Every week, millions of people push their carts down supermarket aisles, picking up products that look harmless enough on the outside. Nice packaging, words like “natural,” “light,” or “high protein” printed in bold. It all feels so reassuring. Honestly, it can be anything but.
Chefs and nutritionists see the grocery store very differently from most of us. They know exactly which products to walk straight past. So I decided to ask around, dig into the latest research, and put together something genuinely useful. What follows might make you rethink a few items on your next shopping list.
1. Ultra-Processed Foods: The Big Umbrella You Can’t Ignore
Let’s start with the elephant in the room. Newly released federal dietary guidelines for Americans call for fewer ultra-processed foods, and the science backing that advice is overwhelming. A 2024 umbrella review of 45 meta-analyses including almost 10 million people found that diets high in ultra-processed foods are linked to 32 health conditions, including obesity, type 2 diabetes, cardiometabolic diseases, many cancers, gastrointestinal disorders, asthma, anxiety, depression, cardiovascular events, and all-cause mortality.
A 2024 review of 45 meta-analyses, covering nearly 10 million study participants, found “convincing” evidence that a diet high in ultra-processed foods increases the risk of death from cardiovascular disease by roughly half and the risk of anxiety by nearly the same margin. Think about that the next time you reach for something that lists twenty ingredients you can’t pronounce. According to nutrition experts, a quick way for consumers to avoid ultra-processed foods is to read the ingredients list on packaged foods closely.
2. Processed Deli Meats: The Worst Offender in the Chilled Aisle
Processed meats, including deli meats and chicken nuggets, are ultra-processed foods linked to cancer, cardiovascular disease, diabetes and dementia. That’s a sobering list for what so many families toss into lunchboxes without a second thought. Ultra-processed meats have been classified by the WHO as a Group 1 carcinogen, a categorization shared by tobacco and asbestos, for their link to colorectal cancer.
Deli meat, bacon, and hot dogs are all examples of processed meats that contain lots of sodium and nitrates. Excessive sodium consumption isn’t great, but nitrates have been linked to certain types of cancer, making them incredibly unhealthy. Chefs often say there’s simply no culinary reason to buy mass-produced deli meats when whole cuts of freshly cooked chicken or turkey are easy to prepare in batches and taste infinitely better.
3. Sugar-Sweetened Beverages: The Liquid Mistake
Sugar-loaded soft drinks should be skipped, experts say. Sweetened sodas are an ultra-processed food linked to obesity, diabetes and dental disease in children. This isn’t a new warning, but it’s one that keeps getting ignored at checkout. Sugar-sweetened beverage intake was associated with at least an 8% average increase in type 2 diabetes risk and a meaningful increase in heart disease risk.
In general, regular soda consumption has been linked to an increased risk of health complications like diabetes, heart disease, and liver cancer. Here’s the thing though – it’s not just soda. Fruit-flavored drinks with bright colors and friendly labels are often just as bad. Some of these drinks have at most ten percent juice according to their ingredient lists. Not only do they have high fructose corn syrup, but they also have multiple sources of artificial sweeteners in addition to artificial colors.
4. Ultra-Processed Protein Bars and Shakes: Marketing Over Nutrition
All four nutrition experts asked by Newsweek agreed that ultra-processed protein bars and shakes should be left behind. It sounds counterintuitive. Protein is good, right? The problem is the delivery vehicle. Many shoppers are starting to ask how much of what’s in these products, from the powders and bars to celebrity-branded protein waters, is marketing over real substance. Despite rules requiring “high-protein” labelled products to meet certain thresholds, many barely hit the mark.
Foods with the words “natural flavors” in their ingredient lists should also raise red flags, nutritionists say. Despite the name, natural flavors are often just as processed as artificial ones. Nutritionists point out that for most people, whole food protein sources like eggs, legumes, fish, or Greek yogurt deliver everything the body needs without the lab-designed additives.
5. Commercially Produced Pastries and Margarine: Trans Fat Traps
Dietitian Susie Burrell disclosed that she never purchases commercially produced pastry-based foods. She identified them as “one of the few supermarket foods likely to still contain trans fats especially when margarine is on the ingredient list.” Trans fats are a particularly nasty kind of fat because of what they do inside the body. Margarine is high in trans fat, which has been shown to lower “good” HDL cholesterol and raise “bad” LDL and total cholesterol.
Trans fats, also known as hydrogenated or partially hydrogenated oils, are vegetable oils that have been “reconfigured” to extend their shelf life, but ultimately harm your cholesterol levels. The irony of buying something that looks like a treat, a croissant, a danish, a pastry puff, only to discover it’s silently damaging your arteries, is a hard pill to swallow. Chefs almost universally say: bake your own or skip it entirely.
6. Bagged Pre-Washed Salad: A Convenience with Hidden Risks
Bagged lettuce is notorious for being constantly linked to E. coli and listeria, with “far too many outbreaks and recalls and a lack of transparency and traceability.” Food safety expert Darin Detwiler, chair of the National Environmental Health Association’s Food Safety Program, has been vocal about this. He notes that, according to the Department of Health and Human Services, almost a sixth of the American population will experience a foodborne illness every year.
I think a lot of people assume the “pre-washed” label means it’s actually safe. It often just means someone ran it under water quickly in a facility you’ve never seen. Detwiler has seen workers in the produce section cleaning the floor, not washing their hands, then cutting and packaging fruits. He explained that this “is where we find contamination issues, cross-contamination, and increased time when food is no longer safe and pathogens grow before we even buy them.” Buying a whole head of lettuce and washing it yourself is cheaper anyway.
7. Pre-Cut Fruit: Pay More, Risk More
Many food safety experts say fresh fruits cut at the supermarket are not a safe choice, with one expert noting that “convenience should not be a priority over protecting ourselves and our families.” Buying pre-cut fruits and vegetables can save you time, but it’s often best to avoid it. Not only can you end up paying more in the end, since there are often large markups, but there are also potential sanitation risks and environmental concerns, and a risk of contamination since employees may not have washed their hands properly or worn gloves before cutting and packaging the fruit.
Think of it like this: when you cut a watermelon at home, you know exactly what knife touched it and when. In a supermarket, that same watermelon might have passed through a dozen hands on a shared surface. Shoppers should avoid pre-cut fruit for safety reasons, according to leading food safety voices. The price markup alone, often double or triple what whole fruit costs, makes this an easy swap to make.
8. Sweetened Children’s Cereals: Candy for Breakfast
Some children’s breakfast products, including toaster pastries and most sweetened cereals, are ultra-processed and linked to obesity, diabetes and mental health problems. The packaging is the real masterclass in deception. Cartoon characters, claims of added vitamins, whole grain labels up front. Flip the box over and you find the truth. When you check the labels of some popular cereals, the sugar content can be strikingly high. As one registered dietitian-nutritionist notes, such cereals “contain high added sugars, contributing to excess calorie intake and increasing the risk of heart disease and high blood sugar levels.”
Many children eat cereal daily. Surprising reports have found disturbing levels of certain toxins in common children’s cereal. According to testing by the Center for Environmental Health and others, many children’s breakfast cereals contain glyphosate and arsenic. Glyphosate is considered a “probable human carcinogen” by the World Health Organization. Plain oats, fruit, and eggs are what nutritionists consistently recommend as the real breakfast of champions, not something brightly colored in a box.
9. “Lite” and “Reduced Fat” Products: The Sneaky Swap
Any time you buy something that’s reduced sugar and fat, manufacturers have basically replaced it with added sugar, emulsifiers, and different additives to make it still taste good and give it the same texture as the regular version. That’s the cruel trade-off nobody talks about. You think you’re being virtuous, but you’re often just swapping one problem for another. Ultra-processed foods contain added fats, sugar and sodium, in addition to additives and stabilizers.
Chefs in particular have zero patience for “lite” products. They argue that a small amount of real, full-fat yogurt or proper olive oil does far more for flavor and satiety than a larger portion of something chemically engineered to be lower in calories. Nutrition experts acknowledge that not all processed foods are bad. Things like whole-grain bread or tofu, while considered processed foods, are still “health promoting.” The lesson: judge by what’s actually in it, not what the front label promises.
10. Instant Noodles and Packaged Frozen Meals: Cheap in Price, Costly in Health
Instant noodles might be a quick, inexpensive lunch or snack hack. Still, the packets contain some of the most shocking amounts of sodium you’ll ever see on packaging. For context, many single servings of instant noodles deliver close to the full recommended daily sodium limit in one sitting. Plenty of frozen meals are ultra-processed and filled with high sodium, sugar, additives and calories. Studies published in the British Medical Journal in 2024 show that serious health risks like cancer, cardiovascular issues and more are linked to ultra-processed foods.
There’s scientific evidence that diets rich in ultra-processed foods are linked to an increased risk of cardiovascular disease, mental health disorders, diabetes, obesity, sleep problems, and even premature death, as Harvard Medical School has reported. The frozen aisle is not entirely off limits – plain frozen vegetables and simple proteins are genuinely useful staples. But the pre-made meals packed with sauces, fillers, and preservatives? Nutritionists and chefs both say leave them where they are.
