Just Looking at Food on Instagram Could Make You Gain Weight

If you're doing Instagram right, it's impossible to open the app without finding something you desperately want to eat: 

[instagram ]https://instagram.com/p/8xLjNaCBQQ/?taken-by=cosmopolitan" data-instgrm-version="14" style="background:#FFF; border:0; border-radius:3px; box-shadow:0 0 1px 0 rgba(0,0,0,0.5),0 1px 10px 0 rgba(0,0,0,0.15); margin: 1px; max-width:540px; min-width:326px; padding:0; width:99.375%; width:-webkit-calc(100% - 2px); width:calc(100% - 2px);" >

[instagram ]https://instagram.com/p/8GhKQOCBRP/?taken-by=cosmopolitan" data-instgrm-version="14" style="background:#FFF; border:0; border-radius:3px; box-shadow:0 0 1px 0 rgba(0,0,0,0.5),0 1px 10px 0 rgba(0,0,0,0.15); margin: 1px; max-width:540px; min-width:326px; padding:0; width:99.375%; width:-webkit-calc(100% - 2px); width:calc(100% - 2px);" >

[instagram ]https://instagram.com/p/7_P4oACBT4/?taken-by=cosmopolitan" data-instgrm-version="14" style="background:#FFF; border:0; border-radius:3px; box-shadow:0 0 1px 0 rgba(0,0,0,0.5),0 1px 10px 0 rgba(0,0,0,0.15); margin: 1px; max-width:540px; min-width:326px; padding:0; width:99.375%; width:-webkit-calc(100% - 2px); width:calc(100% - 2px);" >

While you might think delicious-looking food is pretty harmless, a new review of studies in the journal Brain and Cognition suggests you've got it all wrong: "Regular exposure to virtual foods nowadays, and the array of neural, physiological, and behavioral responses linked to it, might be exacerbating our physiological hunger way too often," the authors write. In other words, seeing everybody and their mom post pictures of their every meal encourages you to feast every time they post regardless of your actual hunger level. Spend too much time scrolling through a food-heavy Instagram feed, and you could end up eating excess calories that contribute to weight gain.

It doesn't help that seeing images of food can physically affect you, making you salivate, messing with insulin levels, and even shaking up your heart rate — all in anticipation of eating the food you see.

And if you're already overweight, you may be even more likely to respond to images of high-calorie foods — particularly in parts of the brain responsible for registering rewards (cake!) and coordinating motor skills like hand-to-mouth movements and swallowing.  The worst part?  Seeing tons of photos associated with a particular taste decreases your enjoyment when you actually experience that taste, according to a study cited in the review. 

That said, you don't need to unfollow every friend who posts a pizza selfie to fend off unwanted weight gain: Because appetite and eating habits are pretty nuanced, experts can't say for sure whether digital grazing is directly causing an obesity crisis. But if you've put on a few pounds and your feed is full of food? Well, case solved. 

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