Antioxidants are compounds critical to the production of energy and to maintain health and youth. Dr. Jacob Teitelbaum, the creator of the free app Cures A-Z, tells Newsmax Health that although oxygen is necessary for survival, too much of it is toxic.

“Using oxygen to create energy in our bodies results in the production of toxic ‘free radicals’ which set up ongoing, self-sustaining chain reactions of molecular damage,” he explains. “Doctors who specialize in anti-aging medicine use antioxidants as well as other key tools like bioidentical hormones to keep their patients healthier longer by preventing free radical damage.”

The best way to obtain antioxidants is through food, says noted sports medicine physician, Dr. Gabe Mirkin. “Eating fruits, vegetables, nuts and legumes will help you get the intake of antioxidants you need.”

Here are 10 foods chock full of the good stuff:

1. Dark Chocolate. Teitelbaum says that eating dark chocolate is a “fun way to get antioxidants.” According to the results of a study conducted at Cornell University, the concentration of cancer fighting antioxidants in hot cocoa was significantly higher than red wine, green tea or black tea.

2. Pecans. Nuts are good source of healthy fats and minerals and also contain a high amount of antioxidants, says Mirkin. One study found that people who consumed 20% of their total calories from pecans experienced significantly increased blood antioxidants levels.

3. Blueberries. While eating large amounts of sugary fruit is not recommended for those with diabetes, blueberries are low in calories and sugar but packed with antioxidants. Animal studies have shown that blueberries may stave off cognitive decline. In addition, the anthocyanins in blueberries have been shown to reduce the risk of heart disease, lowering LDL levels and blood pressure.

4. Strawberries. Now in season, these are among the most popular berries on the planet. They also contain anthocyanins which help reduce the risk of heart disease. The brighter the red, the higher the amount of antioxidant anthocyanins.

5. Artichokes. This tasty veggie has a long history of healing properties and is a great source of dietary fiber, minerals and antioxidants. They are especially rich in the antioxidant known as chlorogenic acid which may reduce the risk of certain cancers, type 2 diabetes, and heart disease.

6. Kale. This hearty green vegetable is one of the most nutritious of the plant world, says Mirkin. It’s rich in vitamins A, K and C as well as antioxidants. The red leafed variety of kale contains higher levels of these antioxidants which is why nutrition experts advise us to eat a rainbow diet—foods rich in color.

7. Beans. These legumes are inexpensive and healthy while being incredibly rich in fiber, says Mirkin. They are also one of the best plant sources of antioxidants. One of these is called kaempferol, which has been linked to anticancer benefits.

8. Beets. These veggies are a great source of fiber, potassium, iron, folate and antioxidants. Several test-tube studies have shown that beets lower the risk of certain cancers in the colon and digestive tract thanks to a group of antioxidants compounds called betalains. Betalains have been also linked to reducing inflammation and relieving arthritis pain.

9. Spinach. This nutritionally dense but very low calorie vegetable is loaded with vitamins, minerals and antioxidants. It’s a great source of lutein and zeaxanthin, two antioxidants that help protect your eyes from UV damage.

10. Tomatoes. The health benefits of tomatoes include eye care, good stomach health and reduced blood pressure. This popular fruit often mistaken for a veggie also includes a number of antioxidants that have been proven to fight different forms of cancer, according to the Harvard School of Public Health. Tomatoes contain lycopene, an antioxidant that is highly effective in fighting the cancer-causing free radicals. Remarkably, the health benefits can be obtain from even processed tomato products like ketchup.