Flickr / Marawder Don't let a loyalty to national brands decimate your paycheck.

Although millions of dollars in marketing is meant to convince you otherwise, store-brand products are often just as good as name-brand products and cheaper, too.

That's why more informed shoppers are more likely to buy store-brand, according to a 2014 study from the University of Chicago's Booth School of Business , which found that chefs tended to buy store-brand foods and medical professionals tended to buy store-brand drugs.

If this surprises you, it may be because store-brand products, sometimes called generics, used to be a class below name-brand, according to Tod Marks, senior projects editor at Consumer Reports.

"'Generics' is derogatory," Marks says. "It harkens back to the 1970s when the economy was struggling and a lot of stores came out with generic products. They were canned or packaged goods in nondescript, simple containers that said 'green beans,' or 'peaches.' They weren't very good, but they were cheap, and when the economy wasn't very strong they appealed to a lot of people."

The price-over-quality model has gone out of style, however, and today we have store brands like Whole Foods' 365 brand, Costco's Kirkland Signature, or Target's Archer Farms, all of which tend to get high ratings from consumers.

Store brands, also known as private label products, "are made to high-level specifications put forth by the manufacturer," Marks say. They aren't necessarily meant to be exact copies of national brand products — often, they stand on their own (consider Trader Joe's, where the only products available are from the store).

One reason they're cheaper than their national brand counterparts is that they don't have the research, development, and advertising costs, so they're able to skim that off the price. By and large, Marks estimates, store brand grocery store products cost about 25% less than national brands.

Of course, some name-brand products are still worth it — but finding out when is tricky.

Looking back at that Booth study, it seems that store-brands make more sense for some products and less for others. Here's a chart of how likely chefs were to buy store-brands in different categories (most likely on top):

University of Chicago Booth School of Business

You'll see that professional chefs are more likely to buy the store-brand versions of a few products in particular:

• Pantry staples, like salt, sugar, and baking soda

• Dried, frozen, and canned fruit

• Baking mixes

• Frozen and canned vegetables

• Spreads, like jams, jellies, and "dairy spreads" (not including butter)

• Breads and baked goods

• Cheese