I’ve been standing in the dairy aisle at my local grocery store, poring over the nutrition labels on the backs of different soy, almond and oat milk containers, for 15 minutes when I decide: maybe not this week. I’ve spent the past four months reporting on ultra-processed foods and wanted to see whether it’d be possible to go even a week without them.

The problem is, I can’t find any dairy-free milks that fit the bill. The soy creamer that I’ve fixed my morning cups of tea with for nearly a decade is chock-full of ingredients I now recognize as markers of an ultra-processed product: maltodextrin, soy lecithin and locust bean gum. There are alternatives with fewer ingredients, but I’m not sure any of them fits the rules I’m trying to abide by. So I sheepishly pop my trusty soy creamer in my basket and kick the can down the road another week.

It’s three (OK, six) weeks later when I finally commit to the ultra-processed food-free week. For seven days, I will forgo industrially formulated products that are high in fats, starches, sugars and additives (like flavorings, colorings and preservatives) – which means no chips or chocolates, but also no packaged bread, yogurt with added fruit or granola bars.

Wandering the aisles, I select ingredients for a fish, couscous and vegetable stew; a quiche; and sandwiches (I’m fortunate to only be cooking for one). Crushed tomatoes are fine, but a prepared tomato spread is not; pie crust is OK if I make it from scratch, but not if I buy it pre-made. Then I stock up on snacks: apples and cheddar cheese, hummus and pita chips (many brands don’t pass muster), snap peas and mangoes.

I want a few treats so this week feels like fun, and not punishment, and while the fresh fruit is a huge treat in my book, I step into the ice cream aisle as well. Unsurprisingly, most of the brands I’d normally pick up are ultra-processed: filled with emulsifiers, thickening agents and flavorings. There’s a growing selection that aren’t – though they’re a not-insignificant $2 to $3 more per pint. That’s my first takeaway: purchasing whole ingredients and less-processed foods isn’t cheap – and with soaring food prices, it’s near impossible for many families.

Still, as I cart my groceries home, I’m eager to start cooking.

Reporting on ultra-processed foods has taken on a personal edge for me in the past year. According to the American Cancer Society, people born in 1990 – who will be 34 years old this year – have double the risk of colon cancer and quadruple the risk of rectal cancer compared with people born around 1950. Those young adults are more likely to be diagnosed with more advanced cases when their cancer is caught. Nobody knows for sure why those cancer rates are increasing in younger patients – a sedentary lifestyle, smoking, alcohol use and an ultra-processed diet could all be culprits – but scientists agree the trend is worrying enough to recommend screenings begin at age 45, instead of the long-held age 50.

Despite having no immediate family history of colon cancer or symptoms myself, I had my first pre-cancerous colon polyp removed at the age of 28. To be safe, I’ll return for screenings every five years – but in the meantime, I’ve been left wondering: how could I be living my life differently to prevent any more? Should I stop drinking? Go on daily walks? Give up all ultra-processed foods? I suspect I’m not the only young adult navigating these rapidly rising cancer rates, and wondering how much the rise of ultra-processed foods since the 1980s is to blame.

At home, I’ve hidden all of my ultra-processed snacks – chocolate-covered almonds, lemon thins, chips and granola – so I won’t accidentally start munching on them by mistake. But if anything, I’m more concerned that I’ll slip up outside the house: since the pandemic took my work fully remote, I’ve started working at coffee shops as an excuse to get out of the house more than ever before. To stop eating out entirely would require a radical shift in the ways I spend time with others – a challenge I’m not necessarily against, but that may require more planning than I’ve given this week.

As I report more on UPFs, I’m troubled by two things. Recently, I’ve stopped thinking of UPFs as food at all. Scientists will instead call these “food products” as a reminder that they’re made not so much of food, but of products extracted from food – fats, starches and added sugars – and additives.

Of all the definitions, I find Wikipedia’s the most concerning: “Ultra-processed food is an industrially formulated edible substance.” That definition gets at the heart of the other issue that’s been nagging at me: corporations engineer ultra-processed foods to be hyper-palatable (companies overseen by former tobacco company executives produce the most hyper-palatable foods). I’m frustrated by the health impacts of ultra-processed foods not because I think people are making bad decisions by choosing to eat them, but because I suspect corporations don’t care how their products affect consumers.

Halfway through the week, as I’m whipping up a PB&J sandwich (made with locally packaged jam, processed – but not ultra-processed – peanuts, and bread from a nearby bakery), I reflect on how grateful I am to only be feeding myself. The handful of meals that I have time to cook from scratch stretch easily through the week. That wouldn’t cut it for many of my friends and family with children to feed.

For many families in my life, it’s not just the cost of whole foods that keeps them buying UPFs, it’s the convenience. A box of mac and cheese, takeout from a fast-food restaurant, pre-packaged cookies, crackers, yoghurts and sandwiches – they’re what make it possible for dozens of working moms I know to feed picky kids. I’m reminded of an offhand comment one nutritionist made while we were talking about ultra-processed foods: not enough gets said about the domestic labor it would require, most likely from women, to transition away from them.

In his book Ultra-Processed People, the infectious disease doctor Chris van Tulleken describes how awful he felt after a month of eating only ultra-processed foods. I don’t know that I feel any noticeable difference after a week of not eating any UPFs – but maybe it takes longer to feel a positive difference than a negative one. Or maybe I’m lucky to be starting from a place of not eating many UPFs to begin with. Either way, I’m not sure that I’ll commit to a UPF-free lifestyle forever like Van Tulleken did. I’m happy to add my own fruit and honey to Greek yoghurt and cut back on chips, but I’m also deeply grateful for certain products, mostly those plant-based milks, especially when I think about the environmental toll of conventional dairy.

But I do take time to browse Northeastern University’s UPF database, TrueFood, a handy tool I found invaluable for looking up most grocery store products throughout the week. Although all plant-based milks are technically ultra-processed, there are many that rank as much less processed on the website’s scoring system.

When I head to the grocery store next week, I’ll be picking one of those up.

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