They also consumed more calcium, iron, folate, fiber, and vitamins C, E, B6, and B12.

CNN: Why family meals matter

The Maya nut has high levels of nutrients including protein, calcium, fiber, iron and vitamins A, E, C and B.

CNN: Maya nut changes lives while aiding the rain forest

These little beans are nutrition powerhouses, packing protein, fiber, iron, manganese, folate, thiamin, potassium and other nutrients into a modest calorie count, with just a speck of fat and no cholesterol.

NPR: Falling in Love with Limas

ANTIOXIDANTS, FIBER , calcium, iron, potassium: These are our mantras in the aftermath of December's excesses.

WSJ: Michael Anthony's Kale, Cabbage and Carrot Salad | Slow Food Fast

To come up with his index, Drewnowski ranked foods based on their concentrations of nine essential nutrients (protein, fiber, calcium, iron, magnesium, potassium, vitamins A, C, E).

FORBES: Cheap Foods That Are Good For You