Looking for a natural immunity boost? Try fueling your diet with flavonoids, a group of plant pigments (or phytochemicals) that experts say act as—and are generally more potent than—traditional antioxidants.
"Flavonoids prevent free radical damage with their antioxidant activity and scavenge for free radicals throughout the body. [They also] block the formation of cancer-causing chemicals," explains Abbie Gellman, MS, RD, CDN, a member of the Jenny Craig Science Advisory Board. "They also prevent the synthesis and release of compounds that may promote inflammation."
Additionally, Gellman notes some flavonoids can benefit collagen, your most abundant protein. "Flavonoids have the unique ability to cross-link collagen fibers, which reinforces the matrix of connective tissues throughout our body. This includes holding tissues together, as well as being found in tendons, ligaments, and cartilage. When our bodies experience inflammation, it destroys collagen, so flavonoids can help to strengthen and maintain it," she explains, adding that some flavonoids can also modify and reduce allergic responses.
As for getting your flavonoid fix, Gellman recommends aiming for five servings of vegetables and two servings of fruits, featuring a rainbow of colors, daily: "Making sure that every meal contains vegetables and every snack contains fruit is a great starting point," she suggests.
From purple grapes to power greens, read on as nutritionists break down some of their favorite sources of flavonoids and provide quick tips for incorporating them into your meal planning today.
"Onions contain quercetin, an antioxidant that helps reduce inflammation and treat allergies, as well as promote certain hormone activities (such as insulin)," Gellman says. "Onions can be the base of anything you cook! Saute some onions as a base for soup, stew, or braised meat, or combine them with other vegetables in a stir-fry for a quick, nutrient-packed meal."
According to Gellman, grapes boast anthocyanidins (blue-purple pigments that increase vitamin C levels within cells), protect against free radical damage, and help prevent the destruction of collagen. "They make a great snack on their own or paired with other fruits. You can also add them to yogurt or oatmeal, baked goods, or salads for a sweet anti-aging boost."
"Berries are a good source of both flavonoids and vitamin C, along with fiber and biotin for healthy skin," says Olivia Audrey, ND, BCND, a board-certified doctor of natural medicine. "Blend berries (especially raspberries and blueberries) into your morning smoothie for a healthy start, and/or pace them throughout the day to stay satiated between meals. They also make a refreshing dessert!"
Risa Groux, CN, founder of Risa Groux Nutrition and the FoodFrame program, recommends incorporating leafy greens, like spinach, kale, and watercress, as well as green onions, broccoli, and artichokes, into salads and sautees for a satisfying power bowl. And don't sleep on celery, as Audrey points out that the low-calorie veggie contributes to lowering blood pressure and regulating blood sugar. "Because celery is high in fiber and water-dense, it helps to nourish cells while flushing toxins. Aim for 16 ounces of raw, juiced celery first thing in the morning on an empty stomach to help detox your GI tract," she suggests.
"Red vegetables, like hot peppers, rutabaga, red onions, and red cabbage, pack in the flavonoids and the flavor," says Groux. "Dice them up for a salad or blend them with other veggies and fruits to create fresh salsas for topping and dipping. They can also be cooked lightly and used as sides for any dish."
Herbs and Spices
Take your fruits and veggies to the next (nutritious) level with a range of herbs and spices. "Parsley, thyme, and oregano are some of my go-tos for punching up tomatoes, potatoes, and beyond. Cinnamon is also a great alternative to sugar for incorporating some additional flavor and color into your desserts," says Groux.
Citrus fruits are another flavonoid-rich and vitamin C–enhanced option for brightening up drinks, sauces, sides, fish, and more. "Some of my top picks include oranges, grapefruits, tangerines, lemons, and limes," says Groux. "They're perfect in salads, shakes, and popsicles." For a refreshing treat, check out some of our favorite DIY popsicles.
"Flavonoid- and fiber-rich legumes, like soy beans, black beans, and kidney beans, are not only nutritious, but satisfying. Add them to salads, chilis, or soups for a hearty meal that tastes good and keeps you feeling full," says Groux. Explore 26 canned bean recipes for a quick meal with staying power.
Tea and Wine
In addition to boasting high levels of flavonoids, experts suggest chamomile tea for its soothing powers. "It contains an antioxidant (apigenin) that binds to receptors in your brain that promote sleep and decrease anxiety," says Audrey. "I recommend sipping a cup of chamomile tea. And Groux adds, "In terms of flavonoid-packed drinks, you can also try green, oolong, or black tea, as well as white tea or (especially) red wine." If you do sip on red wine for its purported antioxidants, remember to enjoy it in moderation—as there is, of course, such a thing as diminishing returns with excessive wine consumption.
Last, but not least, add a decadent touch to any meal or drink with a piece of flavonoid-rich chocolate or a dash of powdered cocoa. "Opt for formulas that have minimal natural sweetener or no sugar," suggests Groux. In other words, the darker and more bitter the chocolate (i.e., the less added sugar) the better.