Is ultra-processed food really that bad for us?

So I do the upsiders. I would encourage anybody to, if they haven't done a roady for a while, to just go out and look at the absolute beauty that we have outside of our main centers.

got their driver's license, so now they are independent. You know, you're no longer driving them to dance classes and various other things. So it's quite exciting. But there's so much time in the day. I am a little bit taken back at how much time there is in the day which I can now work and be productive and do things, which.

actually a substantial period of time, thirteen years each. You've got three kids like you you're doing it for.

in his mid forties with five children. My goodness, my brother also found himself for whatever, and I have friends who are widows, and I just think it is something we we ought to address because we're going to know somebody or it's going to happen to us or whatever. I just think it's another area that we should touch on, not in a super doomy, gloomy way. You know, there's some there's some recovery and joy and the process. I'm also keen to talk about some less serious topics, like

what the heck's going on with everybody going skinny? That's a bit weird.

ultra process foods, what you should and shouldn't be eating. Yeah, I mean, neither of us are into dieting, and we believe your diet can't be perfect all the time, but we are interested in having a clearer picture of how to eat for our health and what we should be more mindful of consuming. So you know, when it comes to process and ultra process food, what's okay and what should we actively avoid.

in previous episodes. Definitely with the listen. Sarah is at the forefront of developments and personal nutrition and has been in charge of some of the world's largest human nutrition studies. Her work explores how foods impact metabolism, fat storage, and long term health. And doctor Sarah Berry is with us. Thank you so much for joining us.

form of processing because you've cooked them. But in the current food landscape that we live in, we are actually used the term very differently, and we typically use it in the context of a classification system called the NOVA classification system, which allocates a classifier according to whether it's unprocessed, minimally processed. A processed culinary ingredient like a sort of spice or something, or oil or something that's called an ultra processed food, And an ultra processed food is a

classification system from this system called NOVA. It's a NOVA for food. But it's a term that's really taken off because it's been used in a lot of nutrition research in order to class apply foods that have been heavily processed. But I think what's really really important to remember in

the whole discussion of ultra process food. And when we look at the evidence and we look at these scary headlines that are often out there about food processing, is the term ultraprocessed food is specific to this classification system, and this classification system is based on the extent and the purpose of processing is a system that was never designed to look at how processing might impact our health.

And so we see, for example, in the UK, the US, Australia is becoming quite similar in New Zealand as well, that about sixty percent of our food comes from this ultra process food. But it's such a huge category, and you have within this category of or classification of ultra process food some that, yes, are really bad, but some

that aren't so bad. So I think we kind of need to take a step back and think, really, what is set about food processing that's bad in order for us to identify what we should be avoiding and what we shouldn't be avoiding.

lot cheaper. And there's some fantastic research that was recently published showing that if you look at all of the food that are in US supermarkets, what you see is an ultra processed or heavily processed version versus a minimally processed version has about a fifty percent price differential, meaning, for example, if you take a bread that a minimally processed, more kind of Artisian style bread is actually about fifty percent more expensive than one of the mass produced breads

that would be classed as ultra process And they saw this across all of the different food groups, whether it was yogurts, whether it's pastries, whether it's meat based products, etc. So we do need to be mindful that again in this kind of demonization of ultra process food, in this scare mongering that you see out there, that processing does have a really important purpose and it does enable us to also consume food that is more affordable for many people.

So what we need to do is work on identifying which of those foods are particularly bad for us, because our research that we've done at Zoe actually shows that it's probably only about twenty percent of our energy that's coming from processed foods that we know are particularly unfavorable for our health.

processed that makes it unhealthy. But it's really really difficult, and it's really difficult because processing impacts the healthfulness of food, not just through the additives and emulsifiers that everyone's talking about, but actually through lots of other mechanisms. So we know that when you process food, and there's lots of different ways we can process food, whether it's through heat processes, whether it's through physical disruption of the food structure, whether

it's through predigesting the food. You know, there's so many different ways that you can process the food. But what we know is that impacts certain features that are related to health. Firstly, we know that typically heavily processed foods tends to have less nutritious nutrients or less healthy nutrients. By this, it tends to have less fiber, it tends to have more unhealthy nutrients, so it tends to have more salt, more saturated fat, more sugar. It also tends

to have less bioactives. And these are chemicals that are found in foods that we know have really magical properties in improving our health. So you might have heard a polyph phenols for example, it comes from dark figmented pigmented berries, you know, and these have really fantastic properties in terms of you know, acting on anti inflammatory pathways and so forth. So processed foods tend to have less of those bioactives

as well, they tend to have less nutritious nutrients. Then they do tend to have lots of additives, lots of emulsifiers. So yes, you can look at the back of pack and you can look at two foods and you could say, whoa, hold on, here's a peanut butter. Here's one that just literally has peanuts, maybe a pinch of salt and a pinch of sugar. And then here's a peanut butter like in the America, for example, as Reese's peanut butter, which unfortunately my kids love. You know, yes, it's got about

thirty ingredients. It's got loads of E numbers, which are basically numbers that are allocated to emulsifiers and additives. So that gives you a good hint that hold on, maybe that's not so healthy. But in my opinion, that's only part of the picture, and that we need to look at other features. One of those features is hyperpalatability, which

is basically how tasty that food is. And another feature is the food structure, the food matrix, which is destroyed in processing, which impacts how fast you eat that food, where the nutrients are absorbed, how much of the nutrients you're absorbed in.

we know bypass our natural physiological, neurological responses. So these are foods that will be particularly high in maybe salt and sugar, or salt and fat, or fat and sugar that you wouldn't typically find in nature. So let's take crisps for example. Crisps have a reasonable amount of fat and they have a reasonable amount of salt. Now, you wouldn't typically find that same amount of salt and that same amount of fat in a natural product that's not

naturally in the potatoes. But by putting them together, it's almost kind of like bypasses our natural sensory system that tells us, well, hold on, you've eaten enough, you don't need anymore. Instead, what it's doing is activating the reward system in our brain, a bit like giving us some kind of mini dopamine hits and saying, oh my god, this is so tasty. Keep eating, keep eating, keep eating, so that you tend to over eat hyper palatable foods.

And there's quite a bit of evidence showing that, yes, you tend to overeat them, and people that have more of these hyper palatable foods put on more weight. And so I think that's one really interesting area where you know, we're now so accustomed to having these foods that what do we do, How do we go back to experiencing pleasure from that potato, for example, without all of that salt? And there are studies showing that yes, you can retrain

your taste fuds, et cetera. But what's difficult is when you go into your supermarket, when you go to your corner shop or your high street and everything there or what we know in the UK and the US, for example, is about sixty percent and I don't know in that their stats in New Zealand, but sixty percent of the

food is probably hyper palatable. And so when you're faced with all of this, it's really difficult to make those healthy choices and think, oh my gosh, I know that's tasty, but hey, let me try and find something that's less tasty, because I know it's for healthy. I can't be that good. I tell you what, when I have my wine after this, I'll be some nice salt and vinegar crisps with it.

of all of these different chronic diseases. But I think what we need to be mindful of is the evidence is typically coming from either these longitudinal studies or cross sexual studies where you take large populations, you follow them over a period of time, you look at what their diet is at you know, maybe five ten year intervals, and then you look who goes on to get what type of disease. Now, that's a really important way that we get a first hint of what's going on in

terms of diet and in terms of disease. But for that kind of research, we typically use food frequency questionnaires, which asks quite crude questions. So it would ask, for example, do you have peanut butter or not. It wouldn't say do you have recess peanut butter or this healthy peanut butter. It can't differentiate between brands. So yes, there is data to show the old process food at linked with health.

But what we now know is that not all ultra processed foods are linked in the same way and to the same degree. And so there is some research that's broken down quite crude categories that you can still do through food frequency questionnaires that show that if you look at the link between old processed food intaken an individual and their risk of all course mortality basically meaning death, that yes, as your old process foodn't take increases, so

does your risk of death. And it's largely attributable if you look at the different food groups to an increase in red process meat and in sugar sweetened and artificially sweetened beverages. What you see, conversely, is that cereal products. Now I know, seal products are really a big range.

They could be everything from your terrible sugary you know, kid cereals that you see in supermarket right through to a healthy whole grain, but they're actually associated with a reduced risk of all course mortality even if they're classified a sultra process. So I think we need to be a bit careful demonizing everything because yes, overall it shows there's a problem, but actually not all ultra processed food

is created equally. And then within each of those food groups I've mentioned earlier, even within those groups, whether it's cereals, whether it's you know, even process red meat, we know

that there's a huge variability. You know, if you look at the food group of cereals, you've got everything from those awful sugary cereals that again unfortunately my kids love right through to some very healthy cereals, but would still be classed as ultra process And so this, I think is what makes it challenging, and this is why I think we have to be a little bit careful getting too scared by the stats that you see that say, you know, our diet sixty percent ultra process. You know,

what are we going to do? We cannot change our diet that radically in the food landscape that we live in if we are that average person getting sixty percent of our energy from ultra processed food. And that's why again we've really got to focus on which ones are really bad for us and which ones aren't. And I'm sorry that I'm not giving you a list of rand level foods in New Zealand that are the really bad ones.

oh my gosh, it's got so many different ingredients. It's got all of these additives and a master piers and then you've got, for example, in the UK, I don't know if you have it, there a peanut butter called pipper nut. That's just a very unprocess. It's just nuts, ground nuts and salt so yes that gives you an indication, But what that doesn't tell us is the hyperpalatability that

I mentioned. But it also doesn't tell us what I think is one of the most important features alongside the nutritional composition, of why processing can impact our health, and that's the food structure. That when you process a food in many instances, you change the food structure or what we in science call the food matrix, and that has a big impact in terms of how it impacts our health,

how it impacts our metabolism, and so much more. And that's why it's really challenging, I think, because you cannot on the back of pack label say this is a good food structure, that's a bad food structure. Yes, we can help people identify has the structure been changed such way it may negatively impact our health. And there's really simple ways. Does that food look like the food from which it originally came or does it not resemble that

original food? And there's simple examples that I often use when I teach about this from my own research, an old research as well, and there's this lovely study that was carried out many years ago, actually even before processing was the big issue that it is now, and This was a study in nineteen seventy seven where they fed people whole apples, or they literally puraid those apples. So imagine just making it into a smoothie so it had exactly the same ingredients. All you had done was change

the structure. You just mushed it up basically. And then they fed people apple juice where they'd actually taken out some of the fiber. But the important comparison is the apples and the apple pure, because the backuppack labeling would show that they're identical. If they were in a supermarket and they fed these individuals apple pure and apples, they had fifty grams of available carbohydrate, they're identical. What they found was there was a massive difference, about tenfold difference

in terms of how quickly people eat them. You could eat the pure so much more quickly. And what they found was even when the invited individuals back and said, okay, I want you to actually eat it at the same time, so we remove this problem of the fact that you're eating the pure faster, they found that there was a big difference in terms of how full they felt after. So after the apples they felt about fifty percent more full compared to the apple pure, but it was the

same food, just change the texture and the structure. Then they looked at the post pant or glucose response, which is basically the post meal increase in circulating blood glucose from the sugar from the carbohydrate in the apples and the pure, and what they found was a big difference in terms of about two to four hours after consuming the pure, people had a big dip in their glucose

below baseline compared to the apples. And what this means is when you have a dip, it drives your body to want to quickly eat food because your body is thinking, oh my god, I'm going into a hypergodallysimic shock, which you're not. It's just a dip in your glucose. And what we've seen from our own Zoe predict research is this dip is associated with people then going on to consume three hundred and twenty calories more over a day

compared to if they don't have a dip. So what you've got happening here is you've got this apple, you've got the pure A backupack labelings are same, no difference in emulsifiers, additives, nutrients, etc. But you're eating, they're at a very different rate, You're having a very different fullness response, You're having a very different glucose metabolic response that's causing this dip that we believe will therefore cause you to overeat.

And this study is lovely because we've since done many studies that have really replicated this, and you know, lots of other foods, except that just show how important that structural integrity is, whereas the texture of a food is.

that it's full. Many processed foods are also processed in such a way that by breaking up the structure, they're absorbed a lot more quickly, so you have this bigger peek and then this dip in glucose, and this dip in glucose causes this feeling of hunger, but also it changes where you absorb them as well, in your gut. And so what we know is that food that tends to have the matrix more preserved tends to be absorbed

lower down the gastrointestinal tract. And what's relevant here is lower down your gastro intestinal tract you have more fullness receptors, so more GLP one receptors. You probably all heard of

GLP one. You know, this is the the you know, the different drugs that are out there, like a zenpic will go v And so if you're absorbing these very mushed up foods because of how they've been processed higher up the gastro intestinal tracked, they don't have quite so many GLP receptors, so you're not feeling it's so full yet if it's absorbed more slowly because the matrix the structure of food is slowing it down, then you're also going to feel more full because of that.

don't talk enough about is eating rate. And I think this is really important because this is something that everyone can control. And so what we know is that most processed food, where you have changed the texture such that

it's softer, is eaten more quickly. And there's research showing that ultra processed food, although I'm not so keen on that term as you might have gathered, but food that's classified as ultra processed according to the Noble Classification System versus minimally processed equivalents, even if it's nutritionally matched so same nutrients, is eaten fifty percent more quickly. So you're eating food that's been processed to change the texture so

softer texture fifty percent more quickly. And this is really relevant because, like I said, it causes you to overeat. And there's some fantastic research coming out of Care and Forwards Group in the Netherlands that shows that if you eat more quickly, you consume more calories. And if you are just to slow down the rate at which you eat your food by twenty scent, for example, you would actually, subconsciously without realizing it, reduce the amount of calories you're

consuming by about fifteen percent. And the reason I love this is because firstly it's related to food processing, but also we can all do something about this. We all know, I think who are fast eaters? I don't know about you, ladies, but when I sit at my dining table, my husband wolves stands food, my daughter wills down this food. My son and I eat obviously perfectly, you know, but we eat slowly. And you know, I mean most of us

know if we're fast eater liked be curious. No, you do you think you're fast or self?

rather than the processing per se. There's this really fascinating study that kimin forded where he fed people in a randomized order. On one occasion either a burger that was quite soft texture, so kind of a soft bun, soggy lettuce,

and quite soft meat patty. Then on the other occasion, the same individuals came in and they had exactly the same burger, but the gun was slightly crispy, the lettuce was slightly crispy, and the patty was slightly crispy, And he gave a huge portion to people and said, right, eat as much as you want to eat. They eate the soggy or the soft bun, the soft burger lots more quickly, and they eate more of it compared to

eating exactly the same but just crisping it up. And he's coined this lovely expression, put your crunch back into your lunch. And I think that's lovely because it empowers us firstly to consciously slow down how fast we eat. So fantastical you're going to go and copy your son when he's next home. But also I think we can do this subconsciously without thinking about it, just by changing the texture of that food as well.

where also the nutrients are well preserved. So if you take frozen peas, then because of the way that they are processed at that time and snap frozen typically at the point of harvest and put in our freezers. All the vitamin C is preserved and you've got a really cheap food and a very healthy food. And so I think that we need to be really careful and I'll use an English expression here not to throw the baby out with the bath water. That yes, there are clearly

processed foods that are bad. There are clearly processing that's bad. But it's a double edged sword. And we've done some research at King's College, London where I've done randomized control trials where I feed people whole almands versus ground almonds. So again these would be foods that have identical pack ofpack labeling, you just change through processing the structure. And what we find is if you feed people whole almonds,

you actually excreet about thirty percent of the calories. So what it means is if you are someone that's wanting to have a low energy food compared compared to what's on the back of pack labeling, consuming those almonds, it's a whole almond, actually thirty percent of the calories are just coming out the other end if you grind it. And we've done this study at our university where literally you grind it down, so you break all the cells, you absorb all of the calories. Now, why is this

the double edged sword? So for some people who are trying to lose weight, you obviously want to consume the whole almonds because lots of the calories are coming out at the other end. But there are people in our population that don't need to lose weight, that might need to put weight on, in which case, processing it to break up the food structure means they access access all

the calories. It means they access more of the other nutrients, the vitamin E for example, you'll absorb loads more, for example, from the ground almonds than from the whole almonds. And then we can also use processing to improve the health illness of the food through stealth. And this is another great way that we can actually use and harness the power processing to improve the healthfulness of the food.

just affordable, but accessible to us. We need to be practical from a point of view of how we live our lives. You know, most families now in many countries have two working parents. I don't have the time to cook everything from scratch when I get home from work. Neither does my husband. So we need to be pragmatic in this discussion about process foods as well about what's

actually practical for us. And this is where I think what we need to do is firstly accept that we can't all be perfect in our diet, and actually life would be pretty damn boring if we're all perfect, including our diet. That if we enjoy our food, great, you know, I often say that to people if your food is too healthy to be enjoyed. It's just not healthy at all. So if you get some pleasure in that heavily processed

crisps or chocolate or yogurt, fine, enjoy it. So long as the bulk of your diet comes from healthy foods to minimally processed whole foods, as long as you're getting plenty of fiber ideally from whole foods, then don't worry about having a little bit of this. You know, sometimes a bit of what's bad for you can be good

for you. And I think that again, our research that we've shown at Zori and I know I've already mentioned, has shown that really it's only about twenty percent of those processed foods that are out there that are actually really unhealthy for us. Those foods that we're just eating so so quickly, those foods that are so so tasty we don't know when we're filled, and those foods that have additives and emulsifies that are particularly harmful for us. Let's relax a little bit about the rest of them.

I personally don't want to find my egg in extra virgin olive oil because it's too fragrant in terms or too powerful the taste. Seed oils, I think is one of the most misunderstood food or ingredient at the moment. There is so much misinformation. I mean, it's mind blowing again. If you put it into Google, most of the things you get up or YouTube or Instagram are these headlines saying seed dolls are toxic, seed doors are going to

kill you. There is not evidence to support that, and there are many, many influencers out there that are making these claims that, oh, as seed oil intake went up, so did rates of heart disease obesity. Well, yeah, what else has changed over the last fifty years. It's not just seed oil intake. Also, about sixty percent of the seed all that we consume is in heavily processed, unhealthy food. What else is in that food? It's not just the seed oils. They also talk a lot about seed doors

are inflammatory. Maybe it's super physiological amounts in a test tuble in a mouse, absolutely not in humans. We know now that what is talked about from a theoretical biological pathway perspective, where we know that the main fatty acid and seed doors, which is only A six, can be converted into precursors of inflammation in a very kind of simple terms. We know that actually, our body is so clever that this doesn't actually translate to an increase in

circulating inflammatory measures. And there's meta analysis or analysis that look at loads of RCTs, loads of randomized control trials that show from about forty different clinical trials the actually eating seed oils, and I'm talking about seed doors that have been refined so they have been processed. Does not increase inflammation. In many instances, it actually has the opposite effect,

it actually reduces inflammation. And then you've got all of these big studies coming out from the big cohorts, so you know where you've got hundreds of thousands of people that have been followed over many years, and it shows though the people that consume more seed oils compared to butter or alternative animal fats have low risk of cancer, lower risk of cardiovascular disease, lower risk of all course mortality. So the evidence just does not stack up to the

claims that you see on social media. And you will never see a evidence based nutritional scientist saying seed doors are toxic. You will see many of these keto brows that are in the supermarket topless holding their bit of steak saying seed alls toxic and it's going to kill

us absolutely. And you know, I went on quite a high profile podcast earlier this year and talked about the evidence around seed oils, and after that podcast, I got four thousand Instagram messages saying that firstly, I couldn't be trusted because I was paid by the seed all industry, and I've actually never had any research found in seed

all the industry. I didn't know what I was talking about, even though I've run twenty five randomized control trials in the air of dietary fat and seed dolls on health and that I'm just down right stupid. So I had all of this. Hey, even had someone email me to say, how does it feel to be the most hated scientist in America? Because I dare to question the narrative around

seed doors because god forbid, they're also processor. Obviously they're bad for us, and absolutely no, the evidence that doesn't stack up. I think where we need to understand more is how refine seed oils compared to cold press seed doors that haven't gone through all of the same processes. So by cold press seed doors, we mean let's take some some flass seed, literally squeeze it and take the

oil out. Yes, we know that you have greater preservation of some of the bioactives like the polypemales, so yes, they might be slightly better for us. But also by not kind of cleaning up the oil, using refinement and using processes does make that cold press oil less stable. So I think it's a bit of a kind of balancing act here. But yeah, I'm very proceed oils. Oh, I'm so answer. I'm sorry so much.

What I would say is there's many that are actually fine for us, that have what I think are quite scary names, like a scorbic acid that's actually just bitumin c and it's in there to actually keep it more stable. You know, you've got to massifies like lesser thin that we think actually might be even favorable for us. But kind of the real baddies, you know, I would be quite cautious about sweetness. Not all sweetness, again, are created equally.

I would be a little bit cautious about sweetness like acek potentially sparteme sucralose, for example, But I would have that with We still don't know enough at the normal levels that these are consumed to know quite how bad they are. But I would say it's very graded that there are some that the evidence is starting to emerge that they can have quite an unfavorable effect on our got microphone, which therefore might lead to unfavorable health effects.

Where there's others that we think probably are quite inert and neutral, and there's enough for us to start grading them. But I think to off the top of my head. I couldn't kind of specify these are the real baddies.