Robert Lustig is a person who talks about healthy eating and why it's important to eat food that's good for your body. He thinks that some foods have too much sugar in them which can be bad for your body if you eat too much of it. He also believes that some people eat too much food and don't get enough exercise, which can also be bad for their bodies. So, he wants to help people learn more about how to make better choices when it comes to what they eat and how to keep their body healthy.