Ancient Teeth Bacteria Record Disease Evolution 97
An anonymous reader writes "DNA preserved in calcified bacteria on the teeth of ancient human skeletons has shed light on the health consequences of the evolving diet and behavior from the Stone Age to the modern day. The ancient genetic record reveals the negative changes in oral bacteria brought about by the dietary shifts as humans became farmers, and later with the introduction of food manufacturing in the Industrial Revolution."
Re:humans (Score:5, Interesting)
...nice guess, but RTFA and learn a bit of actual dental hygiene. What you eat isn't the problem, it's what it attracts. With the exception of extremely acidic beverages, the food we eat does not directly damage our teeth. Getting lots of calcium is certainly important for preventing osteoporosis, in teeth and elsewhere, but that's the whole story. You can eat as much sugar as you want if you're in a completely sterile environment. It won't hurt you. (Not that such a place exists.)
Every exposed surface both inside and out of the human body is its own little bacterial world. The flora in the intestines have been in the news a lot lately because it's become apparent that some diabetes and obesity cases are tightly linked to disruptions in the compositions of these communities—the wrong bacteria get in and cause trouble.
The big discovery of the story is that the bacteria in the mouth used to be a lot more diverse. Just like the intestines of the obese, agriculture has put our mouths (with very few exceptions like the bushmen and uncontacted peoples) into bad shape. It's not natural for us to even need to brush our teeth—note no other animal doing this.
I also think you've misrepresented life expectancy a little by componentizing things... as well as being a tiny bit low numerically. The wealthy in ancient Greece averaged about 70 years, without anything resembling sanitation, and the average Roman commoner made it to 45. It's true that some components stop functioning earlier, but that doesn't mean Mother Nature would disapprove of us pushing past it. Many of the changes the occur in middle age can have positive outcomes [washingtonpost.com] on the social group by encouraging the individual to focus on other aspects of life, primarily looking after the family or tribe.
Re:But We're Living a Lot Longer (Score:5, Interesting)
1/ Small amounts of topical fluoride have a beneficial effect on teeth
2/ Large amounts of ingested fluoride weaken both your bones and teeth.
3/ Ingested fluoride accumulates in the body, mostly in the bones. 50% of what is ingested is never excreted.
4/ There is a slight correlation between water fluoridation and dental health.
5/ The possible benfits of water fluoridation are hard to quantiry because they are swamped by the effects of fluoride toothpaste
6/ There is at least as strong a correlation between water fluoridation and hip breakage in the elderly.
7/ Both sides are pushing an agenda, everything reads like propaganda unless you read the actual journal articles.