I got a little excited when I ran across this scientific article. My hopes were quickly deflated and I’ll tell you why shortly.
In 2007, 10 study subjects did a Stone Age reenactment over the course of four weeks. It was covered extensively by Swiss TV.
Dental plaque is a complex biofilm that accumulates on teeth and oral tissue. It’s influenced by diet and genetics. Plaque can lead to gingivitis (gum inflammation and disease). If untreated, gingivitis can lead to the more serious periodontitis with tooth loss. A couple human studies in the 1980s showed that a high-carbohydrate diet leads to gingivitis, compared to a low-carb diet. Dietary sucrose (table sugar) is linked to increased plaque and gingivitis.
The Experiment: Swiss Stone Age Lifestyle
The ten subjects included two families of four plus two young men. Four were children or adolescents. Anthropologists created an environment replicating living conditions close to the Rhine River between 4000 and 3500 BC. “Living quarters, clothing , tools, and types of food stock were provided as known from archeological findings in the region. Therefore, the diet was restricted to included a basic supply of whole grains of barley, wheat, spelt (“einkorn,” “emmer” = local ancient agricultural wheat), some salt, herbs, honey, milk, and meat from domestic animals (goats and hens). A hunter would shoot one of the goats at the participants request….(T)hey were forced to seek supplemental food from nature, including berries, edible plants, and fish without nets.” Subjects had no access to toothbrushes, toothpaste, tooth picks, or floss. Oral hygiene was assessed before and after the four weeks in this environment. We don’t have a nutritional analysis of individuals’ dietary habits during the experiment. “Cereals and berries were primary food sources for the subjects.”
Some of you have already noted the source of my disappointment. The paleo diet most of us talk about today in the U.S. provides no wheat or milk, or at least very little. The anthropologists considered this set-up early Stone age, but wasn’t it more late Stone Age or Neolithic?
What Did They Find?
Gum bleeding-on-probing and probing depth decreased (potentially healthy trends). Plaque index increased (more plaque, but they had no increase in severity of gingival inflammation). Gingival index (not defined in the paper) didn’t change. Bacteria growing on the teeth and gums changed, but I won’t bore you with the details.
The investigators surmise that subjects avoided an increase in gingival inflammation due to table sugar restriction and intake of foods rich in anti-inflammatory and antibacterial components.
The researchers conclusions:
The experimental gingivitis protocol is not applicable if the diet (e.g., Stone Age) does not include refined sugars. Although plaque levels increased, bleeding-on-probing and plaque index decreased. Subgingival bacterial counts increased for several species not linked to periodontitis whereas tongue bacterial samples decreased during the study period.
Bottom Line for Me
I’m not aware of other paleo bloggers covering this study, and I can see why. It’s a small short-term experiment. The inclusion of grains and milk in the experimental protocol limits its applicability to the currently trendy paleo diet.
While I mostly wasted a couple hours on this, I hope I saved you the effort. You’re welcome.
In the comment section, feel free to share your dental effects when you switched to a paleo diet.
Reference: Baumgartner, Stefan, et al. The impact of the Stone Age diet on gingival conditions in the absence of oral hygiene. Journal of Periodontology, 2009 (80): 759-768.