Nutritional power couples

Peanut butter and jelly. Macaroni and cheese. Chicken and waffles. We're all familiar with food pairings that simply taste great together. But many of us aren't aware that certain combinations are actually better for our bodies than eating either item by itself.

That's because some foods work synergistically, meaning their joint effect is greater than the sum of their parts. Eaten together, these foods empower your body to absorb nutrients more efficiently. Other smart couplings promote satiety, the feeling of fullness that may be elusive when consuming just one choice or the other, says dietitian Nancy Oliveira, manager of the Nutrition and Wellness Service at Harvard-affiliated Brigham and Women's Hospital.

"Thinking about grabbing a handful of, say, grapes or nuts is okay, but there might be a benefit to a little more planning — creating snack pairings or having a meal with a few components, versus eating each one alone," Oliveira says. "You'll get a variety of nutrients, but you may also improve the absorption of vitamins, and you might feel much more satisfied for longer."

Fruitful fusions

Which foods are a nutritional love match? Consider these dynamic duos:

Beans and brown rice. Perhaps this tasty union conjures memories of leaner years when you needed to fill your belly on a budget. But the fiber-filled combination also creates a complete protein source, containing all nine amino acids we need to maintain muscle and move nutrients through our bodies. The protein and fiber in beans also slow the digestion of the carbohydrates in rice, keeping us fuller longer. We can derive similar effects by pairing whole-wheat bread and peanut butter, Oliveira notes.

Spinach and citrus. Envision a refreshing salad of spinach and mandarin oranges. This blend provides the vitamin C needed to properly absorb iron, which is plentiful in spinach, but mixing any combination of citrus fruit with spinach will achieve the same effect. Another enticing iron-vitamin C pairing can be found in hummus and bell peppers. "That makes a great snack," Oliveira says.

Cereal and milk. This comforting breakfast staple wraps in vitamin D — which is added to most cereals — with calcium in milk (which, like many dairy products, is also likely fortified with vitamin D). "Vitamin D helps the intestines to absorb more calcium so it can enter the bloodstream," Oliveira explains. Together, the nutrients keep bones and muscles healthy and help nerves function properly.

Tomatoes and olive oil. Healthy fats such as olive oil or avocadoes may improve the body's uptake of lycopene, a powerful antioxidant that can prevent cell damage implicated in cancer. In addition to tomatoes, lycopene is found in other red-hued fruits and vegetables, including watermelon, red bell peppers, and red cabbage. "There's evidence that lycopene works better in the presence of fat," Oliveira says.

Apples and peanut butter. Spreading this fan favorite on juicy apple slices is no guilty treat. The pair powers you up with a trifecta of nutrients: fiber, protein, and healthy fats. And any type of nut butter will do. "When you have those ingredients together in a meal or snack, you're more likely to feel satisfied longer than if you have the fruit alone," Oliveira says. "Protein, fiber, and fat stick around longer in the gut."

Turmeric and black pepper. This duo makes a case for spicing things up. Turmeric contains the potent anti-oxidant curcumin, but it's very poorly absorbed in the gut. Blending it with piperine — a compound in black pepper — dramatically enhances its absorption, boosting turmeric's anti-inflammatory effects.

Salmon, broccoli, and wild rice. Okay, this is a trio, not a duo. But Oliveira considers the combination particularly compelling, since the salmon and broccoli's calcium and wild rice's vitamin K are especially beneficial for bone health. "Getting these bone-promoting vitamins in one meal could be great for women who have osteoporosis," she says.

Nutritional caveats

While pairing certain foods is an easy way to get more nutritional bang for your buck, Oliveira points out some noteworthy caveats.

First, the way people absorb nourishment is highly individual. That means there's no guarantee your body will extract as many nutrients from a certain food pairing as, say, your sister does (or vice versa).

Additionally, Oliveira cautions against framing certain food combinations as "super pairings" that must be eaten together or not at all.

"Then you might limit your diet — like, if you don't have hummus on hand, you won't eat the bell peppers," she says. "You shouldn't think this is the only way to eat these foods. But if you happen to, you could benefit more."

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