Robert Lustig: How Worried Should We Be About Sugar? Sugar is a major culprit in diseases such as obesity, diabetes and dementia—and because it's in almost everything we consume, Dr. Robert Lustig says it's time to get more proactive.

Robert Lustig: How Worried Should We Be About Sugar?

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OK. So Mark Bittman is saying that, like, 40 percent of the stuff in grocery stores isn't real food. But if you had to estimate what percentage of the stuff in grocery stores has added sugar?

ROBERT LUSTIG: I don't have to estimate, it's 74 percent.

RAZ: What?

LUSTIG: Seventy-four percent of all of the food in the store has been spiked with added sugar in some fashion.

RAZ: Is it hidden in plain sight?

LUSTIG: Oh, absolutely.

RAZ: This is Dr. Robert Lustig. He's a pediatrician and a researcher at the University of California in San Francisco.

LUSTIG: So there are 56 names for sugar. I mean, did you know panocha was sugar?

RAZ: No (laughter).

LUSTIG: You know, did you know - I mean, demerara, that's even - that's almost famous now.

RAZ: Yeah.

LUSTIG: Apple puree or evaporated cane juice...

RAZ: Yeah.

LUSTIG: ...That's my favorite because cane juice, oh, you know, it's juice. It's healthy, right.

RAZ: Yeah.

LUSTIG: What happens when you evaporate cane juice? So you get sugar.

RAZ: Robert Lustig studies sugar, how it's managed to sneak its way into our diet and what it does to our bodies.

LUSTIG: We've replaced a real food diet with a processed food diet because it's cheaper. It's portable. It's convenient. Kids like it and it's addictive.

RAZ: And like any addictive substance, Robert says, sugar can be toxic, especially because so many of us eat too much of it. Here's Robert Lustig on the TED stage.


LUSTIG: Does sugar cause diabetes? Well, everyone says, well, yeah, but it's because of the calories. Sugar are empty calories. That's the mantra. It is not. This is absolutely not true. Sugar are toxic calories. So here's the way to look at this. The prevalence of diabetes worldwide as we speak right now - who's worst - Saudi Arabia, Kuwait, UAE, Qatar and Malaysia. Why them? No alcohol, but they got soft drinks like they're going out of style. 'Cause it's hot and the water supplies are a question mark and no alcohol. This is their reward.

Studies from Europe show that if you consume one soda per day, your risk for diabetes goes up 29 percent irrespective of the calories, irrespective of your weight, irrespective of anything else you eat. We've shown that for every hundred-fifty calories the world consumes, diabetes prevalence goes up a total of 0.1 percent, which is nothing. But if those 150 calories happen to be a can of soda, diabetes goes up 11-fold. And we're not consuming one can of soda. We're consuming two-and-a-half. So 29 percent of all the diabetes in the world is due to sugar and sugar alone. This study actually satisfies both the scientific and legal criteria for proximate cause. You have to be able to show that something causes something else before you can do something about it. Well, we've proven it. We've shown it.

RAZ: So how toxic is it?

LUSTIG: Well, it causes disease. Number one, type-two diabetes.


LUSTIG: Number two, heart disease.


LUSTIG: Number three, fatty liver disease, which is actually the biggest epidemic on the planet. And finally tooth decay. So there are the four diseases where we have causation. There are two diseases where we have correlation, and so I don't talk about those much. But we have correlation for sugar in cancer and sugar and dementia.

RAZ: Wow.

LUSTIG: But we don't have causation yet, but people are working on it.

RAZ: So fruit is fine, right? I mean, I eat lots of fruit every morning.

LUSTIG: So when you consume fruit, you're getting the fiber with it. And that's what's important is that that fiber not be pulverized, not be removed. And, of course, that's what processed food is - you remove the fiber.

RAZ: So basically you got to eat whole fruit?

LUSTIG: Yeah. Oh, yeah, absolutely. Let's say you didn't consume it as fruit. Let's say you consume that as a soda. You can't metabolize it fast enough as it's coming in. And so the liver has a pop-off valve. It has a way of dealing with the excess. It turns that sugar into fat - liver fat. And we now know that it's that liver fat that drives all the chronic metabolic diseases that we have discussed, except for the tooth decay.

RAZ: So what is the - what is a daily recommended limit for, like, an adult human for maximum amount of sugar we should be having every day?

LUSTIG: Well, depends on who you ask. The World Health Organization originally said six teaspoons of added sugar per day.

RAZ: Sounds reasonable.

LUSTIG: Well, it is actually reasonable. It's 25 grams. It's not, you know, an enormous amount, but it should be enough. But - but they were lobbied so severely by the industry. So they actually ended up liberalizing it from 6 to 12 teaspoons of added sugar per day.

RAZ: OK, so 12 teaspoons a day, that sounds like a lot. Like, I can't imagine - what is the average amount sugar that an American or somebody in the West consumes every day?

LUSTIG: We are now at 19.5. So, you know, we are consuming about 50-percent more on average than our upper limit.

RAZ: Right.

LUSTIG: Now, there are some people who are consuming 30, 40, 50 teaspoons of added sugar per day. So we've been sort of upping our sugar ante for many, many years. And, of course, that's why Type 2 diabetes first became a huge problem in the 1920s and heart disease in the 1930s. And then something happened in the 1980s. High-fructose corn syrup happened.

RAZ: So is - is corn syrup, high-fructose corn syrup worse than cane sugar?

LUSTIG: It's cheaper.

RAZ: But they're both equally bad?

LUSTIG: Yeah, they're both equally bad. But if it's cheaper, then it's worse. And what that does is it also makes sugar cheaper because of the competition. Plus, that was exactly at the same time the low-fat directive came out of the USDA and the FDA - 1977, the first dietary goals for Americans said eat less fat.

Well, if you eat less fat, the food tastes like cardboard. The food industry knew that, so what'd they do? They pumped in the sugar. And now high-fructose corn syrup was cheaper, so they could do it.

RAZ: Wow.

LUSTIG: So let me give you an example how this works, OK? My favorite product of all time, Lucky Charms.

RAZ: Yeah.

LUSTIG: They're magically delicious.

RAZ: They are.

LUSTIG: Right?

LUSTIG: Why are there marshmallows in the box?

RAZ: 'Cause they're delicious? Secondary.

LUSTIG: Why are there marshmallows in the box?

RAZ: 'Cause they're fun to eat?

LUSTIG: Because marshmallows are cheap and oats are expensive. They take up more room in the box and they can sell them for more.

RAZ: Wow.

LUSTIG: Great business strategy.


LUSTIG: So everyone says education - educate the public, educate the populace, tell them what's going on, except for one thing, education hasn't worked for any other substance of abuse. Did Nancy Reagan's Just Say No work?


LUSTIG: Really? So where does that leave us? Everyone says wait a second. Don't tell me what to eat. Well, you know what? You've already been told what to eat. Where were you for the last 40 years as your food supply was being changed under your nose? Were you protesting then?

Everyone says, get government out of my kitchen. You know, I don't want government in my kitchen either unless there's somebody more dangerous already there, OK? So the real question is who the hell do you want in your kitchen? The government, who will take your freedom and your wallet, or the food industry, who's already taken your freedom, your wallet and your health? That's your only choice.


RAZ: So, I mean, given that choice, what do we do?

LUSTIG: Ultimately, we have to figure out how the food industry can still make money selling real food. And the answer is can they? Absolutely, they can, but not with the current business model.

The food industry grosses $1 trillion a year in the United States. Of that, $450 billion of it is gross profit. Now, health care costs in America total $2.7 trillion a year of which 75 percent is chronic metabolic disease, of which 75 percent of that could be preventable if we would do something about our diet. That's $1.4 trillion, triple what the food industry makes.

We spend triple cleaning up the food industry's mess than they actually make. The bottom line is they're going to drive this bus till the wheels fall off. The only answer is real food. We just have to figure out how to make it available and profitable for everyone.

RAZ: By the way, I'm assuming the sugar industry must really hate you?

LUSTIG: Sure, yeah.

RAZ: They hate you.

LUSTIG: (Laughter) In 10 words or less, yeah, they loathe me. That's the way this works. My job is to provide the science so that the public can make its own informed decision, and then...

RAZ: But not many people are saying what you're saying. I mean...

LUSTIG: Well, you know, look, there's a lot of noise in the system for obvious reasons. You've got all of these - this cacophony of people with their own vested interests. I have no vested interest other than taking care of children and seeing children get to adulthood to have a decent chance in life. That's my vested interest. And to be honest with you, it ought to be everybody's vested interest.

RAZ: So are you just, like, totally anti-sugar, or do you - like, do you indulge, you know, just a little bit?

LUSTIG: Of course, now and again. The problem is I'm for dessert.

RAZ: Yeah.

LUSTIG: For dessert.

RAZ: Right.

LUSTIG: But if you're going to have breakfast cereal with orange juice and a Capri Sun a granola bar - and that's all before 3 o'clock - you know, then you've got a problem.


RAZ: Robert Lustig is a professor at the University of California in San Francisco. You can see his entire talk at We're back in just a minute. Stay with us. On the show today, Ideas About How We Connect To Food. I'm Guy Raz, and you're listening to the TED Radio Hour from NPR.


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