It's not foolproof. The existing implementation only detects the right food 85 percent of the time, and it can't tell whether you're eating a healthy or junky version of a given foodstuff (a common problem with cereal). However, the creators believe they could solve this by adding a biomonitor that looks for blood sugar levels and other telltale signs of specific meals. If the technology advances far enough, you could reliably use it to tackle diabetes, obesity and other conditions where each bite could be a big deal.