I'm probably not alone when I say that cupcakes are perfect. The only thing better than a cupcake is a plate of cupcakes. Better still is an even bigger plate.

It's this all-too-human appetite for high-calorie food (and more food) that has led to 67 percent of this country's population to be overweight.

So why do our bodies—not to mention our tastebuds—so readily crave foods that are ultimately harmful? The question is asked by Time.com, which features an in-depth article, called The Science of Appetite.

It seems that we have our ancestors to thank (or blame) for our cravings for calorie-dense foods. They needed extra calories to survive drought, disease, famine, and boar hunts gone awry. The fittest survived by maximizing their calorie intake, and storing it in the most efficient ways.

Today, many of us face the opposite challenge. Heavily-processed, calorie-dense foods are everywhere, and these days the fittest survive by limiting their cupcake consumption.

Meanwhile, scientists are hard at work trying to understand what triggers appetite and cravings. The article contains a lot of information about current obesity research, especially the hormones that control our appetites. (Much of the science is too dry for me, though I did get a kick out of the fact that the hunger hormone is called ghrelin— which sounds an awful lot like gremlin.)

Anyway, it seems to me that while science parses out which chemicals are lighting up our brains, and which are giving our stomachs the green light, I'm still stuck with the challenge of turning down a cupcake.

When faced with a cupcake, the last thing I'm worried about is the survival of species.