Collard Green and Kale

Kale and collard greens occupy similar niches in a healthy diet. Both belong to the family of
cruciferous vegetables, which also includes broccoli and cauliflower, and both count towards the 1.5 to
2 cups of green vegetables the USDA recommends you consume each week. Collard greens and kale
make for very nutritious additions to your diet, but differ in their micronutrient content.
Fat-Soluble Vitamins
Kale and collard greens both provide rich sources of two fat-soluble vitamins, A and K, although kale
boasts a higher vitamin content. Eating 1 cup of chopped collards provides you with 2,400
international units of vitamin A, as well as 183.9 micrograms of vitamin K. An equivalent serving of
kale contains significantly more vitamin K, at 547.4 micrograms, as well as 10,302 IU of vitamin A.
However, consuming large amounts of vitamin K without first informing your doctor can prove
dangerous for some individuals. Because vitamin K plays a role in blood clotting, high levels of vitamin
K in your system can affect the efficacy of blood thinners, such as warfarin. Talk to your doctor about the safety of consuming kale on a regular basis if you suffer from clotting disorders or take anti-coagulant medications, and consider consuming collards as a more moderate source of vitamin K.
Water-Soluble Vitamins

Collard greens and kale also boost your intake of water-soluble vitamins. Both types of greens contain a range of B vitamins, including vitamin B-1, riboflavin, niacin, folic acid and vitamins B-5 and B-6. These nutrients support your metabolism and help maintain healthy skin and hair. Kale and collards differ slightly in their vitamin C content. A 1-cup serving of collard greens contains a moderate 12.7 milligrams of vitamin C -- 17 percent of the recommended daily intake for women, or 14 percent of the RDA for men, according to the University of Maryland Medical Center. Kale contains 80.4 milligrams of vitamin C, the entire daily recommended intake for women, or 89 percent of the RDA for men.
Minerals
Eating collard greens or kale boosts your intake of essential minerals, including potassium, phosphorus, copper, manganese, selenium and zinc. Both greens also provide some calcium, although kale proves richer in calcium, boasting 90 milligrams per cup, compared to 52 milligrams in a cup of collard greens. Kale also contains more iron than collard greens, offering 1.14 milligrams of the mineral per 1-cup serving -- much more than the 0.07 milligrams found in an equivalent serving of collard greens. If you rely on dark leafy greens as vegetarian sources of iron and calcium, choose kale over collards.
Preparation Tips
Since both kale and collards contain large amounts of fat-soluble vitamins A and K, you should consume these vegetables with fat. Adding a small amount of oil to your greens allows your body to properly absorb these vitamins so you can reap the full nutritional benefits of your greens. Chop your kale or collard greens into slices, then lightly coat with olive oil and steam until tender. If plain steamed kale or collards sound boring, try