YES! That’s right! Forget clean eating! You can now eat nothing but cake and hotdogs and still lose weight! How amazing!….Sorry to disappoint, but that is not what my post is about today. During my travels in Ecuador, I got to see wild parrots at Yasuni National Park taking part in one of their favorite activities: clay licks or salt licks. This behavior is also seen in parrots in other areas: Why do hundreds of Macaws gather at these Peruvian clay banks? From what I was able to find online, there is still quite a bit of debate surrounding the benefits and detriments of eating dirt, also known as geophagy. For avian species, one main hypothesis is that the clay can help remove toxins from the body by binding to the toxins before they reach the gastrointestinal tract, thereby allowing the toxins to be eliminated from the body before full absorption. One study showed that clay will not only bind to toxins to help eliminate them from the animal’s body but will also stimulate the body to produce a type of mucus shield in the gut. Another theory is that the birds consume the clay as a sodium supplement. Apparently, areas deep in the Amazon are particularly deficient in sodium, a mineral that is vital for survival. This phenomenon occurs because the further away a location is from the ocean, the less salt remains in the rain, leaving animals to search for their sodium fix in other ways. Evidently, the parrots are also able to single out the specific layers of clay that are higher in sodium.
Parrots at Yasuni National Park carving out their minerals
Maybe you are thinking, “Wow, birds are weird.” You would be correct. They are quite a fascinating group (or flock, I guess), but geophagy is seen in other animals as well, including humans. This recent article by BBC, The People Who Can’t Stop Eating Dirt, was an eye-opener for me. In several African countries, finding earth intended for human consumption is common. The potential health benefits behind humans eating clay seem to be similar to the reasons non-human animals consume clay, such as gastric distress, eliminating toxins, or making up for mineral deficiencies. However, for humans, culture can also come into play. Geophagy seems to be especially popular among people suffering from anemia and/or pregnant women. This may be due to the fact that their immune systems are weaker and require extra nutrients to safeguard against pathogens. The strong drive to eat mineral-rich clay during pregnancy is also seen in bats. The BBC article also mentions that geophagy is commonly seen in elephants, cattle, and non-human primates.
Before you go outside and start licking your garden bed, remember that “not all dirt is created equal” and that geophagy can be addictive (yes, it’s true!). I think that there was another important point to consider in the BBC article: “Clearly there are downsides to consuming dirt. The presence of soil-borne diseases and toxic substances in the clay is a major issue, as is the possibility that the very deficiencies supposedly cured by the practice might even be caused by them.” This topic clearly merits more research, but it appears that adding some dirt to your diet may not be as crazy as it sounds. To wrap up, I leave you with a short Nat Geo video about parrot clay licks. Have a great weekend!