Sugar and Cavities - What is the relationship between the two?

How do we know that proper diet is important cavity prevention strategy? There’s lot’s of evidence we can review but let’s first start with some basics on how cavities form to begin with.

There are microscopic bugs in your mouth called bacteria and some of these bacteria may eat the sugars that you eat. From those sugars they produce acid, the acid dissolves the first layer of the tooth called enamel. Once it has dissolved the tooth through the first layer and get’s to the second layer, a hole is created that’s technically called a cavitated lesion or commonly referred to as a cavity. Now, there is a whole going one here but let’s focus on the sugar part of it.

If there is no sugar for the bacteria to eat, they can’t make acid, with no acid the tooth can’t dissolve so no cavity. A plus is that with no sugar for the bacteria to eat, they starve to death – an added bonus.

So, no sugar = no cavities!
And less frequent Sugar intake = less cavities.

Let’s look at some fascinating data from real life:

Greenland and traditional Inuit diet according to Google consisted of this:
Traditional Greenlandic food, rooted in hunting and fishing, features a protein-rich diet based on marine mammals, birds, and fish such as seal, whale, reindeer, and musk ox, alongside various Arctic fish and seafood like cod and shrimp. Key dishes include Suaasat, a thick, national soup made from seal meat, and mattak, a delicacy of raw whale skin and blubber. Other traditional foods involve methods like drying, smoking, and fermentation, with modern influences introducing imported goods and European-style dishes.

I don’t know about you, but after eating this all my life because importation of western or European foods high in carbohydrates and sugars was not possible:

I would be ready for something like this:
And they were. From 1901 when only 17% of the food was imported into Greenland to 63% in 1930 and, in some areas of Greenland, reached over 90%. The average sugar consumption per person per year increased from 11lbs in 1901 to 87 lbs 1930 – surpassing the amount of the United States and Denmark.

What happened to the decay rate (number of cavities) during this time? Cavities increased from 0% to 40% overall by 1935. But the cavity formation was not evenly distributed. The more remote traditional hunter gather’s and those living in harder to reach east coast (white on map) had significantly less decay then those living in the urban west coast (dark red on map) with the most access to western carbohydrate diet.

Hawaii. In 1778 Captain James Cook was the first recorded European to make contact with the Polynesians in the Island chain. Until this time they, like the Greenlanders, relied on the sea for much of their sustenance. However, they did have some native fruits such as Hawaiian gooseberry, Breadfruit and Mountain apple with the corresponding relatively small amount of sugars.

So, what was their cavity experience? No bad, when primary teeth where examined from skulls of children it was determined that there was detected in 10% of them. It is now 71% . There is a lesson here and that is that non-added sugar such as in fruits does not seem to make an overwhelming impact in decay, although it does some War time rationing in Britian children resulted in a decrease of 40% WW I and 30% n WW II.

Knowing that there are minimal cavities in societies that did not have access to an abundant supply of sugars and also observing that there are less cavities formed in areas that had a disruption in sugar supply or rationing led to the Vipeholm study. This well designed and executed study was carried out at a mental institution in Sweden. Consisted of dividing the patients up in to different groups and feeding various amounts and types of sweets along with varying the frequency of consumption. All done without consent of the patients as their mental state would not allow them to give it. The study was done, according to the investigators, because: “Long term studies on human beings seem to be the only method of capable of answering the question of causal relationship between carbohydrate intake and dental caries”.

Conclusions from the authors: The risk of sugar causing cavities increases if consumed between regular meals and given in a form that is sticky and retained on the service of the teeth. These results are highly variable from person to person.

How frequently between meals? Not all that frequent, 9:30 and 10:30 am and 1:30 and 2:30pm. A total of 4 times in addition to regular meals. This is very little compared to a child that has constant access to carbohydrate rich snacks.

Why are results highly variable? Likely because of the lack of cavity promoting bacteria present in some of the test subjects. Remember, it takes two things to get cavities the bacteria and the sugar for them to eat. One without the other will not produce decay.

Bottom line take home lesson: If you have cavities you have the bacteria that causes them and one will likely have to take their diet and frequency of carbohydrate intake very seriously in order to get it under control.