Well, it seems there is a positive sign it may be associated with your intelligence.
According to Shared, spilling food or drink isn't clumsiness, but your brain prioritising important things in your mind, and whatever you're eating or drinking is secondary.
And typically, distracted or disorganised brains mean “the more unorganized your brain is, the more intelligent you are,” (according to the author of 'Where Good Ideas Come From: The Natural History of Innovation', Steve Johnson.)
Another study suggests that messy eating is a sign of "passion", rather than sloppiness.
“Keeping a little glimmer of that wide-eyed, high-chair desire to play with our food will ensure that dining continues to be the kind of lifelong exploration that’s both invigorating and satisfying."
So if you tend to make a mess while you're eating, take solace in the fact that your brain is too hard at work to focus on the smaller things. And maybe just avoid wearing anything that's white or easy to stain...