Recent studies suggest that cruciferous vegetables like kale are some of the healthiest foods one can enjoy eating and at the same time depend on to maintain good health and prevent disease. Kale leaves are tender and mildly sweet. They have a pleasant pungent odor and some bitter peppery flavor that goes well with strongly flavored other foods. It can be incorporated in many recipes for salads, stews, soup, and more.
Cruciferous vegetables like kale, broccoli and brussels sprouts are often dubbed as “supervegetables” because they are nutrient-rich and they help promote health while preventing chronic disease. Experts recommend eating one to two cups of these vegetables at least two to three times in a week to benefit from their rich nutrient content.
Kale provides an excellent source of vitamins A , C, and K, as well as manganese. It is also very good source of vitamin B6, tryptophan, calcium, potassium, and copper, and a good source of vitamins E, B1, B2, and B3 protein, folate, phosphorous, iron, and magnesium.
Antioxidant Benefits. Kale is a rich source of antioxidants, or substances which fight free radicals, that are responsible for the development of many chronic diseases, including cancer, heart disease, diabetes and stroke.
One cup of kale leaves provides the body with sulfur-containing phytonutrients in large amounts: vitamin A (206% of daily value), vitamin C (134% of DV), and vitamin K (684% of DV).
Carotenoids like lutein and zeaxanthin in kale promote eye-health and prevent cataracts and age-related macular degeneration.
Vitamin K is necessary for a variety of body functions, such as normal blood clotting and bone health. It helps limit damage of cells in the brain and it has been found to play a role in the treatment of Alzheimer’s disease. According to a study in the American Journal of Clinical Nutrition, a diet rich in vitamin K can reduce one’s overall risk of developing cancer.
Other antioxidants in kale include flavonoids, such as quercetin and kaempferol, which are known to fight inflammation and reduce the risk of heart disease and diabetes.
Kale is rich source of minerals like calcium, potassium, copper, sodium, iron, phosphorus, and manganese. Potassium plays a vital role as a component of the cell and body fluids, helping to control blood pressure and heart rate by balancing the effects of sodium. Manganese acts as a co-factor for superoxide dismutase, an antioxidant enzyme, while iron is involved in red blood cell formation.
Anti-cancer Benefits. Aside from antioxidants already mentioned, kale and other cruciferous vegetables are a rich source of sulfur-containing phytochemicals called glucosinolates and by- their breakdown products, such as isothiocyanates and indole-3 carbanol. Eating a diet rich in these substances have been associated with a reduced risk of cancer. Studies suggest that regular consumption of kale, broccoli, and other vegetables in this family reduces the risk for lung, breast, colorectal, and prostate cancers.
Weight Reduction. Kale is a low calorie vegetable (36 calories/cup cooked kale) that is also low in fat and cholesterol. It is high in fiber, which promotes maintenance of healthy weight. Aside from these, kale is a good source of alpha-linolenic acid (ALA), a building block for omega-3 fatty acids. One cup of cooked kale provides 100 grams of omega-3 fatty acids, which play a role in preventing heart disease.
How to Select & Store
Kale is available throughout the year but you will find it at its best during the months of November to March. Exposure of kale to light frost enhances its quality. The lower leaves may be picked progressively at harvest time or the whole plant may be cut at the stem and then packed in bundles.
Select kale with moist firm stems and dark colored leaves. Buy fresh leaves that are crispy and brilliantly colored. Kale should be placed in a cool section since warm temperature will make it wilt and negatively affect its flavor. The leaves should look fresh, not wilted, with no signs of yellowing, browning, or small holes. Select smaller sized kale leaves since these are more tender and with milder flavor than larger sized leaves.
Borecole, or kale, is highly perishable and it should be used quickly after harvest. If it has to be stored in the refrigerator, set the temperature below 35 F and at high humidity level to keep it fresh for about five days. Avoid washing the leaves because it will encourage spoilage. Place kale in a plastic storage bag and remove as much air from the bag as you can. If it is stored longer, its flavor becomes more bitter.
- Zelman, K. The Truth about Kale. WebMD.
- Magee, E. The Super-Veggies: Cruciferous Vegetables. WebMD.
- Higdon J, Delage B, Dashwood R, et al. Cruciferous Vegetables and Human Cancer Risk: Epidemiologic Evidence and Mechanistic Basis. Pharmacol Res 2007; 55(3): 224-236.
- WHFoods. Kale. http://whfoods.org/genpage.php?dbid=38&tname=foodspice