It’s time for some nutrition 101. We always get told to “eat lots of leafy green vegetables”. But – what exactly are we talking about, and why should we be chowing down on them all the time?
Leafy Greens is a flexible term that applies to a broad range of vegetables that yep, you guessed it, have leafy, frondy bits that we can eat. A non-exhaustive list of leafy greens includes:
- Rocket aka aragula
- Lettuce varieties eg cos, iceberg, romaine, red leaf, butter lettuce
- Beet greens
- Mustard greens
- Collard greens
- Swiss chard / Rainbow chard
- Turnip greens
- Chinese broccoli
- Choy sum
- Bok choy
- Broccoli and broccolini
- Herbs like parsley, mint, coriander, basil, etc.
…and the list goes on.
Leafy greens are a diverse bunch botanically; from the soft lactuca sativa (ie lettuce) varieties, grassy spinach, punchy beet leaves, all the way through to the thick, crunchy brassicas like kale, cabbage and broccoli.
Why Eat Them?
With their diverse botanical backgrounds, there exists a wide range of reasons why you should be eating leafy greens (and also this is why you should eat a variety of them). Here are a few key points.
Lettuce, despite being often thought of as a bit of a “nothing” food, is actually quite a good source of vitamins. One cup of shredded cos or romaine will give you a significant dose of vitamin A (as beta-carotene, which is converted to vitamin A in the body) and vitamin K, plus a moderate amount of vitamin C and folate.
- We don’t talk much about Vitamin K, but it’s quite an important one for our bodies, it helps with blood clotting and wound repair and helps to reduce the risk of osteoporosis – what a star! You can read more about Vitamin K here. Note that Vitamin K is a fat-soluble vitamin, so make sure you dress your salad with a good glug of extra virgin olive oil for maximum benefits.
Dark Leafy Greens
Spinach, chard and beet greens provide a similar array of beneficial vitamins to lettuce. They are also a moderate source of essential minerals including iron, magnesium, calcium, potassium and manganese.
- A caveat on the iron content in spinach though, as it’s often touted as an iron-rich superfood – it’s not sky high, as you might think! A 60 gram serving of spinach (which is about 2 cups of raw spinach leaves) will give you about 10% of your recommended daily iron intake. Add a vitamin C-rich food to your spinach to help your body absorb the iron, as plant-based iron is more difficult for your body to absorb than iron from animal sources. A squeeze of lemon juice or some sliced tomato are easy (note cooking can also help improve the absorption of plant-derived iron, see more info on the types of iron here).
Lettuce, spinach and chard/beet greens are also excellent sources of substances called flavonoids. Flavonoids are plant chemicals which can act as an antioxidant in the body (i.e. they are able to neutralise the effect of harmful particles called free radicals that are linked with cell damage and disease). The concentration of flavonoids differs between all the leafy greens, however rest assured that all varieties of these beautiful leaves are donating some of these goodies to you.
- I think it’s always best to try to get your antioxidants (and other nutrients) from whole foods as opposed to supplements. Many supplement studies report inconclusive findings as to the benefits of taking single antioxidant compounds (see a brief overview here), but it’s more widely acknowledged that eating fresh produce provides health benefits (see another short discussion here).
Not all of the brassicas are super leafy and not all of them are green, but you can certainly count some toward your beneficial leafy greens intake.
- The brassica vegetables (broccoli, cauliflower, kale, cabbage, brussels sprouts), also sometimes called cruciferous vegetables, are a nutritional powerhouse. Like the other greens, they provide a good dose of vitamins (B vitamins, folate, vitamin A and vitamin C) and offer amounts of minerals including calcium, potassium, iron and copper. A cup of broccoli will give you your recommended daily intake of vitamin C – too easy!
- Another awesome benefit of the brassicas is that they are an excellent source of sulfur-rich compounds called isothiocyanates, which facilitate natural detoxification processes in our bodies. Research indicates that consumption of vegetables rich in isothiocyanates assists in the clearance of toxins by the liver helping to clear out potential carcinogens and free radicals (see here and here for some examples of the research in to this).
So there you have it! A heap of good reasons to fill up your shopping basket with leafy greens of all varieties. What’s your favourite way to prepare your greens? Share your tips with me!