(NBC News/Maggie Fox) — It might come as a surprise to people bombarded with pictures of their friends' dinners on Facebook and Instagram, but users of Twitter don't tweet much about their food and talk most about coffee and beer, a new study shows.

And when it comes to mentioning exercise, walking outscores everything else by a huge margin.

It's not the most rigorous scientific study, but the team at the University of Utah was using federal grant money to try to see if social media can tell us anything about the nation's health.

"We collected 80 million geotagged tweets from 603,363 unique Twitter users across the contiguous United States," the team wrote in the Journal of Medical Internet Research - Public Health.

Only about 5 percent of tweets even mentioned food, they found, and fewer than 2 percent mentioned physical activity.

The top 10 tweeted foods:

  • coffee
  • beer
  • pizza
  • Starbucks
  • IPA (beer)
  • wine
  • chicken
  • barbecue
  • ice cream
  • tacos

The team counted 250,000 tweets mentioning coffee and more than 200,000 mentioning beer.

Fewer than 50,000 mentioned bacon and only about 30,000 mentioned salad. Maybe 75,000 mentioned ice cream or tacos, they reported.

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