How do we define healthy food? Choosing a carrot over a cookie seems like a good idea, but how do you know the carrot you're choosing is actually as nutritious as the next? Consumers have had few cues for determining the relative nutritional value of specific fruits and vegetables, because nutrient density has not previously been measurable at the point of purchase. Spectroscopy is a well-developed technology that can discern the makeup of materials using a noninvasive flash of light. That sparked an idea... Imagine going to the grocery or farmers market, flashing a light at several different carrots to compare their nutritional value in real-time. Readings might show that some carrots are nutrient-dense, while others are not. Which ones would you buy? Would you start to choose food based on how good it was for you and your family? The power of that collective choice might just transform the way we grow food and how we understand the value of soil. Dan Kittredge has been an organic farmer for more than 30 years. After working globally in the late 90s and early 2000s with farmers, NGOs, and researchers across India, Russia, and Central America, Dan returned to the U.S. and in 2010 launched the Bionutrient Food Association in order to ignite a movement around food quality. Dan has become one of the leading proponents of “nutrient density,” and works to demonstrate the connections between soil health, plant health, and human health.Dan launched the Bionutrient Institute with open-source science partners Our-Sci and FarmOS to lead the effort to identify and increase nutrition in the food supply. The Bionutrient Institute engineered and launched a hand-held consumer spectrometer, the Bionutrient Meter, designed to test nutrient density at the point of purchase and bring transparency to the marketplace. This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at https://www.ted.com/tedx