As well as playing a key role in helping blood to clot, vitamin K is critical in preventing certain age-related conditions. Researchers in California found inadequate K can lead to cardiovascular disease, bone fragility, and arterial and kidney calcification. A one-cup (250-mL) raw serving of any of the leafy greens here has at least your daily requirement of K, with kale providing more than six times your needs, dandelion greens five times and Swiss chard about three and a half times.
Mustard greens and kale help lower cholesterol. Here’s how: The liver uses cholesterol to make bile acids, which aid in fat digestion. When bile acid binds with the fibre of these greens, it gets excreted from the body-which means the liver has to use up more cholesterol to make new bile acid and, voilà, cholesterol levels are reduced. According to a U.S. study in Nutrition Research, steamed mustard greens and kale do this to a greater extent than raw.
Preserve vision health
Leafy greens-in particular kale, dandelion, mustard greens and Swiss chard-are good sources of carotenoids lutein and zeaxanthin, which help filter high-energy light that may cause eye damage. Lutein and zeaxanthin reduce discomfort caused by glare, decrease the risk of cataracts and increase how far you can see.