Collard greens are part of the cruciferous vegetable family. This also includes bok choy, kale, broccoli, Brussels sprouts, cabbage, rutabaga, and turnips. Cruciferous vegetables are high in nutrients and low in calories.
They can play an important role in a healthy diet.
Contents of this article:
Nutritional contents of collard greens
Collard greens offer a range of health benefits.
How collard greens benefit the body
A diet rich in fruits and vegetables is associated with a reduced risk of many lifestyle-related health conditions. Increasing consumption of plant foods like collard greens has been shown to decrease the risk of obesity and overall mortality, diabetes, and heart disease. It also promotes a healthy complexion and hair, increased energy and an overall lower weight.
A low intake of vitamin K has been associated with a higher risk of bone fracture. Vitamin K consumption acts as a modifier of bone matrix proteins, it improves calcium absorption, and it may reduce urinary excretion of calcium.
One cup of boiled collard greens provides 770 micrograms of vitamin K, well over 100 percent of the daily recommended intake.
Since the 1980s, maintaining a high intake of cruciferous vegetables has consistently been associated with a lower risk of developing various types of cancer, including cancer of the upper digestive tract, colorectum, breast, and kidney.
Cruciferous vegetables have sulfur-containing compounds known as glucosinolates. Studies have suggested that they can impede the cancer process at different stages of development for lung, colorectal, breast, and prostate cancers, and possibly melanoma, esophageal cancer, and pancreatic cancer.
There is evidence that collard greens, and other green vegetables that contain high amounts of chlorophyll, can help to block the carcinogenic effects of heterocyclic amines. These substances are generated when grilling foods at a high temperature.
Diabetes and liver function
The Dietary Guidelines for Americans recommend 22.4 to 28 grams of fiber a day for women, depending on age, and 28 to 33.6 grams a day for men.
Studies have shown that people with type 1 diabetes who consume high-fiber diets have lower blood glucose levels. People with type 2 diabetes may achieve better levels of blood sugar, lipids, and insulin.
One cup of boiled collard greens provides about 8 grams of fiber.
Collard greens also contain an antioxidant known as alpha-lipoic acid. Studies suggest that alpha-lipoic acid can lower glucose levels, increase insulin sensitivity, and prevent changes in patients with diabetes that are linked to oxidative stress. It can also help to regenerate liver tissue.
It may also decrease the risk of peripheral neuropathy, autonomic neuropathy, or both in people with diabetes.
However, since most studies have used intravenous alpha-lipoic acid, it is unclear whether oral supplementation provides the same benefits. Excessively high doses of alpha lipoic acid have been shown to have adverse effects similar to those caused by too little.
Collard greens are high in both fiber and water content. These help to prevent constipation, promote regularity, and maintain a healthy digestive tract.
Healthy skin and hair
Collard greens can benefit the skin because of a high vitamin A content. Vitamin A is needed for sebum production, and this keeps hair moisturized. Vitamin A is also necessary for the growth of all bodily tissues, including skin and hair.
Adequate intake of vitamin C is needed for the building and maintenance of collagen, which provides structure to skin and hair. One cup of boiled collard greens provides over 50 percent of a person's daily needs.
Iron-deficiency is a common cause of hair loss. This can be prevented by an adequate intake of iron-containing foods like collard greens. A lack of iron in the diet can affect how efficiently the body uses energy. Collard greens, spinach, lentils, tuna, and eggs are good sources of iron.
Sleep and mood
Collard greens contain choline, which helps with sleep, muscle movement, learning, and memory. Choline also helps to maintain the structure of cellular membranes, in the transmission of nerve impulses, the absorption of fat, and the reduction of chronic inflammation.
Folate, also found in choline, may help with depression, as it can prevent an excess of homocysteine from forming in the body.
Too much homocysteine can stop blood and other nutrients from reaching the brain. It can also interfere with the production of the "feel-good" hormones serotonin, dopamine, and norepinephrine. These neurotransmitters regulate mood, sleep, and appetite.
How to incorporate more collard greens into the diet
Collard greens should have firm, deep green leaves. Smaller leaves will be tenderer and have a milder flavor. Collard greens can be kept fresh in the refrigerator.
There are many tasty, home-cooked dishes with collard greens.
Steaming collard greens for 10 minutes or less means they will still have their nutrients. Peppers, chopped onions, herbs, and spices can be used to season them.
They can be enjoyed raw in salads or on sandwiches or wraps, braised, boiled, sautéed, or added to soups and casseroles.
Another idea is to sauté fresh garlic and onions in extra-virgin olive oil until soft, then add collard greens and continue to sauté until they reach the desired tenderness.
Frying collard greens in bacon fat or lard, or overcooking them, can create a strong and bitter sulfur taste.
Adding black-eyed peas and brown rice gives a healthier version of a southern favorite.
Collard green chips
Collard green chips can be made by removing the ribs from the collard greens, tossing them in extra-virgin olive oil, and baking them at 275 degrees Fahrenheit for 15 to 30 minutes until they are crisp enough. They can be lightly sprinkled with a choice or a combination of cumin, curry powder, chili powder, roasted red pepper flakes, and garlic powder.
A handful of collard greens can be added to a favorite smoothie. This provides extra nutrients without changing the flavor significantly.
Potential health risks of consuming collard greens
People who are taking blood-thinners, such as Coumadin or warfarin, should not suddenly increase or decrease their intake of foods containing vitamin K, as it plays a major role in blood clotting.
The most important factor in achieving good health and avoiding disease is the overall diet, not a specific food item.