Very often, generic or cheaper cheese tends to have more additives and fillers that aren’t necessary, says McDaniel. Plus, they tend to score lower than brand-name fromage on taste tests and overall, don’t save you that much anyway.
This Mediterranean diet staple is one of the most frequently tampered-with foods, often cut with other oils including hazelnut, which can trigger reactions in people with nut allergies. Buying brand name is no guarantee of purity—one study found that 70 percent of olive oils tested, both brand name and generic, were revealed to not be “extra virgin” as their labels claimed. Although those findings have since been disputed, it does tend to hedge your bets since brands have reputations to uphold, and if one has been adulterated, you’re more likely to have heard about it (Bertolli, for instance, just settled a class action lawsuit about its oil).
Other things that help, says McDaniel: Look for the IOC International Olive Oil Council seal on your olive oil; buy oils in dark bottles, which protects it from oxidation; and look for a harvest date on the label (most mass-produced oils won’t have one). Don’t miss these 29 things your grocer won’t tell you.
Something like mixed nuts doesn’t have a lot of ingredients—maybe nuts, sea salt, and one or two more things. So you probably won’t find a ton of variation between brands, says Keri Gans, RD, author of The Small Change Diet. Breakfast cereals, on the other hand, can have ingredients lists several inches long. “I’d be looking closely at how much added sugar is in it? How much fiber?” she says.