Calories are at the heart of the two most important food issues facing the world today: food security and obesity. Yet, "calories can't be seen, they can't be smelled and they can't be tasted," leading to confusion about what exactly a calorie is and why it matters, said Marion Nestle in a lecture on February 20, 2012.

Nestle, professor of nutrition, food studies and public health at New York University, was the inaugural speaker of the Joyce Lindower Wolitzer '76 and Steven Wolitzer Nutrition Seminar, hosted by the Division of Nutritional Sciences' undergraduate nutrition group HealthNuts.