Some foods just go together. Matches made in culinary heaven like salsa and guacamole or pasta with olive oil and tomato sauce, and of course, rice and beans or a beautiful salad tossed with an herby vinaigrette. You know this already because they are delicious and make sense on the plate. But the big surprise is, they don’t just taste good together, they actually enhance each other nutritionally, too. It’s called nutritional synergy where nutrients in one food pair up to enhance the levels of another, and that’s what make whole foods even more interesting (and important) in a whole foods diet!
Black beans and rice is oh, so nice. When beans and rice are paired together at a meal (or even eaten separately but over the course of the day), they supply what’s called a complete protein. While high glycemic rice can increase blood sugar more rapidly than other foods, a study with a small group of non-Hispanic white adults with type 2 diabetes showed that meals that combine beans and rice can help reduce post-meal blood sugar responses, compared to eating rice alone.1 Most traditional dietary patterns have common food pairings that also provide a complete protein: falafel and hummus on whole wheat pita, bean and barley vegetable soup, black beans and corn salad, tofu and brown rice, pasta e fagioli (pasta and beans) and even a classic peanut butter sandwich on whole grain bread.
Walnut and tart cherry trail mix. Sounds simple and it is. Already a perfect pair in tasty portable convenience (a great travel snack or when you’re heading to the gym!), walnuts with their high levels of plant omega-3 alpha-linolenic acid (2.5 grams of ALA per one ounce serving) and tart cherries providing an excellent source of vitamin A (25% daily value), both are two food sources of melatonin,2,3 an important plant compound related to maintaining a healthy sleep cycle. And now, animal research has shown that this dynamic duo has greater anti-inflammatory effect when paired together.4 Although more research is needed to clarify the benefits in humans, you can still enjoy the creative combos of these two foods. Here’s Chef Richard Brown’s Quinoa Salad with Toasted Walnuts, Roasted Chicken and Dried Cherries for a savory meal. And here’s my Walnut Milk and Cherry Berry Smoothie you can add to your smoothie repertoire.
Roasted broccoli and tomatoes with garlic, basil and oregano. These two vegetables go well together raw in salads and as crudités, and they also are a delicious combo when pasta is topped with tomato sauce and lightly sautéed broccoli. Animal research from the University of Illinois has shown that when broccoli and tomatoes are eaten together they may have more of an impact in slowing prostate cancer tumor growth than when eaten separately. 5 However, more research is needed to understand how these benefits translate to humans.
Spinach and strawberries – and add walnuts and goat cheese to enjoy as a salad. When you pair vitamin C-rich foods like strawberries with foods that contain iron like spinach, the body can absorb more iron. 6,7 This goes for any combination of vitamin C and iron including other tasty examples like a bean burrito with salsa or a cool farro salad with mango. Although these particular food pairings have not been studied together, it is well-documented that vitamin C can enhance the absorption of iron.
Guacamole and salsa with baked tortilla chips and vegetable crudités. It’s true—guacamole and salsa really are meant to be side-by-side like a married couple: complementary and yet with their unique differences. Avocados and salsa are nutritious on their own, but when combined, the avocado’s fat and other nutrients may enhance the absorption of carotenoids from the tomato salsa including lycopene and beta-carotene by more than 400% and 260%, respectively. According to this study, which was done in a small group of healthy adults, avocado also has this charming synergistic influence on other foods, including romaine lettuce, spinach, and carrots, resulting in a boost in carotenoid plant nutrients like alpha-carotene, beta-carotene and lutein by 4 to 15 times!8
A convenient make-at-home granola featuring walnuts and raspberries. A number of studies suggest that eating walnuts has a beneficial effect on inflammation. An animal study showed that these benefits may be increased when walnuts are paired with certain other foods including raspberries, though further studies are needed to understand the impact on humans.4 Raspberries and walnuts are a delicious addition on salads and to accompany your morning oatmeal. And here’s Chef Molly Katzen’s tasty Gluten-Free Walnut-Raspberry Granola perfect for making ahead to have on hand for a quick and portable breakfast or snack.
Salad with real vinaigrette. Oils like canola oil increase the absorption of important plant nutrients called carotenoids from vegetables like leafy greens, carrots and tomatoes, according to a study done in a small group of healthy adults.9 I like to use extra virgin olive oil and white balsamic vinegar in 2:1 ratio and add Italian seasoning, a pinch of sea salt and a couple cranks of whole black pepper for an easy go-to dressing. Here’s a Garden Salad with Walnut Vinaigrette recipe that’s simple and delicious.
Enjoy tea time with green tea with lemon or a squeeze of orange juice. What’s so special about this familiar pairing? Well, a cell study shows that citrus juices, may enhance absorption of certain catechins, which are abundant in tea.10 Catechins are a class of phytonutrients, or “plant nutrients,” that may provide a variety of health benefits.11 Although more research is needed to understand how these absorption effects benefit humans, you can certainly enjoy the delicious combination of tea and citrus.
Boost the herbs and spices in meals when you eat rich foods. Sure, herbs and spices can make any meal taste delicious, but a study from Penn State showed that when a small group of healthy, overweight adult men included a generous amount of a spice and herb blend with a fatty meal, post-meal triglycerides were reduced by 31% compared to the same meal without the herbs and spices, which are high in naturally-occurring plant compounds.12 While it’s expected that triglycerides increase temporarily after a high fat meal, if it happens too often it is thought to increase risk of heart disease. Get creative making herb and spice blends for rubs and marinades that include some of these: oregano, cinnamon, cloves, garlic powder, ginger, paprika, rosemary, turmeric, and black pepper.
Some of these studies were performed on cells or animals, so further research is needed to confirm the benefit humans receive from pairing certain foods.4,5,10 Larger and longer-term studies, as well as studies in more diverse populations, are needed to clarify the potential health benefits afforded by these food combinations.1,6,7,8,9,10,11,12
References
1Thompson SV, Winham DM, Hutchins AM. Bean and rice meals reduce postprandial glycemic response in adults with type 2 diabetes: a cross-over study. Nutr J. 2012;11:23.
2Reiter RJ, Manchester LC, Tan DX. Melatonin in walnuts: influence on levels of melatonin and total antioxidant capacity of blood. Nutrition. 2005;21(9):920-924.
3Burkhardt S, Tan DX, Manchester LC, et al. Detection and quantification of the antioxidant melatonin in Montmorency and Balaton tart cherries (Prunus cerasus). J Agric Food Chem. 2001 Oct;49(10):4898-902.
4Luo T, Miranda-Garcia O, Adamson A, et al. Consumption of Walnuts in Combination with Other Whole Foods Produces Physiologic, Metabolic, and Gene Expression Changes in Obese C57BL/6J High-Fat–Fed Male Mice. [published online ahead of print August 3 2016]. J Nutr. 2016. doi: 10.3945/ jn.116.234419.
5Canene-Adams K, Lindshield BL, Wang S, et al. Combinations of tomato and broccoli enhance antitumor activity in dunning r3327-h prostate adenocarcinomas. Cancer Res. 2007;67(2):836-43.
6Hallberg L. Iron and vitamins. Bibl Nutr Dieta. 1995;(52):20-9.
7Teucher B, Olivares M, Cori H. Enhancers of iron absorption: ascorbic acid and other organic acids. Int J Vitam Nutr Res. 2004;74(6):403-19.
8Unlu NZ, Bohn T, Clinton SK, et al. Carotenoid Absorption from Salad and Salsa by Humans Is Enhanced by the Addition of Avocado or Avocado Oil. J Nutr. 2005;135(3):431-436.
9Brown MJ, Ferruzzi MG, Nguyen ML, et al. Carotenoid bioavailability is higher from salads ingested with full-fat than with fat-reduced salad dressings as measured with electrochemical detection. Am J Clin Nutr. 2004;80(2):396-403.
10Green RJ, Murphy AS, Schulz B, et al. Common tea formulations modulate in vitro digestive recovery of green tea catechins. Mol Nutr Food Res. 2007;51(9):1152-62.
11Hursel R and Westerterp-Plantenga MS. Catechin- and caffeine-rich teas for control of body weight in humans. Am J Clin Nutr. 2013;98(6 Suppl):1682S-1693S.
12Skulas-Ray AC, Kris-Etherton PM, Teeter DL, et al. A high antioxidant spice blend attenuates postprandial insulin and triglyceride responses and increases some plasma measures of antioxidant activity in healthy, overweight men. J Nutr. 2011;141(8):1451-7.