I read this at the gym earlier today.  When I think about my cravings and when I have them, this has some merit. 

You crave: Salty or greasy food

It could mean: You’re slightly dehydrated. “Salt holds water in,” says Glassman. “Your body may be trying to hang onto the fluids it’s got. Aim for eight glasses of water a day.

You crave: Candy or chocolate

It could mean: You need protein. Without its slow-releasing energy, your body will try to get a quick fix to boost blood sugar. Try a cup of yogurt—it has 24 percent of your daily total.

You crave: Bread or pasta

It could mean: You don’t eat enough! Starches are already partially broken down, so your body knows carbs will give it energy fast. Be sure to eat at least 1,200 calories a day.