Just One More: The Cognitive Science Behind Our Sugar Addiction

“As far as sugar and flour are concerned, once you grind it up I don’t care what it’s made out of. You’ve turned it into a drug.”

Dr. Susan Peirce Thompson is a professor of brain and cognitive sciences at the University of Rochester, founder and CEO of Bright Line Eating Solutions, and the author of the New York Times best-selling book Bright Line Eating: The Science of Living Happy, Thin and Free. She joined Gary Taubes, an award-winning investigative journalist and the co-founder of the Nutrition Science Initiative, and bestselling author of The Case Against Sugar for a conversation on combatting our culture’s sugar addiction.

This conversation has been edited and condensed. View their full conversation on the video below.

Susan: I’m an addict. I pass for normal today, but I’m walking around with a head that’s ridiculously, outrageously susceptible to addiction, and my life has proved as much. I bottomed out on crystal meth and crack cocaine in my teenage years, [but] after I put down crack and got sober when I was 20, I became more hooked on sugar then I’d ever been hooked on anything in my life.

[I was] successful in every area of my life after I got clean, but I couldn’t stop eating raw cookie dough, pints of ice cream, pizza, pasta, bread.

Gary: [In] the first chapter of my book, I talked about [nutrition] research [that] is misleadingly ambiguous on sugar and drug addiction. I can speak from personal experience about whether and which is more addictive. You have this personal experience with 12 step programs—[is] it actually recommended in Alcoholics Anonymous [to] use sugar as a transition drug, a kind of “healthy” addiction?

Susan: Sugar helps the cravings, definitely. Sugar and alcohol are almost molecularly identical, except for the ethanol compound that’s going to make you intoxicated. And the nucleus accumbens want their dopamine hit, right? The hit [will come] from sex, or gambling, or shopping, or alcohol, sugar, cocaine, whatever. All of [these activities] are relatively interchangeable when you look at the nucleus accumbens. I have used substitute addictions, and sometimes felt like my stretch of perfect sobriety is largely due to the fact that I’ve had other things to use.

I have struggled on and off with sugar, and with flour during [my 22 years sober]. When I’m jonesing for a fix, I don’t need to go back to the crack pipe, because I can go get a cookie.

Gary: How do you avoid sugar? Because it’s in virtually every processed food.

Susan: I don’t eat processed shit. Really, I eat broccoli, and salad, yogurt, and oatmeal, and fruit, nuts and seeds. I eat real food. I don’t eat stuff that comes out of packages.

“I’m as hardcore about sugar as you are. I inform my discussion of it from my own addiction. I know that I would never try to smoke cigarettes in moderation, and I know that drinking coffee in moderation has failed me my whole life.”

Gary: What kind of fruit? I’m as hardcore about sugar as you are. I inform my discussion of it from my own addiction. I know that I would never try to smoke cigarettes in moderation, and I know that drinking coffee in moderation has failed me my whole life. [So], what about fruit? It’s a much smaller dose [of sugar]. It [takes] longer to digest—but it’s still sugar. There’s still fructose and sucrose.

Susan: Every piece of fruit has plenty of soluble and insoluble fiber. It makes this fiber lattice network that blunts the flood of the fructose into the digestive system. I always eat fruit with a meal.

If you’re going to eat fruit, eat it with a meal so you’ve got fat and protein to round out that glycemic load. For me, with a meal, one piece of fruit at breakfast and one piece of fruit at lunch is totally fine. In my Bright Line Eating Program, 20,000 people have lost 300,000 pounds over the last couple of years, and a bigger proportion of them are getting to [their] goal weight. We’re walking testimony to the idea that fruit with a meal, twice a day is actually fine. It doesn’t keep insulin from coming down.

Gary: This is where we come to this from different perspectives. I’m more of a [proponent of] getting insulin as low as possible, and the way to get insulin as low as possible is to replace all the non-green vegetable carbs with fat. As a journalist, I’m not allowed to give dietary advice, although it’s a thin line that I’ve always crossed because there are obvious implications from my books.

Susan: As far as sugar and flour are concerned, once you grind it up I don’t care what it’s made out of. You’ve turned it into a drug. You’ve just exponentially increased the surface area of each of those particles. Dr. Alan Christianson thinks of digestion as melting ice. A block of ice on the blacktop will take hours to melt. But, if you put snow cone shavings on a blacktop, it melts on contact. Once any kind of plant is ground down, digestive enzymes [can] have a field day with it.

“As far as sugar and flour are concerned, once you grind it up I don’t care what it’s made out of. You’ve turned it into a drug.”

Gary: No green juices, got it. How about potatoes? I would think the potatoes would be a mistake, but they are unrefined.

Susan: What I’ve found works is stripping out grains. Potatoes are in that category, even though biologically…

Gary: They’re not grains.

Susan: Yes. But we put them in there. You strip out grains during the weight loss phase, except for a tiny serving of grain at breakfast, which is usually oatmeal. Other than that, you strip out grains from lunch and dinner entirely, and eat protein, fat, vegetables, a serving of fruit at lunch.

Gary: This is an issue I discussed in my first book on bad calories. The medical community tends to frown, and rightfully so, on anecdotal evidence. If you admit that your thinking was shaped by your own experience that somehow makes you biased.

The absence of curiosity is then considered a stamp of expertise, and I’ve never quite understood that as well. But a criticism of your work would be, “It might have worked for her, but that doesn’t mean it works for everyone.”

Susan: What we have for the first time in human history in Bright Line Eating is a model of actually taking a cohort of people, overweight or obese, getting them down to goal weight and then helping them to stay there for some period of time. It’s never been done before in the scientific literature. There’s not a single published paper.

We’ve done it, and that’s the first model of effective weight loss that’s ever existed. Weight Watchers gets people to lose 10, 15 pounds on average—in six months, they start gaining back. I’m sure there’ll be plenty of detractors, but I’m going to be feisty about it, because I think we’re showing something pretty exciting.

Gary: The argument I’ve been making over the years is that because our understanding of obesity and how to achieve weight loss has been so flawed, all these programs rely on some variation of getting people to eat less and exercise more. This is based on what I think is a flawed paradigm.

My argument has been: these carbohydrates, the same carbs you’d target as uniquely addictive, I would target as uniquely fattening. Any diet will work that removes them. Then the question is what’s sustainable and what’s most effective at removing them.

When people fail on your approach, do you know why they fail? Because there are other hormones involved in fueling fat accumulation. Women, in particular, as they get older and go through menopause, are going to have more trouble losing weight regardless of what they do.

Susan: We have data on that, actually. Across a couple thousand women, on average, people lose 17 pounds in an eight week boot camp with us, and the highest peaks of weight loss are during the decades of the 20s and the 50s for women.

Gary: 20s and 50s?

Susan: Yes, with 18.5 pounds on average lost in the boot camp. In their 60s and 70s, those numbers go down to 17 pounds, and then 15.8 pounds. In their 70s, women are losing 15.8 pounds in eight weeks in my boot camp, almost not significantly different from women in their 20s and 30s.

We’re not seeing a huge age effect, but your question is well-framed. Here’s another statistic: 84% of people coming out of the boot camp report little to no food cravings anymore—ever. You get sugar and flour out of their system for a week, and they’re reporting little to no cravings.

“The medical community tends to frown on anecdotal evidence. If you admit that your thinking was shaped by your own experience that somehow makes you biased. The absence of curiosity is then considered a stamp of expertise.”

Gary: That’s where I think [sugar] is different than nicotine, and probably crack cocaine. For me, out of sight is out of mind with sugar. With cigarettes, it didn’t matter how out of sight it was. When I was trying to quit, it took me weeks and weeks and weeks to stop actively craving. My neurons were anxiously awaiting their next hit. On some level, there have to be different types of addictions, or at least different qualitatively. Something different is going on.

Susan: Maybe. I don’t know if people are wired for a primary addiction. I think there are plenty of people for whom the sugar keeps calling. I said 84%—there’s 16% that are not experiencing it. We haven’t looked at their brains, or their blood, or anything to see what might be going on there. I think there’s a lot of individual differences. I wonder if there’s something in the blood or in the brain of a person that predisposes them to not be successful, if their bodies are fighting them somehow.

Gary: I get this question a lot: “How do I deal with sugar cravings?” Since I’m one of these people who thinks butter and bacon are health foods, [I believe that] if you jack up the fat content of the diet, it’ll reduce the craving for carbohydrates in general.

Susan: You wrote an article that I love exonerating salt. Salt is not only fine, it’s necessary, and it’s way worse to cut salt out of your diet entirely than it is to eat too much salt. People don’t actually eat too much salt if you leave them alone.

Gary: If you’re targeting sugar and flour, what do you have left to make the food taste good? The research that led me into this entire field was the salt and blood-pressure question. Obesity, diabetes, and heart disease are all hypertensive conditions. Whatever is causing the hypertension in those conditions is likely causing the hypertension even before those conditions show up. High blood pressure’s a part of metabolic syndrome, so you’re looking at what’s raising insulin. What’s causing insulin resistance? That’s going to be a sugar and flour issue. It’s not going to be a salt issue.

One of the arguments I’ve been making for years as an investigative journalist is that nutritional researchers didn’t know how to do science. They got an idea, an interesting hypothesis [and] fell in love with it. No matter how many studies failed to confirm their hypothesis, they just insisted they must be right, and the presumed link between salt and hypertensive conditions was one of them. Dietary fat was one of [these hypotheses] too, and the idea that we get fat just because we eat too many calories was the mother of all of them.

We’re slowly shedding all of these, but it’s a very slow process. Once institutions embrace them, when you start getting advice from the American Heart Association and the NIH to eat less salt, it’s hard for them to backpedal.

Susan: I got people to clean up their diet, and then they’d come to me and say, “I’m dizzy.”

Gary: Because their blood pressure is too low.

“You’ll eat 11% more broccoli if you put some butter and salt on it, but nobody’s driving out into the night to get some buttered, salted broccoli.”

Susan: I say, “Do you add salt to your food?” Because they had some doctor a long time ago when they had high blood pressure tell them to cut out salt, which was the only thing they could effectively do because salt is not addictive. The addictive foods are sugar and flour, and salt makes food more palatable. Yeah, you’ll eat a little more of it. You’ll eat 11% more broccoli if you put some butter and salt on it, but nobody’s driving out into the night to get some buttered, salted broccoli. They’re going for a chocolate bar, they’re going for ice cream, they’re going for pizza. It’s the sugar and flour.

Gary: [People] are getting the wrong advice. Their belief system is diets don’t work, and we know diets don’t work because we do these terrible free living diet studies, and at the end of the year, people have only lost six pounds. Therefore, we can just work on our drug development, and we can get funding from the pharmaceutical industry, and the drug industry can make a lot of money, and we can keep telling people it doesn’t really matter what you eat. Let us treat it with drugs, everyone’s happy. A whole mindset that targets drug therapy instead of prevention, instead of successful dietary therapy.

Susan: Do you think that we’re on the precipice of a real change? Do you think people are starting to get how bad sugar is?

Gary: Yes. If you look at sugar consumption, it’s been coming down since 1999. Soft drink consumption has been coming down. That’s when it peaked. As soon as we recognized there’s an obesity epidemic, some people started looking around to see what was causing it. A lot of people just assumed it was gluttony and sloth, but it’s been coming steadily down, and I think that your work, and my work, and others have shifted how people think about those foods. Less about moderation and more about thinking about how to avoid it. I think with sugar, we’re winning.