7 Surprising Antioxidant-Rich Foods, According to Dietitians

Antioxidants have made the rounds in the news for helping with hot-button topics like lowering information and risk of cancer. While there are so many different foods that have antioxidants, they are not all things you may initially think of like colorful fruits and vegetables. Let’s dive into some surprising foods that pack a punch of antioxidants, plus tips for how to include them in your day.

What Are Antioxidants? 

Antioxidants are small-but-mighty compounds in specific foods that provide nutrition benefits beyond your basic nutrient needs. Antioxidants are an umbrella term including many different types within that classification—anthocyanins, carotenoids, flavonoids, catechins, polyphenols, plus certain vitamins and minerals all act as antioxidants. 

These molecules act as the “clean up crew” in the body. They help repair and fight damaged or harmful cells, also called free radicals, that can lead to cancer, inflammation and chronic conditions like heart disease. Eating a variety of foods that are rich sources of antioxidants can help neutralize these free radicals, which in turn can help keep the body healthy. 

While several foods known to be high in antioxidants (like blueberries and leafy greens) often get all the attention, there are many lesser-known sources of antioxidants that get overlooked. “It is important to note that there is not just a handful of ‘superfoods’. Eating a mix of foods is key since they all contain unique substances that have different types of antioxidant functions,” adds one culinary nutritionist, Kristy Del Coro, M.S., RDN, LDN, based in Southern Maine. 

7 Surprising Antioxidant-Rich Foods

1. Prunes

Prunes, or dried plums, are rich in antioxidants like anthocyanins, which give them their deep purple hue and help fight cancer by reducing oxidative stress. While more research is needed, a 2023 review suggests that eating three to five servings of dried fruit per week might help lower the risk of certain cancers, including pancreatic, prostate, stomach, bladder and colon cancers, Taylor Janulewicz, RDN, an oncology dietitian, adds. Plus, prunes have higher antioxidant levels than many fruits, including blueberries, because their nutrients are concentrated from drying. This makes them excellent for supporting gut, heart and bone health, as well as healthy aging, Del Coro tells us.

2. Apples

A surprisingly nutrient-rich fruit, apples are packed with antioxidants like phloretin, which show promise in helping fight various cancers by potentially reducing cancerous cells, Janulewicz comments. They are particularly high in one category of antioxidants called flavonoids—including quercetin, catechin and chlorogenic acid, especially in the skin of the apples. 

Del Coro shares that certain apple varieties like Fuji, Red Delicious and Gala seem to have higher antioxidant levels. “It’s best to consume whole apples rather than apple juice to maximize these benefits. The flavonoids in apples may support heart health, brain health and overall immune function,” she adds.

3. Onions

Onions are another unsuspecting source of antioxidants, boasting over 25 different flavonoids, including quercetin. “Red onions also contain anthocyanins, which give them their vibrant color,” Del Coro explains. Even more surprising, a 2020 study found that onion peels have a higher concentration of flavonoids than the rest of the onion, suggesting potential health benefits from using them in soups or stocks, shares Janulewicz. Additionally, a 2019 study indicated that consuming allium vegetables like onions or garlic may reduce the risk of colorectal cancer, she adds.

4. Beans

Beans are a potent source of antioxidants, including flavonoids, phenolic compounds and vitamins like vitamin C, Alyssa Simpson, RDN, CGN, CLT says. These nutritious compounds work together to help fight inflammation, reduce the risk of cancer, alleviate oxidative stress and may also promote heart health. If you’re looking for ways to incorporate more beans into your meals, here are Our 15 Best Black Bean Recipes for Lunch and 17 Healthy Recipes That Start with a Can of Chickpeas.  

5. Potatoes

When thinking of antioxidants, most people think of colorful fruits and veggies. But you may be surprised to learn that potatoes are a significant source of antioxidants as well. “Potatoes are packed with antioxidants, most concentrated in their skins, including vitamin C for immune support, carotenoids like lutein and zeaxanthin for eye health, and phenolic acids such as chlorogenic acid, which may reduce the risk of chronic diseases,” Simpson shares. Potatoes get a bad rap, but they are rich in nutrients, low in calories and a filling energy source. Check out 22 Easy Three-Step Potato Side Dishes.

6. Nuts

Nuts are uniquely rich in antioxidants and healthy fats, offering significant protection against heart diseases and oxidative stress. Vitamin E, also recognized for its antioxidant properties, that is found in almonds and hazelnuts helps prevent heart-, brain- and age-related diseases, while selenium in Brazil nuts also contributes to these benefits, Simpson shares with us. Plus, with their high antioxidant capacity, pistachios rival other antioxidant-rich foods like blueberries and pomegranates, as demonstrated by a Cornell University study, Lauren Manaker, M.S., RDN, LD, CLEC, Charleston-based registered dietitian. 

7. Seaweed

Sea vegetables are among the most nutrient dense foods in the world, says Del Coro. There are different categories of sea vegetables (red, brown and green) and different types within each category such as dulse (red seaweed), sugar kelp (brown seaweed) and sea lettuce (green seaweed), she adds. Brown sea vegetables contain the highest antioxidant content from carotenoids such as beta-carotene, lycopene and fucoxanthin. Fucoxanthin is a potent antioxidant that is specific to algae with anti-inflammatory, anti-cancer and potentially liver protective effects, Del Coro explains.

The Bottom Line

Eating more antioxidants doesn’t mean you have to eat one specific way, and you may find a variety of nutrition benefits in unsuspecting places. Don’t be afraid to expand your palate and eat a variety of foods to increase your antioxidant intake. Not all choices must be colorful, and many foods like nuts, potatoes, onions and beans are super nutritious and offer a high antioxidant content.