Dark green veggies, which is a food group that includes leafy greens such as kale, spinach and dandelion greens, should make regular appearances in your diet, and USDA dietary guidelines recommend 1.5 to 2 cups weekly. Consuming 2 cups of raw leafy greens, or 1 cup of cooked greens, counts as 1 cup toward this goal. Kale, dandelion and spinach all differ slightly in their nutrient content, but they all come packed with nutritional value and make smart additions to any health-conscious diet.
Kale, spinach and dandelion greens all serve as excellent sources of vitamin K. Your body uses vitamin K to activate a range of proteins, including proteins needed for bone development, as well as lung and heart cell growth. It's also essential for blood coagulation, and healthy vitamin K levels ensure that your body can form blood clots needed to prevent excessive bleeding. A single 2-cup serving of raw spinach, kale or dandelion greens provides your entire recommended daily intake of vitamin K.
Kale, spinach and dandelion greens all provide beneficial copper, a mineral important for your metabolism. Copper activates an enzyme, called cytochrome c oxidase, that allows your cells to convert nutrients into useable energy. It also plays an important role in tissue health, by supporting collagen maturation, a process important for strong healthy blood vessels and bones. You need 0.9 milligrams of copper daily. A 2-cup serving of raw kale contains 2 milligrams, while equivalent servings of raw spinach and dandelion greens contain 0.1 and 0.2 milligrams, respectively.
Add a 2-cup serving of raw dandelion greens, spinach or kale to your diet and you'll also consume your daily recommended intake of vitamin A. Your body can use vitamin A to maintain healthy skin cell function, which not only benefits your skin's appearance, but ensures that your skin forms a strong barrier against infection. It also helps you make red blood cells -- the cells that carry oxygen to your tissues -- and helps your eyes function properly, especially at night.
Lutein and Zeaxanthin
All three foods also provide a generous amount of lutein and zeaxanthin. Dandelion contains the most lutein and zeaxanathin, at 15 milligrams per serving, while kale and spinach contain 11 and 7.3 milligrams per serving, respectively. This provides most or all of the 12 milligrams of lutein and zeaxanthin recommended daily by the American Optometric Association. Both lutein and zeaxanthin aid in eye function, and filter light as it enters your eye to protect the delicate tissues inside your eyes from damage. A diet rich in lutein and zeaxanthin promotes long-term visual health and reduces your risk of macular degeneration and cataracts.
- USDA ChooseMyPlate: How Many Vegetables Are Needed Daily or Weekly?
- HealthAliciousNess: Nutrition Facts Comparison Tool
- Linus Pauling Institute: Copper
- Linus Pauling Institute: Vitamin K
- Linus Pauling Institute: Vitamin A
- Linus Pauling Institute: Carotenoids
- American Optometric Association: Lutein and Zeaxanthin
Sylvie Tremblay holds a Master of Science in molecular and cellular biology and has years of experience as a cancer researcher and neuroscientist. Based in Ontario, Canada, Tremblay is an experienced journalist and blogger specializing in nutrition, fitness, lifestyle, health and biotechnology, as well as real estate, agriculture and clean tech.