Even though the human tongue can detect four flavors--sour, bitter, salty, and sweet, humans are naturally drawn to the sweet flavor. Some people would claim that this is because we, as humans, are the evolved primates who are used to eating fruits. However, researches point that the inclination to sweet food are highly caused by genetics. In an experiment conducted by Danielle R. Reed, they found out that genetic factors account for approximately 30% of variation in sweetness from person to person. Hence, it is our DNA that determines how sensitive we are to a certain flavor be it sour, bitter, salty or sweet. On the other hand, neuroscientists explain that sugar leads to dopamine release -- an area associated with motivation, novelty, and reward. Thus, we tend to be addicted to the "good" feeling brought about by eating sweet foods.