The problem with diets—whether vegan, Paleo, low-carb, or low-calorie—is that most are based on what you don’t eat, says Ashley Koff, RD, a nutrition expert and author of Mom Energy (Hay House, 2011). “The best way to achieve health is to know enough [about foods] that you feel empowered to make active, participatory choices.” She dubs this nutrition approach “qualitarian.”

What’s the big challenge for consumers trying to evaluate foods? Sifting through marketing hype, says Koff. “Everybody has a publicist explaining why their product is not just good but the best, better than,” she says. Whether it’s blueberries, goji berries, or acai; Inca peanuts or regular peanuts, she says, the point isn’t which is better—they’re all good. “If a food label has to tell you why it’s good for you, that’s the first red flag.”

Social media is adding to the “static” around food trends, she says, thanks largely to the growing crowd of quasi-spokespeople who receive free product, then tweet correspondingly positive reviews. “Look up who the individual is,” she advises.

So what are true quality foods, according to Koff?

“Foods in the form closest to nature,” she says. That means organic, non-GMO, and most of the time, ones that you are personally assembling as opposed to ready-to-eat foods (unless it’s something like an apple). Local is also a plus, though she says we all deserve to eat foods we can’t get locally, imported foods that may be better quality, or fish from places where the ocean is healthier, for example.

The most under-hyped quality foods, says Koff: frozen organic vegetables and fruits; frozen quality meats and fish; beans and grains.

And the most overhyped “healthy” foods: bars, cereals and beverages. Bars are often candy bars in a different form, Koff warns. Better quality nutrition (and value) can be found in a baggie of nuts and dried fruit.