Cooking vegetables doesn’t always reduce their vitamin and antioxidant content. Some vegetables, such as tomatoes, carrots, and spinach, are actually more nutritious when cooked.
Cooking asparagus with oil may offer more antioxidants and fat-soluble vitamins.
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Cooking asparagus softens it and breaks down its cell walls, which releases antioxidants like chlorogenic acid. Research suggests that cooked asparagus may offer higher levels of antioxidants than raw asparagus.
Many people cook asparagus with a little olive oil. The added fat helps your body absorb fat-soluble vitamins in asparagus, like vitamins E and K.
To keep the most beneficial compounds and nutrients, choose gentler cooking methods. Good options include steaming or lightly sautéing.
Cooking carrots can give you more beta-carotene, an antioxidant plant pigment.
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Carrots are high in beta-carotene, a plant pigment with antioxidant properties. Your body converts beta-carotene into vitamin A, which supports healthy vision, immune function, and skin health.
Cooking has been shown to increase the amount of beta-carotene your body can absorb compared to eating raw carrots. One study found that stir-fried carrots had about 75% beta-carotene available, while raw carrots had only about 11%. This is likely because cooking breaks down the carrot’s cell walls and because beta-carotene is fat-soluble. This means it’s absorbed better when a source of fat is present, such as olive oil.
Cooking tomatoes may help increase the lycopene, an antioxidant.
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Cooking tomatoes increases the amount of lycopene, a powerful antioxidant that may help protect your heart and support healthy aging. Cooked tomatoes also have less oxalic acid. This may be helpful for people who need to limit oxalates, such as those who are prone to kidney stones.
Note: Cooking does lower the vitamin C in tomatoes because vitamin C breaks down when it’s heated.
Cooking mushrooms for a short time can improve their antioxidant content.
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Mushrooms are another vegetable that’s healthier when cooked. As with asparagus and tomatoes, cooking increases their antioxidant content. Quick cooking methods, such as steaming or microwaving, are most beneficial. Cooking them for too long may reduce some beneficial nutrients and lessen their health benefits.
One study found that cooking mushrooms for 15 minutes caused flavonoid levels to increase by around 811%. Flavonoids are antioxidants that may help reduce inflammation and protect the body over time.
Steaming spinach can increase the beta-carotene availability.
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Both raw and cooked spinach are nutrient-rich and offer many health benefits. However, like carrots, cooking can increase the amount of beta-carotene your body absorbs. How you cook it makes a big difference. Boiling can lead to more antioxidant losses, while steaming helps your body absorb more beta-carotene.
Cooked spinach also appears to be higher in minerals like iron and calcium. Some research suggests this increase happens because minerals bind to compounds like oxalates, which keeps the minerals from being lost in cooking water. However, even gentle cooking methods like steaming can reduce vitamin C by up to 60%.
There are many simple ways to include more cooked vegetables in your meals. Using gentle cooking methods like steaming, microwaving, or lightly sautéing can help preserve nutrients. Here are a few easy ideas:
Serve steamed asparagus or carrots for an easy side dishStir spinach into eggs, pasta, or soupsAdd sautéed mushrooms to salads, grain bowls, or steakSimmer tomatoes into sauces or use them in soups and stewsBatch-prep a mix of sautéed vegetables to add to meals throughout the week