Trends in foods come and go, and I feel like kale is one of those foods which has become trendy at times with popular variations of healthy kale smoothies suddenly exploding everywhere over the internet on health and fitness blogs and social media pages alike. Regardless of whether it’s a trend or not, I’d say kale remains one of the most nutrient dense foods available to people in supermarkets and can certainly play a key role in providing many minerals within your diet.
Trendy or not, if you can replace unhealthier foods with more nutrient dense ones and feel more satiated, you are making a better choice for your body and this will help to contribute to a better overall sense of wellbeing by keeping yourself well nourished.
The Nutrient Dense Kale
Kale is a cruciferous vegetable rich in vitamins, vital nutrients and glucosinates (sulfurous compounds). When cooked, glucosinates break down into metabolites which are substances that affect your metabolic rate and help trigger certain enzymatic reactions in the body. These metabolites have the ability to help fend off infections from microorganisms in the intestines with a study from 2009 and 2012 suggesting a higher intake of cruciferous vegetables (not just kale!) can help to decrease the risk of cancers.
Kale is very rich in vitamins K, A and C with 130g or 1 cup of kale contributing to 1180%, 98% and 71% of your recommended daily allowance (RDA) of these vitamins respectively. 100g of kale also contains around 490mg of potassium, another mineral which is important for cellular function within the body. Since it can be hard to reach the RDA of potassium, which is about 4700mg per day then adding kale to your meals can help to ensure you consume enough potassium.
Major Health Benefits of Kale
Listed above are only a brief summary of some of the powerful effects eating kale can have. Here, I’m going to delve into more detail on the health-boosting properties kale can provide!
#1 – Kale is an Antioxidant Powerhouse
Kale contains two of the three main antioxidants vitamins: vitamin C and beta-carotene (which is converted by the body into vitamin A). These help to prevent oxidative damage to our cells which can accelerate inflammatory processes and cellular ageing.
Insufficient consumption of antioxidants can lead to oxidative stress and chronic inflammation, both of which are risk factors in the development of cancer. Oxidative stress, in particular, has been linked to neurocognitive disorders such as Alzheimer’s and Parkinson’s disease. Kale can provide the antioxidants to help prevent the onset of such neurocognitive diseases.
#2 – Kale is Anti-Inflammatory
Most people have heard of omega fatty acids, primarily omega 6’s and omega 3’s. What many don’t know is that if you consume a high ratio of omega 6’s to omega 3’s, overtime then it can put your body in a chronic inflammatory state. The problem is that so many processed foods contain high levels of omega 6’s, it is hard to maintain this balance. Kale is a good anti-inflammatory food because it contains a ratio of 1:1.3 omega 6’s to omega 3’s, helping to reduce the negative effects people experience when consuming highly processed foods rich in omega 6’s.
#3 – Kale Detoxes your Body
Alright, so we all know about the health teas on the market which cost a fortune and are marketed as ‘detox teas’, but what if I told you that kale can do the same job?
Thanks to the glucosinates in kale, kale actually helps to remove and eliminate toxins from your body. Glucosinates are used to make isothiocyanates which are compounds that aid in the detoxification of your body at a cellular level.
#4 – Kale Contains Cancer Preventing Compounds
These compounds called glucosinates I just spoke of, well they have cancer-preventing properties, with some even having cancer-treating properties. But it’s not just kale that contains high levels of glucosinates – it’s all cruciferous vegetables.
A review of research published in the October 1996 issue of the Journal of the American Dietetic Association showed that 70% or more of the studies found a link between cruciferous vegetables and protection against cancer.
Glucosinates and isothiocyanates help to rid the body of carcinogenic compounds, which are substances capable of causing cancer in living tissue. During chewing and digestion, these cancer-fighting compounds break down and form biologically active substances which prevent cancerous cell growth. These biologically active substances formed are isothiocyanates, thiocyanates and indoles.
Reasons isothiocyanates, thiocyanates and indoles that prevent cancer from spreading include:
- Being able to inactivate carcinogens
- Containing antiviral and antifungal properties
- Containing anti-inflammatory properties
- Protecting cells from DNA damage
- Inducing cell death (apoptosis) in cancerous cells
- Inhibiting tumour blood vessel formation
- Inhibiting tumour cell migration
This trio of cancer-fighting compounds has been shown to reduce colon, bladder, breast, prostate and ovarian cancer risks. These have all been found to have a decrease in relation to the routine consumption of kale.
#5 – Kale Supports Cardiovascular Health
One of the main problems in the arteries people would like to avoid is atherosclerosis. This is the deposition of fatty material on the inner arterial walls which over time if the arteries clog up completely, can lead to heart attacks and strokes unless dealt with by the body. Plaque formation is required for clogging to occur within the arteries, but since kale is such a rich source of antioxidants and anti-inflammatory nutrients, it helps to combat atherosclerosis, reducing the risk of cardiovascular diseases. The nutrients in kale help to deal with the free radicals formed by chronic inflammation and chronic oxidative stress, both factors which can speed up the process of atherosclerosis.
That’s not all though, kale has the ability to lower cholesterol, although cholesterol isn’t actually the problem. What is useful though, is that it can increase the ratio of HDLs (high-density lipoproteins) to LDLs (low-density lipoproteins). Kale contains a large range of fibre-related nutrients which can bind to bile acids produced in our liver. Our body needs to replace these bile acids, and one way it can do that is by breaking down cholesterol. Studies on kale intake show that an increased consumption of kale correlates to a drop in total blood cholesterol and LDL levels whilst HDL levels increase. Eating raw and cooked kale has been shown to provide these cardiovascular benefits, although steamed kale appeared to show greater benefits. The good news for those who like juice their vegetables is that those who drank 5 ounces (around 150ml) of kale juice a day for 12 weeks found similar benefits.
Nutrient Profile of Kale
Just so you get an idea of how nutrient dense kale is, here is a table from whfoods (world’s healthiest foods)!
The vitamin K content of kale is one that is particularly astounding. Vitamin K plays a critical role in the formation of blood clots (which aren’t bad!) that prevent excessive bleeding at sites of injury.
How to Store Kale
Some key points to note when storing kale:
- Try not to wash kale before storing as exposure to water encourages it to spoil.
- When storing, try and remove as much air from the bag as possible unless it is already packaged (in which case you can’t).
- Try and consume within 5 days once opened.
- Refrigeration is the ideal storage method as the cool temperatures help to prevent loss of vitamin C, vitamin B6 and carotenoids. These nutrients are susceptible to heat, so cooler temperatures will help to retain these nutrients better.
Preparing and Cooking Kale
Unless you’re lucky enough to buy your kale prechopped in a bag, I’d suggest preparing kale in the following way:
- Rinse kale under cold running water.
- Chop leaves into half-inch slices (1.25cm).
- Chop stems into quarter-inch slices (0.625cm).
- This will allow for the kale to cook quickly and evenly.
Science has shown that there are 3 key guidelines in retaining nutrients whilst cooking:
- Use minimal necessary heat exposure.
- Cook for the minimal amount of time required.
- Minimalise the amount of contact between the food and the cooking liquid.
In one study, 60% of glucosinates in kale were lost after 5 minutes of boiling.
For this reason, I’d suggest steaming kale (and almost all other vegetables) to retain the maximum amount of nutrients. By preparing kale like above and using lemon juice, garlic, olive oil and salt and pepper, you can quickly prepare some kale in this 5 minute recipe!
If you just want to cook it and eat it simply:
- Fill the steamer with about 2 inches (5cm) of water
- Fill the steamer with kale
- Turn the hob on medium heat for 5 – 10 minutes
And voilà! You’ve cooked your kale! After, you can figure out what heat intensity and duration is required to make sure your kale is not under or overcooked.
One way my mum likes to cook kale is to sauté it with bacon lardons (small strips of fatty bacon). It tastes really good, and uses virtually no liquid other than the bacon fat.
- Add 25g bacon lardons to a large pot.
- Add chopped garlic and onions.
- Add kale, stir and place the lid on top.
- Leave for up to 10 minutes when cooked.
Did you know kale was this nutrient dense? Will you start eating kale? Let me know down below!