Vegetables you should (and shouldn’t) bother eating – from kale to carrots

Ice lettuce is ranked at the bottom because of its low nutrient density compared to other types of lettuce and leafy greens. It provides much smaller amounts of essential vitamins and minerals, such as vitamins A, C, and K, and is lower in fiber and antioxidants than its dark leafy counterparts. The green, almost white color of iceberg lettuce indicates a low concentration of phytonutrients and beneficial compounds. Although it contributes to hydration due to its high water content (about 96 percent), its nutritional benefits are limited compared to more nutrient-dense vegetables such as romaine or cos lettuce .

A healthy way to eat lettuce

Like romaine, iceberg lettuce is usually not cooked or exposed to heat. It is best used raw in the likes of salads, sandwiches and other fresh dishes to add flavor. Avoid cooking lettuce, as heat can cause it to wilt and lose its nutrients, especially water-soluble vitamins and mild antioxidants.

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Vegetables and vitamins

Although we only need them in small amounts, vitamins are key to keeping our bodies functioning properly. They strengthen our immune system, strengthen our bones and keep our skin healthy. Our bodies cannot make them, so we need to get them from our diet.

“Vegetables are great sources of essential vitamins, especially vitamins A, C, K, folate and E,” explains Dr Maria Traka, head of food and nutrition at the Quadram Institute. For example, vitamin A helps us see things in dim light, while vitamin K helps blood clot so that wounds heal.

Unfortunately, popping a multivitamin isn’t really a quick fix if you don’t eat enough vegetables. “Getting nutrients from whole foods increases nutrient absorption and reduces the risk of overdosing,” which can be toxic, he says. Over the long term, too much vitamin A can weaken our bones, too much vitamin D can damage the kidneys and heart, and too much iron can be fatal.

“In addition, vegetables contain other beneficial components such as polyphenols, carotenoids and phytochemicals,” which are not available in supplements, Dr Traka says. Studies suggest that this reduces the risk of many diseases, including cancer, cardiovascular disease, degenerative eye diseases and osteoporosis.

Vegetables and fiber

Fiber is a carbohydrate found in plants. “It works to push other materials into the intestines to promote regular bowel movements, improve bowel movement and can relieve constipation,” Dr Traka explains.

It helps fill us up, which can help prevent overeating and weight gain, improve blood sugar control, and thus protect against Type 2 diabetes, and feed our microbiome, so it’s good for gut health, he says. Fiber has also been shown to protect against inflammation, heart disease and colon cancer, Dr Traka adds.

Per 100g, peas (6g), potatoes (4g), Brussels sprouts (3.9g) and broccoli (2.6g) are some of the richest vegetables.

Vegetables and carbohydrates

Sweet, high-carb vegetables are often demonized for being higher in calories than leafy greens and salads. However, potatoes, sweet potatoes, carrots, parsnips and sweet corn are still nutritious. It is a starchy food that is full of fiber and vitamins.

“They provide unique benefits that low-carb vegetables may not provide,” explains Dr Traka. They provide a fast and stable source of energy. The fiber in these vegetables promotes satiety, helps control weight and helps regulate digestion and blood sugar levels.”

Cooking vegetables

Fresh vegetables are obviously packed with nutrients, but frozen can be just as nutritious or, in some cases, superior.

For example, research suggests that frozen kale is high in antioxidants, while frozen broccoli is high in B vitamins. This is because the vegetable is frozen at its peak, which limits its nutritional value. However, frozen vegetables may lose some vitamins during cooking, as they release more water during cooking.

The picture is mixed about tinned. “Some water-soluble vitamins such as B vitamins and vitamin C can be lost during canning or enter the surrounding water,” Dr Traka explains. “Also, check the label and choose canned vegetables with no added salt or sugar.”

When it comes to cooking, root vegetables covered in honey and roasted in the oven for an hour are obviously delicious. Unfortunately, less cooking is often better, as it prevents nutrients from being lost, explains Dr Traka.

“Lightly steaming is better than boiling,” he says, “because boiling vegetables in a lot of water causes the B vitamins and vitamin C to escape into the water. When frying or grilling, avoid topping vegetables with oil.” or butter as it adds unnecessary calories.

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The Science of Plant-Based Nutrition published by DK on June 27