Andrew Huberman

Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science-based tools for mental health, physical health, and performance.

I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine.

Today, we are going to discuss sugar, in particular, how our nervous system regulates our sugar intake and our seeking of sugar.

We are going to place sugar into its proper context.

The way I want to start off by doing that is to tell you a little bit of what happens when we eat and a little bit of what the brain does to respond to those events.

So what happens when we eat?

let's just take a, what I call top contour view of the hormonal response to ingesting food.

Anytime we eat, that is the consequence of a number of things that happened before we ate.

There's a hormone in our brain and body called ghrelin, spelled G-H-R-E-L-I-N.

Ghrelin is a hormone that increases

depending on how long it's been since we ate last, okay?

So the longer it's been since we had a meal, ghrelin levels are going to be higher and higher and higher.

And it essentially makes us hungry by interacting with particular neurons in an area of the brain called the arcuate nucleus of the hypothalamus and some other areas as well, like the lateral hypothalamus.

And then when we eat, typically what happens is ghrelin levels go down.

So it's a very logical system.

Now, when we eat, assuming that we eat carbohydrates, but even if we just eat some protein and some fats, we will experience a slight, or in some cases, a large rise in blood glucose.

Blood glucose is simply blood sugar.

And the body and brain

We should say in particular, the nervous system doesn't function well if blood sugar is too high or too low.

So as a consequence, we have another hormone which is released from the pancreas, which is called insulin, which helps regulate the amount of glucose in the bloodstream.