Sweet vs. Salty
The brain and taste preference
There's no taste map on your tongue. But there is a vast taste network in your brain. Genetics may influence how your brain judges and responds to tastes.
How the brain judges tastes
Many areas of your nervous system work together to influence your taste preferences. The tongue detects the molecules present in foods you eat and sends signals to a brain area, the "primary gustatory cortex", that helps identify their tastes. Another area, the "orbitofrontal cortex", then helps judge whether you like these tastes. And several other brain areas help determine your responses to pleasant flavors — like deciding to eat more.
Like almost all traits, taste preference is partly shaped by genetics, and partly by environment. Research identified 43 genetic markers where people can have variants that make them more likely to prefer sweet snacks or salty/savory snacks. A few of these 43 genetic markers are in or near genes involved in brain development or function (like CDH8, ELAVL2, AUTS2, and KCNA3). But most are near genes with a broad range of functions, perhaps reflecting the complexity of this trait.