The easy ultra-processed food swaps Dr Chris Van Tulleken swears by

Ultra-processed foods (UPFs) are incredibly hard to resist, as Doctor Chris Van Tulleken on the BBC iPlayer documentary Irresistible – Why We Can't Stop Eating shows.

People in the UK are among the biggest eaters, external of UPFs – they make up over half of calories consumed by adults, external.

There isn't a single definition of UPFs but they generally contain ingredients not used in home cooking.

"This was explained to me by a scientist who works in the food industry," says Van Tulleken, author of Ultra Processed People. "I said 'if I'm making a chocolate brownie at home, surely it's basically the same as one I buy in the shop?'

"He explained there are two important differences. Firstly, the shop-bought one will use much more fat, salt and sugar."

"The second difference is the shop-bought one will use additives, fats and sweeteners, emulsifiers, stabilisers, colourings and flavourings."

Having conducted an enormous amount of research on UPFs, Van Tulleken mostly sticks to a UPF-free diet.

"I'll still have some if I'm at a party. People expect me to refuse it but I'm not like that," he says. "But I genuinely don't want to eat much of it at all. I was forced to learn how bad it was for me and so it holds no attraction for me."

So what swaps has Van Tulleken made to ditch UPFs?

First, he recommends swapping jars of shop-bought pasta sauce for passata (sieved tomatoes).

"All these scientists in the food industry have taught me to add a bit of salt, oil and vinegar to passata. It's brilliant. If you've got an extra couple of minutes, you could also fry up some garlic and onions.

"If you really want to keep things simple, even just a can of tomatoes with a bit of salt will be fine."

"I've found the best formula for stir-fry sauce and it's incredibly quick to make. It's one-third water, two-thirds soy sauce, some sugar, sesame oil and a splash of any type of vinegar. You could add some spices like star anise," suggests the scientist.

"The one bit of advice I will give anyone is that humans should only drink water or, if your culture allows it, milk.

"If you're wanting a caffeinated drink, rather than an energy drink, coffee is just beans and water, so that's good. A cup of tea is fine, too."

You don't need to deprive yourself of a little added extra, either, he says…

"Add sugar and salt to your food if you want and don't feel bad about it. You'll definitely add less sugar and salt than the food industry does.

"A can of cola is nine teaspoons of sugar, external. In the equivalent-sized coffee, even if you have a sweet tooth, you're still only going to go for two spoons of sugar, so just enjoy your food."

"I buy chopped frozen fruit, like mango, and then stir it up with natural yoghurt and, if it needs it, I add a little sugar. It's brilliant!"

"I could eat an entire tub of salted nuts. With raw nuts, you will eat half as many."

If you're craving the salty hit of crisps, though, Van Tulleken says to "get a little dish of salt and dip the raw nuts in".

"People talk about how there are frozen chips that are just potato and a bit of oil, but the ones I find are covered in maltodextrin and flavourings," says Van Tulleken.

"I just chop up a potato and cook it in the oven with a bit of oil and salt."

Originally published November 2024. Updated February 2026

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