Beavers? Seriously?

Here’s a piece of news to chew on. A recent study of beavers’ teeth may lead to decay-resistant teeth for humans.

Although beavers never brush their teeth, and they certainly don’t drink fluoridated water, their teeth are protected from tooth decay by the iron that’s part of the tooth’s chemical structure.

If you looked at a beaver’s teeth, you’d notice that their iron-rich coating gives the teeth a reddish-brown or orange color. Apparently orange is the new white.

Researchers found that the pigmented enamel on beavers’ teeth is both harder and more resistant to acid than human tooth enamel, even when treated with fluoride. This discovery could lead to a better understanding of human tooth decay, as well as improvements in current fluoride treatment.

Tooth decay in humans is a major public health problem, even in this era of fluoride treatments. The American Dental Association estimates that dental care in this country costs $111 billion a year, and much of it is spent on cavities and other tooth-decay issues. According to the World Health Organization, up to 90 percent of children and nearly 100 percent of adults worldwide have or have had cavities.

The research team, led by Derk Joester, an engineering and materials science professor at Northwestern University, discovered that small amounts of an “amorphous solid” rich in iron and magnesium are what make rodent teeth resistant to acid. “[We’ve made a] big step forward in understanding the composition and structure of enamel—the tooth’s protective outer layer…,” said Joester.

Researchers included Jill D. Pasteris, a professor of earth and planetary sciences at Washington University in St. Louis. She calls their findings a great example of “the structural-chemical novelty [we’re] still discovering in natural, biomineralized materials” like teeth and bone.

Looking at the teeth of beavers and other rodents, the researchers used powerful technology to map the enamel’s structure, atom by atom. They subjected the teeth to acid and took images before and after. The journal Science published this unprecedented imaging study of tooth enamel in February.

Some of the details of the research are pretty technical, but you really should give a dam about the results. Although a beaver’s teeth are chemically different from our teeth, they’re not structurally different, and the results of the study may lead to stronger tooth enamel and better fluoride treatments.

This news is especially encouraging in light of what we’ve just learned about the sugar industry. The industry has for years covered up proof that reducing sugar-consumption prevents tooth decay. The San Francisco Examiner reports that researchers at UC San Francisco have found documents revealing how the industry worked with the National Institutes of Health (NIH) to avoid condemning sugar, trying instead to develop alternatives (like a vaccine to prevent tooth decay).

Buried in an archive of industry documents discovered at the University of Illinois was a startling document. It showed that a sugar-industry group acknowledged as early as 1950 that sugar causes tooth decay. But, according to the UCSF researchers, Dr. Cristin Kearns and Laura Schmidt, the sugar industry influenced NIH to steer scientists toward developing alternative approaches to tooth decay instead of focusing on the damage done by sugar consumption. (The study is published this month in the scientific journal PLOS Medicine.)

Does this remind you of the tobacco industry and its efforts to suppress scientific evidence that smoking leads to cancer and other illnesses?

The damage caused by sugar is finally getting attention from scientists, and efforts to cut back on its consumption are gaining ground. Last November, voters in Berkeley imposed a tax on sugary drinks, and a majority of San Francisco voters approved a soda tax (it didn’t become law because it required two-thirds to pass). [My blog post, “Gimme a Little Sugar,” published on 10/2/14, focuses on the damage done by sugary drinks and by sugar in general.]

Three SF supervisors have just renewed their efforts to restrict the consumption of sugary drinks in San Francisco. But even if efforts like these succeed, we’ll still face the problem of tooth decay for years to come. So paying attention to beavers’ teeth may prove helpful.

Let’s snatch victory from the jaws of tooth decay. If we start by Leaving it to Beavers, our descendants may someday sport decay-resistant teeth just like theirs.