiome in good or bad ways.
Of particular interest to me was how a low-carbohydrate, high-fat diet affected the oral microbiome. Three groups of elite distance walkers adopted either the low-carb, high-fat diet or two other diets that contained carbohydrates for three weeks. Those on the low-carb, high-fat diet not only failed to improve their race performance compared with the other two groups, but also experienced a decrease of beneficial bacterial strains in their mouth and an increase of streptococcus bacteria (that are not so beneficial).[2] This shift in the oral microbiome could ultimately result in decreased NO and potentially be one of the reasons for the underperformance. It also provides one explanation for why a whole-food plant-based diet could be more favorable to a healthy mouth environment.
The topic of nitrates provides another variable that highlights how a whole-food plant-based diet would be superior for oral health. Nitrates are the substrate oral bacteria use to begin NO production.
But wait a minute. Aren’t nitrates the preservative put on processed meat to keep it uncontaminated and safe to eat?
Yes.
Does that mean that all the hype about nitrates being carcinogenic is no longer valid?
I found the following information helpful in nuancing this topic: There are forms of nitrate used to preserve meat and provide flavor and color enhancement are potassium nitrate or sodium nitrite. These forms of nitrate “have been suggested to increase the risk of carcinogenesis, possibly to due to the formation of nitrosamines following ingestion.”[3]
On the other hand, vegetables don’t make nitrosamines because they are loaded with antioxidant nutrients. And the best source of nitrates are vegetables; green leafy vegetables, beets, lettuce, etc.
After Adam and Eve left the garden of Eden, God provided different foods that had the capacity to support, restore, revitalize, and recharge the human body in exceptional ways. All we gotta do is eat them.
[1] Murtaza, Nida et al. “Analysis of the Effects of Dietary Pattern on the Oral Microbiome of Elite Endurance Athletes.” Nutrients vol. 11,3 614. 13 Mar. 2019. https://doi.org/10.3390/nu11030614
2 Bryan, N. S., Burleigh, M. C., & Easton, C. (2022). The Oral Microbiome, Nitric Oxide and Exercise Performance. Nitric Oxide, 125–126. https://doi.org/10.1016/j.niox.2022.05.004
3 Ibid.