It seems intuitive that a veggie in its raw state would be more nutritious than its cooked counterpart. But the truth is some veggies are actually healthier when things heat up a bit. High temperatures do diminish some of the vitamins and minerals in veggies by 15 to 30 percent, but boiling is the biggest culprit. Sautéing, steaming, roasting and grilling minimize the losses. And cooking actually increases the levels of some nutrients by breaking down the cell walls of the plant where the nutrients are locked in. Here are three delicious examples:
In the summer I pop grape tomatoes like M&Ms, but research shows that when cooked the lycopene content of these juicy gems increases by about 35 percent. Lycopene, the antioxidant responsible for tomatoes' ruby hue, is linked to protection against several types of cancer, including prostate, pancreas, breast, cervix and lung, as well as a lower risk of heart disease, our nation’s #1 killer of men and women.
How to Cook: I love to slice grape or cherry tomatoes in half and sauté in extra virgin olive oil with garlic and onions, then toss with strands of steamed spaghetti squash. It’s amazing hot or as chilled leftovers the following day.
A fresh carrot with its fluffy green top is undeniably one of the most gorgeous veggies on earth, but cooking can boost its levels of beta-carotene by over 30 percent. This key antioxidant supports our night vision, guards against heart disease, several cancers (bladder, cervix, prostate, colon, esophagus) and is a particularly potent lung protector.
How to Cook: Brush or mist with extra virgin olive oil, roast at 425 F for 25 to 30 minutes. Drizzle with balsamic vinegar and continue roasting another 3-5 minutes. To preserve even more antioxidants chop after cooking.
Spinach salad is one of my staple spring go-to meals, and I toss fresh baby spinach leaves into fruit smoothies, but cooking spinach has been shown to boost levels of lutein, an antioxidant that prevents against cataracts and macular degeneration. Heating leafy greens can also help you absorb more calcium. That’s because in its fresh state the calcium binds to a natural substance called oxalic acid, which reduces its absorption, but cooking helps to unbind the two. Cooked spinach is also more compact, so you get more nutrients per bite — three cups raw packs 89 milligrams of calcium compared to 245 milligrams in 1 cup cooked.
How to Cook: Warm hot chili oil in a skillet over medium heat. Add crushed garlic and sliced red bell peppers and sauté until tender, about 2-3 minutes. Add a few large handfuls of fresh spinach and stir until wilted.
For overall nutrition it’s best to eat a mixture of raw and cooked veggies, but since 75 percent of Americans fall short of the recommended three daily servings, the most important message is: eat them any way you like them!
Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is Cinch! Conquer Cravings, Drop Pounds and Lose Inches.