It's a well-known thing amongst doctors that heavy drinkers have a mysterious propensity for breaking their bones — and not just because they may trip over their own feet in an inebriated stupor. Medical researchers from Loyola University in Chicago wanted to get to the bottom of the issue, and they addressed the question the only way they saw fit: by getting mice drunk and breaking some bones.
Past studies have yielded some good guesses for this phenomenon: Brittle bones may simply be a result of the malnutrition associated with alcoholism, or that alcohol impedes the work of osteoblasts — the cells that help grow bones. In order to find out more, the Loyola team dosed mice with enough alcohol to yield a BAC of .20 in a human, well over the legal driving limit of .08 (it's .05 in Australia, mind you).
After an induced fracture, the boozy mice tibias didn't heal in the same way as that of the control group. The temporary mass of tissue formed between the broken bones, known as the callus, was much softer — a result of decreased levels of key protein osteopontin, which leads soon-to-be-osteoblast stem cells to the site of the fracture.
Mice who were given alcohol also showed higher numbers of a molecule that indicates oxidative stress, a finding that's in keeping with past studies. Alcohol consumption seems to increase production of dangerous oxidizing molecules that can't be broken down as easily by our bodies and, in turn, cause extra harm in the liver. Science has yet to explain how this specific piece of evidence impacts bone healing, but this new study confirms a connection, at the very least.
We're not entirely sure how turning mice into alcoholics may translate to the effect of alcohol on human bone growth. But I think it's safe to say that building up your tolerance isn't going to keep your bones intact, even if it may spare you a few embarrassing nights. [Smithsonian]