• The Listener
  • North & South
  • Noted
  • RNZ
Getty Images/Listener illustration

Binge brain: The latest science on how to beat your brain's reaction to sugar and fat

Ultra-processed foods that combine sugar, fat, salt and refined carbs in a way not found in nature have a hold as powerful as heroin over growing numbers of us.

Food had taken over *Jane’s life. A damaging cycle of dieting and bingeing led to weight gain, high blood pressure and high cholesterol. But the physical effect of her eating disorder wasn’t what bothered her most; it was the way it messed with her mind.

“All I could think about was food,” she says. “It took over my life. I wanted my fix like a drug addict and I’d go to any lengths to get it.”

Sugary foods and breads were her cravings, and once she started eating them, it was impossible to stop. It didn’t help that Jane worked in the food industry.

“There were foods that would trigger me, like chocolate and peanut butter,” she recalls. “Then, once I got a sugar or flour hit, it would send me into a frenzy. I tried everything, from a lifetime of counselling to Weight Watchers. I was miserable and hated myself. Then I had a horrific binge that really scared me.”

Read more: A young woman opens up about binge-eating disorder | How to overcome binge-eating urges

Her salvation was Food Addicts In Recovery Anonymous (FA), an international organisation that holds regular meetings in just two places in New Zealand, Wellington and Porirua. Like Alcoholics Anonymous, it has a 12-step programme. It defines abstinence as weighed and measured meals with nothing in between, no flour or sugar and the avoidance of any individual binge foods.

You don’t have to be a binger or even overweight to identify as a food addict. Undereating, bulimia and an extreme obsession with eating are among the symptoms. The FA philosophy is that when we abuse food as a drug, our lives become unmanageable.

“When I heard the words ‘food addict’ it was such a relief to know what was wrong with me. It was one of those light-bulb moments,” says Jane.

That was six years ago, and now, in her early fifties, she is managing her addiction. “For the first time in my life I’m completely clean, and it’s such a relief. I feel so much calmer and clearer. My food is simple, my life is simple and it’s one day at a time, so it’s not overwhelming. When I go to bed I’m a food addict and when I wake up I’m a food addict; I’ve just got to get through that day.”

Food addiction is controversial in the scientific community, where it isn’t fully recognised. One of the pioneers working to change that is Ashley Gearhardt. Ten years ago, she devised the Yale Food Addiction Scale (YFAS), the first measure to assess signs of addictive-like eating behaviour.

Gearhardt, an associate professor in the University of Michigan’s department of psychology, has a lab designed to look like a fast-food restaurant and her work is contributing to a new realisation that what we have done to food in the past 40 years has turned it into a powerfully addictive substance.

*Name changed to protect anonymity.

Yale Food Addiction Scale creator Ashley Gearhardt.

Pass the dopamine

Not all foods are created equal, says Gearhardt. Some are particularly effective at engaging the brain’s dopamine-producing reward system. These are the ultra-processed foods combining sugar, fat, salt and refined carbs in a way that isn’t found in naturally occurring food sources. Our brain simply isn’t equipped to cope with these products. In fact, it evolved to help us through scarcity by priming us to want exactly these sorts of high-calorie snacks.

“It used to be that the best source of sugar we had in the natural environment was a berry or some honey that we had to scale a tree and fight bees off to get, so it was rare and not that intense,” says Gearhardt. “Because we’re designed to seek them for survival, it doesn’t take much for these foods to be engineered in a way that makes the reward systems go awry. They affect the same systems of the brain that drugs of abuse hijack, to drive forward addictive behaviour.”

Work by other researchers has demonstrated the effect ultra-processed food has on the brains of animals. A study by Florida scientists Paul Kenny and Paul Johnson showed that when rats were fed a diet of junk food, they became so hooked that when it was taken away and replaced with a healthy meal, the rodents chose to starve. However, those rats were driven to eat cheesecake, bacon and sausage even when they knew doing so would result in them being given an electric shock to their feet.

Paul Kenny. Photo/Supplied

People don’t tend to get addicted to kale, broccoli or beans, says Gearhardt. Even fruits such as bananas, strawberries and apples are unlikely to lead to compulsive behaviour, perhaps because the natural sugars they contain are released more slowly in the body. The foods that are most tied in with addiction markers are, predictably, chocolate, ice cream, chips, cookies, crisps, cake, popcorn, cheeseburgers and muffins.

Just like cocaine, cigarettes or alcohol, you can start to crave these ultra-processed treats. Gearhardt has shown that looking at a chocolate milkshake activates parts of the brain that are associated with motivation, desire and drive far more than looking at a glass of water. The 15% of people who become clinically addicted are overwhelmed by cravings, need more and more to feel satisfied, keep consuming even when it is doing them harm, experience withdrawal when trying to cut down and spend a great deal of time acquiring, using or recovering from their drug of choice.

“We didn’t used to see this addictive behaviour towards food in the way we do now and that’s because foods weren’t as powerful or as accessible,” says Gearhardt. “Way back in history, the kings and queens of England, who had lots of access to sugar, exhibited signs of obsessive-compulsive consumption – look at King Henry VIII with his morbid obesity. Now, with industrialisation, we’ve kind of flipped things, and if you’re poor, these potentially addictive foods are more likely to be what you have access to.”

Ultra-processed foods aren’t only cheap and plentiful, they are what are mostly to be found in supermarkets. Each year, the University of Auckland collects data on the packaged foods available in shops, photographing the nutritional panels for analysis. This year, 13,000 different items were assessed for the New Zealand State of the Food Supply study. Two-thirds of these were found to be ultra-processed – high in sugar, salt or fat – and half were foods not necessary in a person’s diet.

Sally Mackay. Photo/Supplied

“That’s a lot of unhealthy products on our shelves,” says lead author Sally Mackay. She is calling for the Government to start setting targets for sodium and sugar levels in packaged products. She would also like to see the health-star rating put on all foods to make it easier for consumers to tell at a glance whether what they are buying is good or bad for them (the rating system introduced in 2014 is on only 20% of products). Mackay is also concerned at the marketing of food – the 2017 Kids’Cam study found children in New Zealand are exposed to 27 junk-food advertisements a day.

Many food manufacturers are unlikely to change without a prod and Gearhardt says the only solution on a population level is policy change.

“It is going to take big, wide-ranging policies to shift our food environment and that will be politically challenging. But from my perspective, we’re not going to have a choice eventually because the cost of diet-related diseases is going to overwhelm us,” she says. “We’ve done it before with tobacco, I think we can do it again.”

As with alcohol and other drugs, many of us can indulge in a few ultra-processed foods without developing a major problem. Finding solace in a tub of ice cream or a chocolate bar after a hard day’s work doesn’t necessarily put you on the road to ruin.

“What we find is that only 10-15% of people get addicted to even drugs as strong as heroin,” says Gearhardt, who adds that a number of factors are at play. “We know genetics plays a role. Having a lot of early-life stress and trauma can seem to prime the brain to addiction. If you were exposed to the drug of abuse when you were in the womb, that also sets you up to be at greater risk. We are seeing the same thing is probably true when we look at the population of people who seem to be showing an addiction to ultra-processed food. It’s really an interaction between your own personal risk factors and the drug or food.”

Gearhardt has concerns about the highly prescriptive Food Addicts In Recovery Anonymous approach, partly because there isn’t a lot of science to back it up and also because it may have the potential to create more disordered eating for some.

“For a relatively small group of people, abstaining from this whole class of foods might be the only option,” she says. “But for the majority, it is not going to require something nearly as extreme.”

In the field of addiction, there has been a big push towards harm-reduction approaches for mild to moderate substance disorders. And when it comes to food, all of us need to think about some harm reduction because we are all exposed to these foods and thus at risk of developing at least a mildly disordered approach to eating them.

On average, when people are tested against the YFAS, they show one or two symptoms of addiction.

“Even if you are not fully clinically addicted, but are hooked enough on these foods that you are eating an extra couple of hundred calories a day, that is sufficient for your weight to begin creeping up and for you to be at greater risk of diet-related disease,” says Gearhardt. “It doesn’t take a full-blown addiction to start to have negative consequences because of an addictive substance.”

Photo/Getty Images

Personal control

Gearhardt is a fan of taking control over your own personal food environment. That might mean getting rid of ultra-processed products and stocking the home and workplace with enjoyable naturally occurring foods such as strawberries or nuts.

“It’s best not to starve yourself,” she says, “because when we’re really hungry, the gut peptides that tell us we’re in need of calories prime the reward system of the brain that goes awry in addiction. I also suggest that people monitor what their triggers are out in the world. There are going to be external cues such as certain fast-food restaurants or vending machines, but also internal cues such as emotions or boredom. The more you equip yourself with this knowledge, the easier it is to go about your day and have a plan for when those things arise.”

Gearhardt isn’t preaching complete abstinence – she is fond of chocolate peanut Kind bars that are made and sold in the US. “But there might be foods that are super-high-risk for you – such as double chocolate chunk ice cream or salt and vinegar crisps. And there might be times when trying to eat a riskier food is going to set you up to fail, such as late at night or when you’ve had a stressful day and are really tired. If you can’t ever eat them in moderation, maybe it’s time to take a break from these foods, almost as if you have an allergy to them.”

It is especially difficult to negotiate the modern food environment if you are a parent. As the mother of a small son, Gearhardt empathises, and in her work she studies children at every developmental stage, including infants as young as two weeks, trying to understand the effect on the brain of exposure to sugar and ultra-processed foods in early life, when the reward systems are developing.

“You don’t want to make your child feel shame or fear about their eating, and yet we know that early childhood and adolescence is a time when they are establishing eating habits and are at high risk of obesity and even binge-eating disorders.”

There are many pathways to obesity, concedes Gearhardt, and our biological bias towards unhealthy junk food can’t be blamed for the entire problem. In fact, it is possible to have a body mass index (BMI) that is in the normal range and still show signs of addiction in your eating. And whereas some people binge-eat, others don’t have any loss of control. Instead, they do what Gearhardt describes as the equivalent of chain-smoking, dosing with a snack or sweet treat every couple of hours throughout the day.

We have a history of being slow off the mark when it comes to recognising addictive substances. For food addiction, it is still early days. However, the YFAS has been translated into more than 10 languages and cited several hundred times, so Gearhardt is confident it now has momentum.

“On the face of it, food does seem different. We all need to eat, it’s legal, it’s not intoxicating, and yet our over-consumption of these not-naturally-occurring, ultra-processed junk foods is one of the biggest killers in the world today,” she says.

Whereas the science community might be slow to recognise the problem, Gearhardt  says most ordinary people don’t need much convincing. “When I talk to people outside of this world, they’re like, ‘Are you kidding me? Why are you even researching this?”

Scale of the problem

The Yale Food Addiction Scale asks how frequently you have experienced any of the following in the past year:

  • I ate to the point where I felt physically ill.
  • I spent a lot of time feeling sluggish or tired from overeating.
  • I avoided work, school or social activities because I was afraid I would overeat there.
  • If I had emotional problems because I hadn’t eaten certain foods, I would eat those foods to feel better.
  • My eating behaviour caused me a lot of distress.
  • I had significant problems in my life because of food and eating. These may have been problems with my daily routine, work, school, friends, family or health.
  • My overeating got in the way of me taking care of my family or doing household chores.
  • I kept eating in the same way even though it caused me emotional problems.
  • Eating the same amount of food did not give me as much enjoyment as it used to.
  • I had such strong urges to eat certain foods that I couldn’t think of anything else.
  • I tried and failed to cut down on or stop eating certain foods.
  • I was so distracted by eating that I could have been hurt (for example, when driving the car, crossing the street, operating machinery).
  • My friends or family were worried about how much I overate.

This article was first published in the November 16, 2019 issue of the New Zealand Listener.