The Surprising Reason People Are Overweight, with Dr. Robert Lustig

Dr Daniel Amen and Tana Amen BSN RN On The Brain Warrior's Way Podcast

In Robert Lustig’s early work as a pediatric endocrinologist, he began studying the effect certain molecules had on the body’s organs. What he found was a stunning connection between fructose and liver function, which helps explain the reason for today’s obesity epidemic. In the first episode of a series with the author of “Fat Chance,” Dr. Daniel Amen and Lustig discuss how and why fructose is making people fat.

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Dr. Daniel Amen: Welcome to the Brain Warrior's Way Podcast. I'm Dr. Daniel Amen.
Tana Amen: And I'm Tana Amen. In our podcast, we provide you with the tools you need to become a warrior for the health of your brain and body.
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Dr. Daniel Amen: Welcome everybody, I am so excited for this week and maybe we'll call it the bitter truth week. I am here with my new friend Rob Lustig, who is a professor of pediatrics in the division of endocrinology at UC San Francisco. He is also the chief science officer at Eat Real, a non-profit dedicated to reversing childhood obesity and type two diabetes. Dr. Lustig consults several childhood obesity advocacy groups and government agencies. His books, which are just amazing and include the New York Times bestseller Fat Chance, the Fat Chance cookbook, and Sugar Has 56 Names: A Shopper's Guide. And his new book is called The Hacking of the American Mind, which is really interesting because I actually submitted a proposal for a book called Flying Blind and The Raping of the American Mind. But then I thought, "Okay, that's a little over the top."
Dr. Robert Lustig: Raping, hacking. It's all the same.
Dr. Daniel Amen: We actually just met a few weeks ago.
Dr. Robert Lustig: Yeah, yeah.
Dr. Daniel Amen: At the [crosstalk 00:02:06].
Dr. Robert Lustig: I've known about you for a while and I take it you have known about me for a while so it was good that we finally actually laid eyes on each other.
Dr. Daniel Amen: Yeah. Well, it's so funny because you're in line for talking to me and I see you and I immediately recognize you from the YouTube talk Sugar, The Bitter Truth. If you haven't watched that, and it's more than an hour, but it's fascinating. Literally, it'll change your life. I watched that 10 years ago when it first came out. It now has 8,000,000 views or more and it just changed how I thought about sugar, and about fruit juice in particular. So in this podcast, so this week we're going to talk a lot about sugar and society and what Rob has learned, but I want you to tell our listeners and our viewers who you are and why you do what you do.
Dr. Robert Lustig: I'm a pediatric endocrinologist. So I study hormone problems in children. I started out being interested in why boys were boys and girls were girls from the neck up. I am a neuroendocrinologist. So I was studying how the brain controls hormones, how hormones control the brain, how testosterone causes differences in brain formation and development, and what that meant for individuals and for various disease States. That's what I started doing and couldn't get funded for it. Well, I was also interested in obesity and I had this one idea back in the early to mid-'90's about whether or not insulin played a role in weight gain. Now up to that point, people had thought, "Well, yes, insulin levels are high in the obese, but it's a result of the weight rather than a cause."
Well, there is a disorder in neuroendocrinology, which you may or may not have heard of called hypothalamic obesity. So these are kids who had brain tumors, and because of the tumor their hypothalamus is shot. Their hypothalamus is either dead from the surgery, or from the tumor itself, or from the radiation and they become massively obese. Now, it was around the mid-'90s when we had discovered this hormone called leptin. It was about 1994 and I postulated back then that these kids, because of the brain damage couldn't see their leptin, and because they couldn't see it their brain thought they were starving. So you can't fix a brain or, actually, I take it back. You can.
Dr. Daniel Amen: That's what we do here.
Dr. Robert Lustig: Okay? But back then we couldn't do such a good job.
Dr. Daniel Amen: And we didn't think about, right?
Dr. Robert Lustig: Right. We didn't think about it. Basically, these kids had anatomic damage to their brain. In particular the limbic system. So what could we do for them? So based on some old work in animals it would've appeared that getting the insulin down by cutting the vagus nerve, and there's a connection between the hypothalamus and the pancreas via the vagus nerve, cutting the vagus nerve reduces the amount of insulin that the pancreas releases and reduces the amount of weight gain in lesioned animals. So, well, I can't cut a vagus nerve. I'm not a surgeon. So I said, "Well, can we do the next best thing? Can we give a drug that would stop the pancreas from making so much insulin?" So we did that. We did a pilot study where we gave a drug called octreotide, which was usually used to suppress growth hormone secretion from growth hormone-secreting tumors of the brain of the pituitary, acromeglus gigantism, but we instead used it to suppress insulin release at the level of the pancreas. And low and behold, these patients started losing weight.
Dr. Daniel Amen: Wow.
Dr. Robert Lustig: And no one had ever described weight loss in any of these patients before, but they lost significant amounts of weight. And something even more remarkable occurred that basically spurred the rest of my career. Not only did they lose weight, but they started exercising spontaneously.
Dr. Daniel Amen: Wow.
Dr. Robert Lustig: These were kids who sat on the couch, ate Doritos and slept. And the reason was because their brains thought they were starving. So they didn't want to expend any energy, but when we got their insulin down with the medicine, now they had energy to burn and so they actually changed their lifestyle. So what this proved, and we did it again in a double-blind placebo-controlled trial. We also did it in adults who didn't have brain tumors and found the same phenomenon in a proportion of them.
What this proved was that the biochemistry drives the behavior and this shouldn't be too much of a shock, especially to you. Every thought is a protein phosphorylation. Everything that goes on in our brain is driven by biochemistry, by molecules. Your whole clinic is set up to fix those molecules, fix the hardware before you fix the software.
Dr. Daniel Amen: Right. I agree with you.
Dr. Robert Lustig: It's really hard to program a brain that doesn't work right.
Dr. Daniel Amen: Exactly.
Dr. Robert Lustig: So that's what we did. We fixed the problem where the problem was. We fixed the cause rather than the result. And I have basically taken that on going forward in all of my work knowing that ultimately sometimes we're smart enough to be able to figure out the cause. Sometimes we're not, but it's always upstream of where you think it is. What we're looking at is the result of the problem rather than the cause of the problem and you have to treat the cause if you're going to be successful.
Dr. Daniel Amen: So besides a tumor, why do people have high insulin levels?
Dr. Robert Lustig: Right. So that's the big question, okay? So tumors, that's like one in a million. Everyone's hyperinsulinemic today. Everyone's insulin level's two to four times higher than it used to be. Now, our glucoses are the same, but the amount of insulin that our bodies need to release to keep that glucose the same is two to four-fold higher than it was in 1970, and that's where the work that I delineate in Fat Chance really came from and basically I think is sugar. The dietary sugar, the sweet stuff. There's a reason for why I think that. Number one, it's gone up like crazy. Number two, the molecule in sugar that makes it sweet, called fructose. So sugar is two molecules, glucose and fructose. Glucose is the energy of life. That's what's in starch. That's not what we're talking about. We're talking about fructose.
It turns out fructose has a very specific biochemical profile. When you consume fructose, say a 20 ounce Coca-Cola, that fructose is all ending up in the liver. The liver cannot handle the load and the liver has no choice but to take that excess fructose and turn it into liver fat. And it is that liver fat that is mucking up the workings of the liver and is causing that insulin resistance, causing the pancreas to have to make more insulin to make delivered to its job, driving the weight gain and we have now done several studies to prove that.
So when you get the fructose out of the diet, in other words, you cut the sugar from the diet, the liver fat goes away, the pancreas makes it less insulin and the patient loses weight naturally, and the leptin starts working because the insulin was blocking the leptin. So basically we can reverse metabolic syndrome just by getting sugar out of the diet. So we think sugar is a primary, not the only, but a primary driver of the chronic disease epidemic that we see around the world today, and we are doing our best to try to stem the tide.
Dr. Daniel Amen: How can people learn more about your work? So they can get The Hacking of the American Mind, but I want you because it's just life-changing to go to YouTube and just search for the bitter truth. Sugar, The Bitter Truth with Robert Lustig and I want you to get your kids to watch it, and it's actually fairly detailed science but you make it easy to understand.
Dr. Robert Lustig: I appreciate that.
Dr. Daniel Amen: Because you're really masterful teacher.
Dr. Robert Lustig: Thank you.
Dr. Daniel Amen: How else can they learn about your work?
Dr. Robert Lustig: So what I would argue is number one, that video is now 10 years old. We have more out that's more recent that I think is actually more up to date and better. If you do just a YouTube look on my name you'll find a whole bunch of them. One's called Fat Chance Fructose 2.0 which I actually think is better, although not as many hits. There's a Ted Talk I did called Sugar: The Elephant in the Kitchen. Actually, what I would propose that people do is they take three hours of their time and they watch two movies, and they're both on Netflix. One is called Fed Up, which was produced in 2014 and it's a documentary that tells the story of how we got to where we are today. And the other is called Sugarcoated, which is a documentary also on Netflix which tells the story of why we got to where we are today. That is the corporate subterfuge, the fraud, the public relations campaign to exonerate sugar and make us all sick.
Dr. Daniel Amen: So when we come back, we're going to talk about sugar and the bitter truth. Stay with us.
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