By today’s medical definition, Brad Pitt is overweight, and Russell Crowe is obese. The standards are even tougher for women. But are those extra pounds really that bad? Maybe it’s time we all lighten up about fat. In this hour of To the Best of Our Knowledge, why one expert says America’s...Read more






Scientists are launching one of the most audacious projects ever conceived: a detailed map of the human brain, neuron by neron, synapse by synapse. For some scientists...