The Food That Makes You Feel Tired and Lazy

By Laura Kenney for YouBeauty.com
Could your eating habits be causing your exhaustion?

The Food That Makes You Feel Tired and Lazy

We've all felt like a sloth after eating an entire bag of chips. But in the world of nutrition research, an age-old chicken-and-egg debate still rages on: Does eating junk food make you lazy, or does laziness make you eat junk food?

New research from UCLA points to the former. Eating sugary, processed, and high-fat foods can actually cause tiredness, a lack of motivation and decreased performance, according to a study published in the April 10 issue of Physiology & Behavior.


Thirty-two female rats were placed on one of two diets for six months. The first was a standard (read: healthy) rat's diet of unprocessed foods like ground corn and fish meal. The second was made up of highly processed foods that included substantially more sugar, similiar to a human junk food diet. After three months, the 16 rats on the junk food diet became much fatter than the others – But they got lazier too.

As part of the study, the rats were given a task in which they were required to press a lever to receive a food or water reward. The rats on the junk food diet demonstrated impaired performance, taking longer breaks than the lean rats before returning to the task. In a 30-minute session, the overweight rats took breaks that were nearly twice as long as the lean ones.

After six months, the rats' diets were switched, and the overweight rats were given the more nutritious diet for nine days. This change, however, didn't help reduce their weight or improve their responses. The reverse was also true: Placing the lean rats on the junk food diet for nine days didn't increase their weight noticeably or result in any reduction in their motivation on the lever task. These findings suggest that a pattern of consuming junk food, not just the occasional binge, is responsible for obesity and cognitive impairments, lead researcher Aaron Blaisdell said.

So, do people who are overweight become less healthy or do less healthy people become overweight?

"Overweight people often get stigmatized as lazy and lacking discipline," says Blaisdell. "We interpret our results as suggesting that the idea commonly portrayed in the media that people become fat because they are lazy is wrong. Our data suggest that diet-induced obesity is a cause, rather than an effect, of laziness. Either the highly processed diet causes fatigue or the diet causes obesity, which causes fatigue."

Blaisdell, 45, is practicing what he's preaching. He changed his diet more than five years ago to avoid processed food, bread, pasta, grains and food with added sugar. He eats meats, seafood, eggs, vegetables and fruits, and he has seen dramatic improvements in his health, both physically and mentally.

"I've noticed a big improvement in my cognition," he said. "I'm full of energy throughout the day, and my thoughts are clear and focused."

The opposite of a sloth.

More from YouBeauty.com

MORE: Science Determines Your Healthiest Diet 

66 Clever Ways to Keep Your Road Trip Healthy

From road trip food to on-the-go health hacks, here's all you need to have a safe vacation from city to city.

Summer is the perfect time for a road trip! But do you wonder how you can stay healthy with all the fast food and potential health issues along the way? Things can go downhill for everyone pretty quickly. Here are 66 clever and easy tips for keeping the trip on track for health and fun.

1. Pack Compact Snacks to Avoid Overeating

Reuse a cleaned creamer bottle or fill up a new tackle box with healthy bites like nuts, seeds, berries, dried fruit, and granola. This way, you'll cut down on multiple snack bags and boxes and won't over-indulge because you can only have a small handful at a time.

Keep Reading Show less