Most of us have all too many un-fond memories of vegetables cooked into a soggy gloppy mush. With their taste and texture and vibrancy cooked out of them, it’s no wonder that so many of their nutrients are obliterated as well. With that in mind, raw vegetables rose to rule the roost in terms of nutritional virtuosity.
But for some of us, raw-everything all the time isn’t that comforting; so it’s good to know that not every vegetable is necessarily healthier when uncooked. The following exceptions to the rule actually gain in benefits when put to the heat.
1. Pumpkin and other winter squash
OK, so most people aren’t likely making raw pumpkin a staple on their menu. But if you’re forsaking cooked pumpkin (or other winter squash) in favor of something raw because you think it may be less nutritious, you can rethink that strategy. Cooked pumpkin has all kinds of wonderful antioxidants like beta-carotene which are easier to absorb once they’ve been heated up.
Raw asparagus is delicious shaved, but cooking helps break down the thick cell walls that make it hard for our bodies to absorb asparagus’ A, C, and E, and folate, according to Prevention magazine. In the case of asparagus, cooking also makes antioxidants, specifically ferulic acid, more available.
Few things beat thick slabs of summer tomatoes fresh from the garden, but cooking them releases the potent antioxidant lycopene. A high intake of lycopene has been linked to a lower risk of cancer and heart attacks. Cooking tomatoes breaks down the cell walls and release the lycopene for our bodies to enjoy. That said, cooking reduces the vitamin C content, but there are more sources of vitamin C commonly consumed, so the tradeoff is worth it.
Scientific American reports on research showing how cooked carrots have higher levels of beta-carotene, noting “Beta-carotene belongs to a group of antioxidant substances called carotenoids, which give fruits and vegetables their red, yellow, and orange colorings. The body converts beta-carotene into vitamin A, which plays an important role in vision, reproduction, bone growth and regulating the immune system.”
Andrew Weil, MD writes for Prevention that mushrooms are essentially indigestible if you don't cook them, adding: “Thoroughly heating them releases the nutrients they contain, including protein, B vitamins, and minerals, as well as a wide range of novel compounds not found in other foods. In Asian traditions, mushrooms are regarded as both food and medicine because they can support the body's natural defenses by enhancing the immune system.”
Raw versus cooked spinach offers a trade-off. Vegetarian Times writes that folate, vitamin C, niacin, riboflavin, and potassium are more available in raw spinach when it is eaten raw, cooking increases the vitamins A and E, protein, fiber, zinc, thiamin, calcium, and iron – as well, important carotenoids, such as beta-carotene, lutein, and zeaxanthin, also become more absorbable when spinach is cooked.
In the end, comparing nutrients in raw and cooked vegetables is complicated and there will be trade-offs. Rui Hai Liu, a food scientist from Cornell University reminds us that there are still many mysteries surrounding how the different molecules in plants interact with the human body.
Given what we know, the best approach seems to be: Eat a variety of fruits and vegetables, and eat them in a variety of ways. This ensures that you’re getting a mix of nutrients delivered by various methods of preparation.
The bottom line is to eat your fruits and vegetables no matter how they're prepared.
"We cook them so they taste better," Liu says. "If they taste better, we're more likely to eat them."