Raw food diets are fairly new orient oneself, including raw veganism. The belief being that the less processed food the better. However, not all foods are more nutritious when eaten raw. This is because some vegetables are actually more nutritious when cooked. Here are nine.
All living things are made up of cells, and in vegetables, important nutrients are sometimes trapped in these cell walls. When vegetables are cooked, the walls break down, releasing nutrients which can then be absorbed more easily by the body. Cooking asparagus breaks down its cell walls, making vitamins A, B9, C and E more available for absorption.
Mushrooms contain high amounts of ergothioneine, an antioxidant released during cooking. Antioxidants help break down “free radicals,” chemicals that can damage our cells, causing disease and aging.
Spinach is rich in nutrients, including iron, magnesium, calcium and zinc. However, these nutrients are more easily absorbed when spinach is cooked. Indeed, spinach is full of oxalic acid (a compound present in many plants) which blocks the absorption of iron and calcium. Heating the spinach releases the bound calcium, making it more available for the body to absorb.
Research suggests that steaming spinach maintains its levels of folate (B9), which may reduce the risk of certain cancers.
Cooking, by any method, significantly increases the antioxidant lycopene in tomatoes. Lycopene has been linked to a lower risk of various chronic diseases including heart disease and cancer. This increased amount of lycopene comes from heat helping to break down thick cell walls, which contain several important nutrients.
While cooking tomatoes reduces their vitamin C content by 29%, their lycopene content increases by more than 50% within 30 minutes of cooking.
Cooked carrots contain more beta-carotene than raw carrots, a substance called a carotenoid that the body converts into vitamin A. This fat-soluble vitamin supports bone growth, vision and the immune system.
Cooking carrots with the skin on more than doubles their antioxidant power. You should boil whole carrots before slicing them as this prevents these nutrients from escaping into the cooking water. Avoid frying the carrots as this has been found to reduce the amount of carotenoid.
Bell peppers are an excellent source of immune-boosting antioxidants, especially carotenoids, beta-carotene, beta-cryptoxanthin, and lutein. Heat breaks down cell walls, making carotenoids easier to your body to absorb. As with tomatoes, vitamin C is lost when peppers are boiled or steamed because the vitamin can leach into the water. Try roasting them instead.
Brassicas, which include broccoli, cauliflower and Brussels sprouts, are high in glucosinolates (sulphur-containing phytochemicals), which the body can convert into a range of cancer-fighting compounds. For these glucosinolates to be converted into cancer-fighting compounds, an enzyme in these vegetables called myrosinase must be active.
The search found that steaming these vegetables preserves both vitamin C and myrosinase and therefore the cancer-fighting compounds you can get from them. Chop the broccoli and let it rest for at least 40 minutes before cooking it too allows this myrosinase to activate.
Similarly, sprouts, when cooked, produce indole, a compound that can reduce the risk of cancer. Cooking the sprouts also causes glucosinolates to break down into compounds known to have anticancer properties.
8. Green beans
Green beans have higher levels of antioxidants when baked, microwaved, grilled, or even fried, as opposed to boiled or pressure cooked.
Kale is healthier when lightly steamed because it deactivates enzymes that prevent the body from using the iodine it needs for the thyroid, which helps regulate your metabolism.
For all vegetables, higher temperatures, longer cooking times, and greater amounts of water cause more nutrients to be lost. Water-soluble vitamins (C and many B vitamins) are the most unstable nutrients when it comes to cooking because they leach out of vegetables into the cooking water. So avoid soaking them in water, use as little water as possible when cooking, and use other cooking methods, such as steaming or roasting. Also, if you have leftover cooking water, use it in soups or sauces as it has all the nutrients leached out.