Health BenefitsDark green leafy vegetables are, calorie for calorie, probably the most concentrated source of nutrition of any food. They are a rich source of minerals (including iron, calcium, potassium, and magnesium) and vitamins, including vitamins K, C, E, and many of the B vitamins. They also provide a variety of phytonutrients including beta-carotene, lutein, and zeaxanthin, which protect our cells from damage and our eyes from age-related problems, among many other effects. Dark green leaves even contain small amounts of Omega-3 fats.
Perhaps the star of these nutrients is Vitamin K. A cup of most cooked greens provides at least nine times the minimum recommended intake of Vitamin K, and even a couple of cups of dark salad greens usually provide the minimum all on their own. Recent research has provided evidence that this vitamin may be even more important than we once thought (the current minimum may not be optimal), and many people do not get enough of it.
- Regulates blood clotting
- Helps protect bones from osteoporosis
- May help prevent and possibly even reduce atherosclerosis by reducing calcium in arterial plaques
- May be a key regulator of inflammation, and may help protect us from inflammatory diseases including arthitis
- May help prevent diabetes
Vitamin K is a fat-soluble vitamin, so make sure to put dressing on your salad, or cook your greens with oil.
Almost Carb-FreeGreens have very little carbohydrate in them, and the carbs that are there are packed in layers of fiber, which make them very slow to digest. That is why, in general, greens have very little impact on blood glucose. In some systems greens are even treated as a "freebie" carb-wise (meaning the carbohydrate doesn't have to be counted at all).
Note on oxalates: Some greens contain substances called oxalates which may bind some percentage of the calcium in the greens. More information on oxalates from the World's Healthiest Foods