We’re constantly bombarded by headlines hawking this fruit or that vegetable as being a “powerhouse,” but what does that moniker really mean? Are all plant foods created equal? What’s really healthier, an apple or a banana?
Answering these question is a tricky endeavor—much depends on a given individual’s dietary and health needs. For a person plagued with low potassium, adding a banana a day might do the trick, but for those in need of iron and vitamin C, kale may actually be a better option.
In an effort to cut down on the confusion, Jennifer Di Noia, associate professor of sociology at William Patterson University took data compiled by the U.S. Department of Agriculture and used it to determine the overall nutritional content of 47 different fruits and vegetables.
Given that cooking can adulterate the nutrient content of certain foods, Di Noia analyzed each fruit or vegetable in its raw form, measuring the levels of 17 key nutrients identified by the Food and Agriculture Organization of the United Nations and Institute of Medicine as being highly-important for health maintenance: protein, calcium, fiber, thiamin, potassium, niacin, zinc, riboflavin, folate, iron and vitamins A, B6, B12, C, D, E, and K.
Her analysis yielded 41 “powerhouse” foods—defined as offering at least 10 percent of the daily recommended value of each nutrient in a 100 calorie serving (based on 2,000 calorie diet). Here’s the list of top fruits and vegetables, in order:
2. Chinese cabbage
4. Beet green
7. Leaf lettuce
9. Romaine lettuce
10. Collard green
11. Turnip green
12. Mustard green
16. Dandelion green
17. Red pepper
21. Brussels sprout
29. Iceberg lettuce
32. Winter squash (all varieties)
35. Grapefruit (pink and red)
40. Sweet potato
41. Grapefruit (white)
The six foods that didn’t make the cut for the “powerhouse” list: garlic, tangerine, onion, blueberry, cranberry and raspberry. That’s not to say that these items are unhealthy, or that they don’t provide potential health benefits, they simply weren’t as nutritionally dense as the other 41 foods.
Di Noia emphasizes that her analysis is not the final word on what fruits and vegetables are the healthiest—there are other foods out there that could be considered “powerhouses” of other nutrients—but she says, “expressing the nutrient desirability of foods in terms of the energy they provide may help focus consumers on their daily energy needs and getting the most nutrient-dense items within the powerhouse group.”