How Different Diets Impact Your Health | Dr. Christopher Gardner

**Andrew Huberman** (0:00)
Welcome to the Huberman Lab podcast, where we discuss science and science-based tools for everyday life. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. My guest today is Dr. Christopher Gardner. Dr. Christopher Gardner is a professor of medicine and director of nutrition studies at Stanford University. Dr. Gardner has conducted groundbreaking research on dietary interventions for over 25 years, focusing on what dietary interventions reduce weight and inflammation and for generally improving physical health. He is known for doing extremely well controlled studies of nutrition, where calories, macronutrients, so protein, fat and carbohydrates, and food quality are matched between the different groups and not simply comparing one intervention to the so-called standard American diet, as so many other nutrition studies do. As such, his work has been published in prestigious journals, such as the Journal of the American Medical Association and the New England Journal of Medicine. Today, we discuss several important nutritional controversies and we examine what the science actually tells us. First, we explore protein requirements, how much protein we actually need, and do those needs change based on activity levels, age and health status. And I should say that even though we started out with rather discrepant stance on this, we converge on an answer that I think will be satisfying, at least to most people. And then you can tailor that answer to your unique needs. We then examine the ongoing debate between vegetarian, vegan, and omnivore diets for optimal health. And we dive into whether plant proteins are truly inferior to animal proteins, as is often claimed. We also discuss the role of fiber in the diet and the emerging science on fermented foods and their powerful anti-inflammatory effects. Throughout today's conversation, we focus on food quality and not just macronutrient ratios or calories and how those can impact health outcomes. As you'll hear, Dr. Gardner and I don't agree on every nutritional recommendation, particularly how much protein people need and the discrepancy in views about animal-based proteins versus plant-based proteins. But by the end, I do believe that we converge on themes that everyone, regardless of their dietary preference, ought to be able to benefit from. As always, we provide you with science-based, actionable information that you can apply to your daily life. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero cost to consumer information about science and science-related tools to the general public. In keeping with that theme, this episode does include sponsors. And now for my conversation with Dr. Christopher Gardner. Professor Christopher Gardner, so nice to meet you and to have you here.

**Christopher Gardner** (2:36)
Happy to be here, off Stanford campus, talking to you.

**Andrew Huberman** (2:38)
That's right. Even though we've both been there a very long time, it is a big place, and so we haven't had the chance to interact directly. But of course, I know who you are, and I'm very familiar with much of your work, but you'll tell us about more of it today. To kick things off, I want to know, is it possible that even though all human beings are, I presume, the same species, that some of us might thrive perhaps on one form of diet, and others might thrive perhaps on a different form of diet? In other words, how do we justify talking about the quote unquote best diet for a given age demographic level of activity, et cetera? If one were to look at social media or even just the history of nutrition in this country, one can almost reflexively lean on the idea that maybe we all need something different and some experimentation and discovery is needed. So do we need different diets or is there a best diet?

**Christopher Gardner** (3:40)
So there isn't one best diet, and I don't think we need different diets. We're just incredibly resilient and we can do crazy wild things. So the way I start my human nutrition class at Berkeley with students is in the very first class, I point out the Tarahumara Indians who are like world class ultra marathon runners, mostly corn and beans, like total carb. And then you can look at the Alaskan Inuits who for centuries lived on whale and blubber and polar bear and things like that. So that was like total fat and total carb. And they thrive. There's really no diabetes, no heart disease, no cancer. But eating all their local indigenous diets. Michael Pollan has a great quote on this, the author of Omnivore's Dilemma. And he says, if you really look around the world, it is amazing how much variety there is in a diet that people can thrive on. Except the one that doesn't work is the American diet, the standard American diet because it's full of processed packaged food. And the sad thing is that the Tarahumara Indians now eat a lot of crap.