We all know how important it is to eat fruits and vegetables as part of a healthy diet. Studies show that some items in particular — the “powerhouse fruits and vegetables” (PFV’s) — lower the risk of developing cancer and chronic diseases. Which ones are most protective?
In a study published in the CDC’s Preventing Chronic Disease, Dr. Jennifer Di Noia sought to rank the nutritional densities of various PFV’s based on the amounts of 17 nutrients recognized by the United Nations and the Institute of Medicine for their public health importance (potassium, fiber, protein, iron, calcium, zinc, the water-soluble vitamins B1 (thiamin), B2 (riboflavin), B3 (niacin), B6 (pyridoxine), B9 (folic acid), B12 (cyanocobalamin), and the fat-soluble vitamins A, C, D, E, and K):
Items in cruciferous (watercress, Chinese cabbage, collard green, kale, arugula) and green leafy (chard, beet green, spinach, chicory, leaf lettuce) groups were concentrated in the top half of the distribution of scores whereas items belonging to yellow/orange (carrot, tomato, winter squash, sweet potato), allium (scallion, leek), citrus (lemon, orange, lime, grapefruit), and berry (strawberry, blackberry) groups were concentrated in the bottom half.
Lenny Bernstein explains why fruit lovers might be surprised and a bit disappointed in those results:
Fruits, however, didn’t turn out to be terribly powerful in Di Noia’s rankings. Highest on the list was the red pepper (41.26), followed by pumpkin (32.23), tomato (20.37) and lemon (18.72). In fact, of the six foods that the researchers considered and decided to leave off the list, four were fruits: raspberries, tangerines, cranberries and blueberries. (The other two were garlic and onions.)
The reason for the relatively poor performance of berries, for example, is that while they are rich in phytochemicals–non-essential nutrients that have protective or disease preventive properties–”there are no uniform data on food phytochemicals and…recommended intake amounts for these compounds are lacking,” Di Noia explained. “So the scores are based on nutrients only.”
Guess we’ll just have to eat more of them!
See all the PFV rankings here.