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DR CHRIS VAN TULLEKEN: We need health warnings on ultraprocessed food!

A year ago, I managed to persuade my identical twin brother, Xand, to forgo ultra-processed foods (UPFs) such as pizza, ready meals, chips and chocolate, which had been his diet for many years so heavy and unhealthy.

UPFs are essentially industrially produced foods filled with sugar, fats and strange chemical ingredients not found in a normal home kitchen.

At some point, Xand turned 19 and that bothered me – not because I cared what he looked like, but because I was worried about what it would do to him in the long run – that he would die, leaving me miserable live without him.

So I put him on a nauseating binge eating diet with 80 percent UPFs for a week, while he spoke to experts about how such products can be addictive and lead to obesity.

What Xand underwent was a form of intensive aversion therapy — and it worked well: After just four days, he found it nearly impossible to eat UPFs.

On the anniversary of that experiment, I met my brother on a new podcast just before his usual dinner time. I had broken my habit of nagging him about his weight, but I wanted to see if he could be tempted.

At one point Xand (pictured left) hit the 19th and that bothered me (Chris Van Tulleken is pictured right) - not because I cared what he looked like, but because I was concerned about what it would look like on the long term to him - that he would die, leaving me to live miserable without him

At one point Xand (pictured left) hit the 19th and that bothered me (Chris Van Tulleken is pictured right) – not because I cared what he looked like, but because I was concerned about what it would look like on the long term to him – that he would die, leaving me to live miserable without him

I tried to tempt him with cookies and chocolate. He threw the packages across the room in disgust. A year ago, Xand would have eaten all of those – followed by a takeaway. This “disgust” wasn’t just for show either. The contents of his fridge and kitchen cupboards have changed.

Tellingly, one of Xand’s big UPF moments was his flights to Canada to see his teenage son Julian. But instead of the usual airport binge – stocking up on chips and sandwiches – on his most recent trip, he filled two plastic containers with a cut block of cheese and some apples. Even I was impressed. Xand also looks and seems noticeably healthier.

This was a huge success. But Xand isn’t the only one whose life has changed since he researched UPFs with me.

Last year, for our BBC podcast, I had consulted Alasdair Cant, a behavior change expert from Cambridge, who explained to me that I had to stop blaming Xand for his pompous ways, because I caused a state of confrontation where neither of us would give in – and this kept Xand from making changes to get healthier.

On the advice of Alasdair, I completely changed my mind. I just gave Xand all the available scientific information about UPFs so he could make a decision.

I know from personal experience how hard it is to give up UPFs – and then reverse the effects on your body. Last year, for a BBC documentary, I also lived on an 80 percent UPF diet for a month.

As extreme as it sounds, my UPF diet (and Xand’s) is what one in five Britons consume every day – and research shows conclusively that it’s the leading cause of obesity in this country.

After a month my 6ft frame exploded: I went from my normal 13 st to 14 st. Weight has gradually decreased by avoiding UPFs but over a year later I am still around 13 st 5 lb.

I’m constantly reading claims that all you need to do to lose weight is to stop eating UPFs, but it’s not that easy – not least because of the damage these foods can do.

As extreme as it sounds, my UPF diet (and Xand's) is what one in five Britons consume every day - and research shows conclusively that it's the leading cause of obesity in this country.  Xand is on the left in the photo while his brother Chris Van Tulleken is on the right

As extreme as it sounds, my UPF diet (and Xand's) is what one in five Britons consume every day - and research shows conclusively that it's the leading cause of obesity in this country.  Xand is on the left in the photo while his brother Chris Van Tulleken is on the right

As extreme as it sounds, my UPF diet (and Xand’s) is what one in five Britons consume every day – and research shows conclusively that it’s the leading cause of obesity in this country. Xand is on the left in the photo while his brother Chris Van Tulleken is on the right

Disturbingly, during my experiment, my brain started to become addicted to UPFs. An MRI scan showed an increase in connections between the reward center and areas that trigger repetitive, thoughtless behavior in just one month.

Essentially, I had become wired for food cravings and mindless consumption; my brain told me to eat UPFs without even wanting them. When we repeated the MRI scan three months later, those addictive brain changes were still there.

Results like this made me physically disgusted by the changes UPFs were making to me, and morally disgusted that people are actively selling this stuff for financial gain.

Disgust is a powerful instinct. So potent it stopped Xand and I from eating UPFs.

Professor Barry Smith, a sensory expert at the University of London, helped me with Xand’s experiment a year ago. He had previously advised food manufacturers on how to make their ultra-processed products more appealing – looking at crunch, aromas and flavors. He can’t tell you much about the specifics of his work, but did you know that ice cream bars have chocolate and caramel perfumes added to them because the ice cream itself is too cold to smell, but the companies want you to have a sensory hit right now. you take them out?

Since the podcast, Barry has also had a “conversion” experience.

“I try to avoid UPFs,” he said. “And I don’t want to work with companies that make things like this” — which meant cutting income. Without his expertise, it’s harder for ultra-processed food companies to fool us through packaging, taste and smell.

A year ago, I managed to persuade my identical twin brother, Xand, to do away with ultra-processed foods (UPFs) like pizza, ready meals, chips and chocolate, which had been his diet for years so heavy and unhealthy.

A year ago, I managed to persuade my identical twin brother, Xand, to do away with ultra-processed foods (UPFs) like pizza, ready meals, chips and chocolate, which had been his diet for years so heavy and unhealthy.

A year ago, I managed to persuade my identical twin brother, Xand, to do away with ultra-processed foods (UPFs) like pizza, ready meals, chips and chocolate, which had been his diet for years so heavy and unhealthy.

Meanwhile, Professor Rachel Batterham, head of the Center for Obesity Research at University College London, who performed my MRI scan, has focused her research on the damage of UPFs.

Like many, she had never heard of UPFs until our experiment. A year later, Rachel said, “Thanks to the podcast and the documentary, both my kids know about UPFs and both want to cook from scratch, even though such foods are not banned at home.”

The results of my experiment have also changed her research. Earlier this year, she published a paper in the journal Nutrients reviewing more than 430 studies on the topic and drawing troubling conclusions. It showed that UPFs themselves are major causes of obesity – and not (as the industry has consistently claimed) that people who eat these foods and gain weight have poor lifestyle habits.

UPFs are ubiquitous. Even our schools are pushing them, with research last month from Imperial College London showing they provide more than three quarters of the calories in high school lunches.

Given my strong sense of UPFs, you might expect me to call out product taxes. But as a public health physician, I think they would be unfair because UPFs are primarily targeted and consumed by low-income people. Advertising bans would be good, though – there’s no justification for selling these foods to children. The companies will not go bankrupt. People have a right to the information to give them the freedom to choose for themselves.

What people need is for food to be better labeled so that they know what they are eating and how it harms their health.

UPFs can look quite healthy under current labeling systems – which say nothing about food processing. For example, a soy vegetarian “sausage” may be low in fat, but is a UPF thanks to flavors, dyes, preservatives, and other chemicals that disrupt appetite and damage our bodies.

The fact is, we still have some UPFs even in my own house. If I completely forbid them from my kids, Lyra, five, and Sasha, two, they’d want to eat even more of them.

However, I buy less UPFs and try to tell Lyra that they are bad for her. (In fact, she says her “favorite food is ultra-processed foods and pasta,” so there’s still a way to go.)

I wish UPFs would become more like cigarettes in terms of the warnings on them, especially as we are becoming more and more confident that the damage is comparable. That does not mean that we should ban them, but that we should ensure that everyone has access to information and to affordable, high-quality food. In that regard, we still have a long way to go in this country.

All this requires understanding and compassion. People still think obesity is due to a lack of activity and willpower, but there is no science to back it up.

Many who live with obesity have lost a huge amount of weight many times over. But sustaining weight loss is like trying to quit smoking in the 1950s: almost impossible when you’re surrounded by a deluge of ultra-processed foods and marketing.

As I discovered with my brother, whining is of no use. If we want to prevent children from being just as badly affected, we need to drastically change their food environment and limit the ability of the companies that sell our food to take advantage of ill health.

An In-Depth Investigation with Drs Chris and Xand: One Year On is on BBC Sounds.

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