We’ve been using baking soda (also called bicarbonate soda, a base) to brush our teeth for the past 2 months (I mix table salt with baking soda in equal parts and a bit of tea tree oil for flavor). We also floss daily and so far I’ve haven’t noticed any change in our teeth or gums (bleeding, sensitivity, or formation of cavities). I started using baking soda because I wanted to eliminate the plastic packaging that comes with tooth paste. My decision to use baking soda to brush my teeth has nothing to do with fluoride that is often found in toothpaste which is apparently a touchy subject for some people.

I decided to read more about the use of baking soda and its effects on oral care and whether it was actually a good idea to use it for oral care. I also wanted to see what flouride actually did to one’s teeth.  

Our teeth are constantly undergoing remineralization and demineralization based on what we eat.  Fluoride serves to protect our teeth enamel which can decay quickly if exposed to too many acidy foods (lemons, vinegar, tomatoes etc)[1]. Additionally, our mouth is naturally a bit acidic and saliva is a base that neutralizes it. Most people in the US drink water that contains fluoride whether they want it or not. You can check here to see how much fluoride is in your water supply. After reading about fluoride, I think the fear of fluoride comes from the fact that too much can be poisonous. Here is a paper stating some facts about fluoride, including how much is necessary at various ages. For adults the amount required is between 3.0 to 4.0 mg per day.

So essentially good oral care means ensuring that the teeth enamel is not exposed to too many acids because it would break down the enamel which will cause pain and expensive dental bills. So using baking soda to brush my teeth means that I’m using a base to neutralize the acidity in my mouth. Thus, baking soda does not harm one’s teeth. 

I know that the poor in my home country use wood ash to brush their teeth. I’ll bet that wood ash also serves to neutralize the acids in our mouth. So using wood ash is super eco-friendly for those with access to a wood stove.

Hmm…it just occured to me that we could use wood ash to decrease the acidity in our composter instead of buying garden lime.  

EDIT: Husband has a chem degree so he had this to add:

F2 (Pure Flourine) is the most reactive gas known to man. It will corrode nearly all metals, etch glass, and cause paper to burn upon mere exposure at room temp.

F-, however is an ion that can only be found in water solution and will kill bacteria that cause tooth decay, but is not known to harm a human in any way.
Note, F2 is similar to Cl2 (Chlorine) in properties. Cl2 was used in WW I was a chemical weapon. It is now banned.
Cl- is an ion that is critical to life. If you got rid of all Cl- in your body you would die instantly.

Basing any opinion of an element based on what that element can do in a much different environment is not science. It makes no sense in anyway except for a dream like associative way.

But, you know, people would rather eat food with a small amount of toxins in it rather than hear a chemistry lecture…

[1] One method we use to check our food content’s acid level is by watching our worms. If our worms turn white we know we’re composting too much acid based foods. You can also just try the PH paper method to figure out acidity levels, but worms are so much more fun.