Fast Food Scraps Are Giving City Birds High Cholesterol

It's no secret that fast food is unhealthy and that may be true for more than just humans. A new study has found that crows located in urban environments are suffering from high cholesterol as a direct consequence of fast food consumption, mirroring the same health condition observed in many humans who frequently eat this high-fat convenience food.

Fast food can be found on the roads and parking lots of big cities around the world. These scraps of fast food are often targeted by scavenger animals, the most pervasive in urban environments being crows. These animals, according to the new study, have higher concentrations of cholesterol in the blood than crows located in rural areas.

The research comes out of Hamilton College where scientists tested crow blood samples for cholesterol levels. A total of 140 crow nestlings from environments ranging from rural to urban were selected for the study, which found that cholesterol levels increased the closer birds lived to urban landscapes.

In order to determine the cause of these increased levels, the researchers also fed crow nestlings from rural New York a diet of cheeseburgers from fast food restaurant McDonald's. These birds developed high cholesterol levels akin to the samples taken from city birds in California.

It's unclear at this time whether these increased cholesterol levels are harmful in crows, at least at the levels that were detected. Though too much cholesterol can have serious long-term consequences in humans, the substance isn't inherently unhealthy and, in the case of these birds, was associated with better body condition scores when compared to rural nestlings that weren't chowing down on burgers.