The question: I don't like cooked vegetables. Am I missing out if I eat them all raw?
The answer: Eating plenty of vegetables every day is a good thing, raw or cooked. I advise my clients to include at least five vegetable servings in their diet each day. (One serving is equivalent to ½ cup of cooked or raw vegetables or 1 cup of salad greens.) There's clear evidence that a high intake of vegetables guards against heart attack, stroke, high blood pressure and certain cancers thanks to their generous supply of vitamins, minerals, fibre, antioxidants and protective phytochemicals.
Both raw and cooked vegetables are excellent nutrient sources. But cooked vegetables do have an edge when it comes to delivering antioxidants and minerals. Research has shown that microwaving (only until tender), baking, grilling, boiling and pressure-cooking actually increase the antioxidant content (e.g. beta-carotene, lutein, lycopene) of vegetables. Heating vegetables releases more antioxidants by breaking down cells walls. That means more antioxidants are available for your body to absorb.
Cooking vegetables also increases the amount of calcium, magnesium and iron that's available to you. Leafy green vegetables, for example, are high in calcium but much of it is bound to a natural compound called oxalic acid. Heat breaks this bond and releases some. Consider that three cups of raw spinach has 90 milligrams of calcium whereas one cup of cooked has nearly triple (245 milligrams).
To retain more water soluble nutrients such as vitamin C, thiamin and folate, steaming, quick sauteing, grilling and roasting are your best bets because the vegetables don't come into contact with water (such as boiling).
Some vegetables may be better for you if eaten raw. Cruciferous vegetables including cabbage, broccoli, cauliflower and bok choy contain phytochemicals called glucosinolates, which are converted to anti-cancer compounds when they're chopped or chewed.
The problem: heating destroys some of this enzyme, which reduces the conversion of glucosinolates to anti-fighting compounds. When it comes to cruciferous vegetables, enjoy them raw or lightly cooked until tender but crisp.
I recommend trying to sneak some cooked vegetables into your diet, especially leafy greens such as spinach, kale, Swiss chard and rapini for their outstanding beta-carotene and lutein content. If you add them to other foods, you might be surprised to learn you actually like them. Here are a few suggestions:
- Add baby spinach leaves to a tomato-based pasta sauce near the end of cooking. (The cooked tomatoes in the sauce are an excellent source of lycopene; raw tomatoes aren’t.)
- Add chopped raw kale to any soup or stew your cooking.
- Add sautéed Swiss chard to an omelette or frittata. It’s also delicious in lasagna.
- Make a green smoothie with cooked spinach or kale. Steam greens in advance and freeze them in individual servings so they’re ready to add to a smoothie.
- Make a batch of homemade vegetable soup each week to have with lunches or dinners, or as a snack.
If you decide you really don't like cooked vegetables no matter how you serve them, be sure to include a variety of raw vegetables in your daily diet. Don't get stuck on salads at every meal.
Leslie Beck, a Registered Dietitian, is based at the Medisys clinic in Toronto. She can be seen every Thursday at noon on CTV News Channel's Direct lesliebeck.com.
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