Hippocampal-dependent appetitive control is impaired by experimental exposure to a Western-style dietRoyal Society Open Science

What does the term ‘junk food’ mean to you? Synonyms include ‘unhealthy food’ or, as Michael Pollan calls it, ‘food-like substances’ and today we will see why it could also be called “addictive food that hijacks your brain leading to weight gain and poor memory.”

Researchers enlisted 110, healthy-eating college kids, and had them eat junk food for a week. They even paid them, challenging the saying you couldn’t pay me to eat that.

Fortunately for the participants, the junk food provided is the stuff we humans seem to crave: meals high in saturated fat, carbs, and sugar. Australian researchers referred to this as a “Western-style diet” which you might think is a jab at American’s food choices, and it is.

In the study, one group was fed junk food for breakfast, including a sugary milk shake, waffles, or fast food. Meanwhile, the control group was encouraged to continue business as usual. This study was designed to only change one meal per day to see how a Western diet affects cravings, memory, and appetite control.

“After a week on a western-style diet, palatable food such as snacks and chocolate becomes more desirable when you are full,” said Richard Stevenson, a professor of psychology at Macquarie. “This will make it harder to resist, leading you to eat more, which in turn generates more damage to the hippocampus and a vicious cycle of overeating.”

TAKEAWAY
Just one week of eating food high in saturated fat, carbs, and sugar lead to a weakening of appetite control. Researchers also noted a decrease in learning and memory, two functions of your brain’s hippocampus. This hijacking might explain why overeating junk food often seems uncontrollable, and why it’s rare to binge on carrots.