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Sugar, acid and teeth (2009)

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Re: Sugar, acid and teeth (2009)

#21

Post by scott_s »

bmelton wrote: post #11
casca wrote: post #5

Interesting, but their choice of weighting of sugar and pH is not based on any evidence. Also, would the amount of time that the drink is in contact with your teeth not have an impact? Perhaps wine would have more of an impact because you might keep it in your mouth longer, offset by the small likelihood you you drinking as much of it?

Similarly, I read something recently (no link, sorry) that stated something like the following (poorly paraphrased): Juice is fine to drink as it's generally healthy, but if you're going to drink it, do so quickly instead of sipping on it for long periods. The premise being exactly what you surmised, that chugging a small glass of OJ is much better for your teeth than sipping it and putting your teeth into contact wi…

It may be better for your teeth, but I wonder if chugging it will spike your insulin more.

Re: Sugar, acid and teeth (2009)

#22

Post by SoftwareMaven »

cmatteri wrote: post #13
jws wrote: post #2

Where "worst" is defined by a function of pH and sugar content pulled out of the air by a dentist.

Their function 10^(5.5-pH) * (mg/cl sugar + 1) does seem to imply that sugar and acidity have a synergistic effect, where the +1 in the sugar term is a hack to keep the result from being 0 if the sugar is 0. This doesn't make sense, as a modest increase in sugar, say from 0 to 1 would double the result regardless of the pH.

What the equation says to me is that acidity sets the stage for tooth damage, but as bad as that is, once you start feeding the bacteria in that set stage, you are in real trouble.

However, the entire article is a hypothesis. It is a best guess by somebody with scientific knowledge, but there is no reason to believe the real formula shouldn't be 10^(5.5-ph)+10(mg/cl sugar) or something completely different.

However, my son and daughter both need a science fair project soon. I wonder if there is a way to formalize this a little.

Re: Sugar, acid and teeth (2009)

#23

Post by bmelton »

scott_s wrote: post #21
bmelton wrote: post #11

Earlier quoted context omitted.

Similarly, I read something recently (no link, sorry) that stated something like the following (poorly paraphrased): Juice is fine to drink as it's generally healthy, but if you're going to drink it, do so quickly instead of sipping on it for long periods. The premise being exactly what you surmised, that chugging a small glass of OJ is much better for your teeth than sipping it and putting your teeth into contact wi…

It may be better for your teeth, but I wonder if chugging it will spike your insulin more.

That was kind of the same question I had when I read it, but I came to the (completely uninformed) conclusion that probably, the body's absorption rate was self-metering enough that it probably wouldn't make a difference drinking it all at once vs. drinking it over a 20 minute period.

I have absolutely no evidence whatsoever to support this however, so who knows?

Re: Sugar, acid and teeth (2009)

#24

Post by squarecat »

jws wrote: post #2

Where "worst" is defined by a function of pH and sugar content pulled out of the air by a dentist.

Seems having only a dentist on hand for that "experiment" is akin to having a mechanic as your only expert for analyzing a car wreck? As the author even concedes, an abundance of anecdotes is not evidence.

Was it so hard to find a chemist way back in aught-9? (Go down to the nearest uni and find a chem major at least...)

The wide distribution of oversimplified, media-sanitized, pseudo-science is likely one of the affectations of Western culture that has kept it from progressing further for a solid 60 years--since television gave the ability for snake oil salesmen to multiply their effectiveness. The internet exponentially increased that ability.

Re: Sugar, acid and teeth (2009)

#25

Post by Royal »

cmatteri wrote: post #13
jws wrote: post #2

Where "worst" is defined by a function of pH and sugar content pulled out of the air by a dentist.

Their function 10^(5.5-pH) * (mg/cl sugar + 1) does seem to imply that sugar and acidity have a synergistic effect, where the +1 in the sugar term is a hack to keep the result from being 0 if the sugar is 0. This doesn't make sense, as a modest increase in sugar, say from 0 to 1 would double the result regardless of the pH.

Their function also improves the results if the drink is more basic. A drink with a pH of 13 would have an amazing score on here.

If you normalize the pH above 5.5 since it has "little to no effect" things on the lower end of the results are better, with milk being worse than water, and chocolate milk being worse than milk.

Re: Sugar, acid and teeth (2009)

#26

Post by xaa »

SoftwareMaven wrote: post #22
cmatteri wrote: post #13

Earlier quoted context omitted.

Their function 10^(5.5-pH) * (mg/cl sugar + 1) does seem to imply that sugar and acidity have a synergistic effect, where the +1 in the sugar term is a hack to keep the result from being 0 if the sugar is 0. This doesn't make sense, as a modest increase in sugar, say from 0 to 1 would double the result regardless of the pH.

What the equation says to me is that acidity sets the stage for tooth damage, but as bad as that is, once you start feeding the bacteria in that set stage, you are in real trouble. However, the entire article is a hypothesis . It is a best guess by somebody with scientific knowledge, but there is no reason to believe the real formula shouldn't be 10^(5.5-ph)+10(mg/cl sugar) or something completely different. However,…

How about the following:

1. Find a substance that is chemically tooth-like

2. Split it into predefined volumes (little cubes or spheres)

3. Add the beverage and saliva to the "tooth", wait a month, and measure the decrease in "tooth" volume.

4. Use regression to estimate the coefficients for sugar, pH, and whatever else.

Re: Sugar, acid and teeth (2009)

#27

Post by Alex3917 »

nealabq wrote: post #9

One hears that Bulimia and certain drug addictions (Crack, Meth) are very bad for your teeth. Bulimia because of the strong acid, and drugs because they interfere with the mouth's self-cleaning instinct. I'd guess the best teeth live in a mouth with: 1. Active high-volume saliva glands 2. A population of healthy bacteria How do you encourage that?

The reason why amphetamines are bad for your teeth is that they prevent your mouth from making saliva, which allows bacteria to multiply and causes other bad things to happen as well. Obviously it's probably not a good idea to be using meth in the first place, but if you're going to use any sort of drug that causes dry mouth then at the very least you should brush, floss, and use mouthwash and flouride rinse beforehand.

Re: Sugar, acid and teeth (2009)

#28

Post by deltaqueue »

I wish he would have provided more explanation behind the dentist's algorithm. Here's an actual study measuring enamel loss, which seems much more definitive:

http://faculty.philau.edu/ashleyj/General%20Dentistry%20Arti...

Perhaps the most important snippet:

Regression analysis indicated no correlation between enamel dissolution and beverage pH (r = 0.477, p > 0.05); in addition, the enamel dissolution showed no difference (p > 0.05) between the regular and diet versions of cola and non-cola beverages from the same manufacturer (Fig. 2 and 3). It was noted that the enamel dissolution was similar for all cola drinks over the 14-day test period (approximately 3.0 mg/cm2).

And again:

The data suggest that enamel aggressivity is determined by beverage composition rather than by beverage pH.

Re: Sugar, acid and teeth (2009)

#29

Post by steve8918 »

peterwwillis wrote: post #18
steve8918 wrote: post #15

I have deep grooves in my teeth right above my gums on both sides of my mouth from drinking 3-6 cokes a day for 10+ years. For some reason, I have a habit of swishing the drinks on the bottom of my mouth and I think this is the reason why my teeth are so jacked up. In the past year, I've largely stopped drinking Coke, partly because of this, and because of the other health problems associated with drinking so much so…

Besides being bad for your teeth it's a nightmare on your body. That insulin dump from the onslaught of sugar will make you much more likely to develop diabetes, and some studies have shown a long-term metabolic effect where your body prefers sugars for energy instead of fats. That and the empty calories will lop-side your diet and make it harder to lose weight or gain muscle. There are lots of ways you can drink som…

I 100% agree. Actually I have done almost exactly that, switched to tea, or ice tea. I'm not completely off the sugary drinks, but I'll drink things like Honest Tea with a lot less sugar than Coke, or just plain Tea.

The thing I'm actually most worried about is pancreatic cancer. I'm not even sure if there's a link between that and soft drinks, but I read one study where having 2-3 soft drinks a week doubled your risk of getting it. Well I was having 20 a week, which scared the crap out of me. And more and more people appear to be contracting and dying of it, so it's my secret fear.

Re: Sugar, acid and teeth (2009)

#30

Post by TillE »

peterwwillis wrote: post #18
steve8918 wrote: post #15

I have deep grooves in my teeth right above my gums on both sides of my mouth from drinking 3-6 cokes a day for 10+ years. For some reason, I have a habit of swishing the drinks on the bottom of my mouth and I think this is the reason why my teeth are so jacked up. In the past year, I've largely stopped drinking Coke, partly because of this, and because of the other health problems associated with drinking so much so…

Besides being bad for your teeth it's a nightmare on your body. That insulin dump from the onslaught of sugar will make you much more likely to develop diabetes, and some studies have shown a long-term metabolic effect where your body prefers sugars for energy instead of fats. That and the empty calories will lop-side your diet and make it harder to lose weight or gain muscle. There are lots of ways you can drink som…

Unsweetened tea and coffee are definitely your best bets next to plain tap water for generally healthy drinks. Though I have found that drinking loads of black tea stains your teeth (it was cleanable), and switched to green tea.

http://www.hsph.harvard.edu/nutritionsource/healthy-drinks/

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