The Bitter Truth About Sugar by Robert Lustig (Full Transcript)

Robert H. Lustig, a Professor of Clinical Pediatrics at University of California, San Francisco (UCSF), here details and explores the real truths about sugar that you perhaps never heard about much before. We thought it might be useful for our readers. So we decided to do a full transcript on his about 90-minute YouTube video called “Sugar: The Bitter Truth”. Hope you find it useful and informative. Please use the “The Bitter Truth About Sugar” slides below while reading this transcript…

The Bitter Truth About Sugar by Robert Lustig Slides [PDF file]



I’m going to tell you tonight a story and this story dates that about 30 years. This story has a little bit of something for everybody. It has a little bit of biochemistry, a little bit of clinical research, a little bit of public health, a little bit of politics, a little bit of racial innuendo. The only thing it’s missing is sex. But well, we can see what we can do about that too.

By the end of the story, I hope I will have debunked the last 30 years of nutrition information in America. And I would very much appreciate if at the end of the talk you would tell me whether or not I was successful or not.

Atkins versus Japanese diet

Okay. So in order to get you in the mood as it were, let’s start with a little quiz. What do the Atkins diet and the Japanese diet have in common? Anybody? Well you have the answers right – yes, never mind, that’s right. You have the answer right there.

So the Atkins diet of course is all fat, no carb. The Japanese diet is all carb, no fat. They both work. So what do they share in common? They both eliminate the sugar fructose. With that, think about what it means to be on a diet and what macro-nutrients you are eating and which ones you’re not. And then we’ll go from there and I’ll try to explain how this all works.

So you’ve all heard about the obesity epidemic. Here are the numbers. These are the Anne Haines database body mass index (BMI). Everybody knows what that is now. Histograms marching ever rightward as time has gone on… this was what was projected for 2008 in blue. We had so far exceeded and surpassed this – it’s not even funny – from 2003. The reason I show this is not just to show that the obese or getting obese, or of course that’s true, but in fact, the entire curve has shifted. We all weigh 25 pounds more today than we did 25 years ago, all of us.

Now it is often said that obesity is the ultimate interaction between genetics and environment. But having said that our genetic pool did not change in the last 30 years. So tonight we’re going to talk about the environment rather than genes.

Obesity epidemic

Now in order to talk about the environment we need to talk about what is obesity, and of course, you’re all familiar with the basic concept of the first law of thermodynamics, which states that the total energy inside a closed system remains constant. Now in human terms, the standard interpretation of this law is the following: If you eat it, you better burn it or you can store it. Now who here believes that? Oh come on, you all do.

I used to believe that. I don’t anymore. I think that’s a mistake. I think that is the biggest mistake and that is the phenomenon I’m going to try to debunk over the course of the next hour, because I think there’s another way to state the law, which is much more relevant and much more to the point. Before I get there, of course, if you believe that these are the two problems: calories in, calories out, two behaviors – gluttony and slough. After all you see anybody on the street, he’s a glutton and slough. You know Tommy Thompson said it on the TV show, “we just eat too damn much”.

Well, you know if that were the case, how do the Japanese do this? Why are they doing bariatric surgery on children at Tokyo Children’s Hospital today? Why are the Chinese? Why are the Koreans? Why are the Australians? I mean, all these countries who have adopted our diet all suffer now from the same problem, and we’re going to get even further in a minute.

There is another way to state this first law. And that is, if you’re going to store it, that is biochemical forces that drive energy storage – we will talk about what they are in a few minutes – and you expect to burn it, that is normal energy expenditure for normal quality of life, because energy expenditure and quality of life are the same thing. Things that make your energy expenditure go up, make you feel good — things that make your energy expenditure go down, like starvation, hypothyroidism, make you feel lousy. And how many calories you burn and how good you feel are synonymous.

So if you’re going to store it, that is an obligate weight gain set up by a biochemical process and you expect to burn it, that is normal energy expenditure for normal quality of life, then you’re going to have to eat it. And now all of a sudden these two behaviors, gluttony and slough are actually secondary to a biochemical process, which is primary. That’s a different way to think about the process and it also alleviates the obese person from being the perpetrator but rather the victim, which is how obese people really feel, because no one chooses to be obese. Certainly no child chooses to be obese.

Oh, you say, oh yes, sure I know some adults who don’t care. You know Rossini, the famous composer, he retired at age 37 to a lifetime of gastronomic debauchery. Okay, maybe he chose to be obese. But the kids I take care of an obesity clinic do not choose to be obese. In fact, this is the exception that proves the rule. We have an epidemic of obese six-month olds.

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Now if you want to say that it’s all about diet and exercise, then you have to explain this to me. So any hypothesis that you want to proffer that explains the obesity epidemic, you’ve got to explain this one too. And this is not just in America, the six-month old obese kids but these are around the world now. So you’re your minds and let’s go and figure out what the real story is.

Calorie intake & leptin

Now let’s talk about calorie intake, because that’s what today is about. We’re going to talk about the energy intake side of the equation. Sure enough we are all eating more now than we did 20 years ago. Teen boys are eating 275 calories more. American adult males are eating 187 calories more per day. American adult females are eating 335 calories more per day. No question. We’re all eating more. Question is why? How come? Because it’s all there, you know what it was there before. We’re all eating more.

There is a system in our body which you’ve heard about over the last couple of weeks called leptin. It’s a hormone that comes from your fat cell, tells your brain “You know what, I’ve had enough. I don’t need to eat anymore. I am done and I can burn energy properly”. Well, you know what, if you’re eating 187 or 335 calories more today than you were 20 years ago, your leptin ain’t working, because if it were, you wouldn’t be doing it whether the food was there or not.

So there’s something wrong with our biochemical negative feedback system that normally controls energy balance. And we have to figure out what caused it and how to reverse it, and that’s what tonight is about. But nonetheless there are 275 calories we have to account for. So where are they? Are they in the fat? No, they are not in the fat. 5 grams 45 calories out of the 275, nothing. In fact, it’s all in the carbohydrate. 57 grams, 228 calories, we’re all eating more carbohydrate. Now you all know back in 1982, the American Heart Association, the American Medical Association and the US Department of Agriculture admonished us to reduce our total fat consumption from 40% to 30%. Everybody remember that? That’s how Entenmann’s fat-free cakes came into being.

So what happened? We did it. We’ve done it. 40% down to 30% and look what’s happened to the obesity metabolic syndrome, non-alcoholic fatty liver disease, cardiovascular disease, stroke prevalence, all jacked way up as our total fat consumption as a percent has gone down. It ain’t the fat people. It ain’t the fat. So what is it? Well, it’s the carbohydrate. Specifically, which carbohydrate? Well, beverage intake – 41% increase in soft drinks, 35% increase in fruit drinks, fruit aids, whatever you want to call them. Just remember down here, one can of soda a day is 150 calories, multiply that by 365 days a year and then divide that by the magic number of 3500 calories per pound, if you eat or drink 3500 calories more than you burn, you will gain 1 pound of fat. And that’s the first law of thermodynamics. No argument there. That’s worth 15.5 pounds of fat per year. One soda a day is 15.5 pounds per year. Now you’ve all heard that before. That’s not news to you.

The question is, how come we don’t respond? How come leptin doesn’t work? How come we can’t stay energy stable? That’s what we’re going to get to.

Coca-Cola conspiracy

So I call this slide very specifically the Coca-Cola conspiracy. Anybody here work for Coke? Pepsi? Okay, good. All right. So this over here – 1915 the first standardized bottle of Coca-Cola out of Atlanta. Anybody remember this bottle? I remember this bottle because my grandfather in Brooklyn took me on Saturday afternoon down to the local soda shop on Avenue M and Ocean Avenue and every Saturday afternoon I have one of these. I remember very well.

Now if you drank one of those everyday assuming of course that the recipe hasn’t changed, because after all only two people in the world know the recipe and they’re not allowed to fly in the plane at the same time, right, you know that? Assuming the recipe hasn’t changed, if you drank one of those everyday for a year, 6.5 pounds, that will be worth 8 pounds of fat per year.

Now in 1955 after World War II and sugar became plentiful, again it wasn’t being rationed, we have the appearance of the 10-ounce bottle – the first one that was found in vending machines. You probably remember that one as well. Then in 1960 the ever ubiquitous 12-ounce can worth 16 pounds of fat per year, and of course today this over here is a single unit of measure, 20 ounces, anybody know how many servings are in that bottle? 2.58 ounce servings, that’s right. Anybody know anybody who gets 2.58 servings out of that bottle? That’s a single serving. So that will be worth 26 pounds of fat per year if you did that everyday and then of course over here we have the 7-Eleven Big K, Thirst Buster, Big Gulp whatever you want to call it, 44 ounces worth 57 pounds of fat per year and if that wasn’t bad enough, my colleague Dr. Dan Hale at the University of Texas, San Antonio tells me that down there they got a Texas sized Big Gulp. 60 ounces of Coca-Cola, a Snickers bar and a bag of Doritos all for $0.99. If you did that everyday for a year, that would be worth 112 pounds of fat per year.

So why do I call it the Coca-Cola conspiracy? Well what’s in Coke? Caffeine. So what’s caffeine? It’s a mild stimulant, it’s also a diuretic, makes you pee free water. What else is in Coke? We’ll get to the sugar in a minute. What else? Salt – 55 mg of sodium per can, it’s like drinking a pizza. So what happens if you take on sodium and lose free water, you get thirstier. So why is there so much sugar in Coke? To hide the salt. When was the last time you went to a Chinese restaurant and had a sweet and sour pork? Everybody remember new Coke, 1985, more salt more caffeine. They knew what they were doing. That’s the smoking gun. That’s why it’s the Coca-Cola conspiracy.

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Soft drinks – the cause of obesity?

Well it depends on who you ask. If you ask the scientist for the National Soft Drink Association, he will tell you there is absolutely no association between sugar consumption and obesity. If you ask my colleague Dr. David Ludwig, remember I’m Lustig, he is Ludwig. He does what I do at Boston Children’s Hospital. Someday we’re going to open a law firm. Each additional sugar sweetened drink increase over a 19-month follow-up period in kids increased their BMI by this much and their odds risk ratio for obesity by 60%. That’s a prospective study on soft drinks and obesity.

If you look at meta-analyses – a conglomeration of numerous studies subjected to rigorous statistical analysis – 88 cross-sectional longitudinal studies regressing soft drink consumption against energy intake, bodyweight, milk and calcium intake, adequate nutrition all showing significant associations and some of this being longitudinal, this came from Kelly Brownell’s group at Yale. I should comment a disclaimer – those studies that were funded by the beverage industry showed consistently smaller effects than those that were independent. Wonder why?

Now how about the converse – what if you take the soft drinks away? So this was the fizzy drink study from Christchurch England James [Adolph] British Medical Journal where they went into schools and they took the soda machines out – just like we did here in California. We haven’t seen the data yet but they went and did it for a year. So the prevalence of obesity in the intervention schools stayed absolutely constant, no change whereas the prevalence of obesity in the controlled schools where nothing changed continued to rise over the year.

Soft drinks and Type 2 diabetes?


So how about type 2 diabetes? Are soft drinks the cause of type 2 diabetes? Well this study from JAMA in 2004 looked at the relative risk ratio of all soft drinks, cola, fruit punch and found a very statistically significant trends of sugared soft drinks, fruit aids etcetera causing type 2 diabetes and you know we’ve got just as big a problem with type 2 diabetes as we do with obesity for the same reasons. This was a sugar sweetened beverage (SSBs) against risk for type 2 diabetes in African American women, looking here at sugar sweetened soft drinks, just the downward arrow shows that there was a significant rise as the number of drinks went up. You can see that here whereas orange and grapefruit juice interestingly did not. So, two different studies, two different increases in type-2 diabetes relative to soft drink consumption.

So what’s in soft drinks?

Well, in America it’s this stuff, right? High fructose corn syrup. Everybody’s heard of it, right? It’s been demonized, something awful so much so that the corn refiners industry has launched a mega-campaign to try to absolve high fructose corn syrup of any problems which we’ll talk about in a moment. But the bottom line is this is something we were never exposed to before 1975. And currently we are consuming 63 pounds per person per year – everyone of us. 63 pounds of high fructose corn syrup. That’s America.

What is high fructose corn syrup?

Well, you’ll see in a minute. It’s one glucose, one fructose. We’ll talk about those at great length. One of the reasons we use high fructose corn syrup is because it’s sweeter. Here is sucrose. This is cane or beet sugar, standard-table sugar, you know, the white stuff. And we give that an index in sweetness of 100. So here is high fructose corn syrup. It’s actually sweeter. It’s about 120. So you should be able to use less, right? Wrong. We use just as much. In fact, we use more.

So here is lab fructose over here, crystalline fructose, and they are starting to put crystalline fructose into some of the soft drinks. They are actually advertising it as a good thing. And that’s got a sweetness of 173. So you should be able to cut that way back, right? They are not.

Lactose down here, milk sugar, that’s not sweet at all. And glucose I should point out over here 74, it’s not particularly sweet and we’re going to get to that at the end and what goes on with glucose. But anyway there’s why we use it: it’s sweeter. It’s also cheaper as I’ll show you.

Here’s high fructose corn syrup. One glucose, one fructose. Notice the glucose is a 6-membered ring. The fructose is a 5-membered ring. They are not the same. Believe me, they are not the same. That’s what this whole talk is about. It’s how they are not the same.

And here is sucrose. And they are just bound together by this ether linkage. We have this enzyme in our gut called sucrose. It kills that bond in 2 seconds-flat and you absorb it. And basically high fructose corn syrup sucrose, it’s a non-issue. It’s a wash. They are the same. And they know that they are the same – the soft drinks companies and the corn refiners. Because here are their missives. This comes from the corn refiner association: “Obesity research shows high fructose corn syrup metabolizes and impacts satiety similar to sugar.” Indeed it does.

Hunger and satiety profiles, energy intake, following ingestion of soft drinks. Bottom line: research supported by the American Beverages Institute and the Corn Refiners Association. They are correct. There is absolutely no difference between high fructose corn syrup and sucrose. So much so that the Corn Refiners Association in attempt to capture market share came out with this entire ad campaign. You probably saw it on the back page of the New York Times. It was on TV. It’s everywhere.



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