This photographer captures images of the real food people eat around the world - and it's a lot less glamorous than what you might see on Instagram

But if your Instagram feed is filled with food photography, you might unknowingly be experiencing "visual hunger", a sensation that can have some of the same effects on the body as actual hunger: increased heart rate in anticipation of eating, salivating, and other neural activity across a network of brain areas.

A recent study published in the scientific journal "Brain and Cognition" argued that this form of "digital grazing" could have an indirect link to obesity, saying that "humankind is not doing such a great job in terms of optimizing the contemporary food landscape."

Photographer Martin Parr has been observing that landscape for over 25 years, taking photos of the food he's found aesthetically amusing from around the world. His new book, "Real Food", features photos of more than 200 dishes from 36 different countries.

Instead of feeding what he calls the food "propaganda" machine, Parr's images of popular foods are a bit less flattering, but all the more revealing.