There’s no denying kale’s enormous nutritional benefits. Kale is one of my favorite green foods. But how do you prepare kale for smoothies and is it better to use raw kale or to cook kale before putting it in a smoothie?
Kale is a cruciferous vegetable and loaded with life-changing nutrients. But like most other cruciferous vegetables, eating a large amount of raw kale can inhibit the uptake of iodine by the thyroid gland.
When raw kale is chewed and digested by your intestinal bacteria, the bacteria release substances called goitrogens that increase the need for iodine when consumed in small amounts and can damage your thyroid gland.
This is a problem for the over 30 million Americans who are currently dealing with thyroid disease. If you are one of them, you need to know about the downsides of eating raw kale and what you can do about it.
The key here is how much you eat and how often. That’s why I am a big advocate of rotating your greens when making smoothies on a weekly basis.
Raw kale also contains oxalic acid which may bind to minerals like calcium and magnesium in the body creating crystals that can damage tissues and cause inflammation.
So what do you do about goitrogens and oxalic acid?
Don’t worry, there’s a simple method to solve this problem. If you are like me and don’t want to give up the numerous benefits of adding kale to your diet, keep reading…
Cook kale before adding to smoothies
So how do you minimize goitrogens and still get the needed benefits of adding kale to smoothies?
Cook kale for smoothies. I’m not talking about cooking all the nutrients out of the kale. A nice light steaming or blanching of your kale can reduce the goitrogens to about one-third of the original value.
Of course, the longer you cook your kale, the fewer goitrogens (and the fewer nutrients) will be present in the kale. Boiling kale for about 20-30 minutes reduces almost all of the goitrogens from kale. So it’s a balance. Luckily kale has an abundance of nutrients so it’s unlikely you’ll cook away all of the nutritional qualities.
Cooking also decreases the oxalate content of kale and other similar vegetables.
Preparing kale for smoothies
When I cook my kale for smoothies this is the process I follow. I am always short on time so if you are busy like me, this process only adds a few extra minutes to your smoothie prep time.
Step 1. Add about a cup of water to your saucepan. Turn on high heat to bring close to a boil. This method is a cross between boiling and blanching.
Step 2. Pull a whole head of kale out of the refrigerator. I do this in batches and freeze whatever I don’t use so I don’t have to repeat this step every time (time saver again).
Step 3. Once the water is close to boiling, reduce heat to medium. Add the kale (you can chop it or just throw the whole head in there depending on the size of the saucepan you are using.
Step 4 (optional). Add some coconut oil and mix the kale around so you get all of the kale submerged in the hot water. I add coconut oil to my smoothies any way so this skips a step for me. Coconut oil has a high smoke point and helps keep the kale from sticking to the pan too.
Step 5. After 3-5 minutes max, the kale should be ready to add to your smoothie. Pour the water from the saucepan and replace it with cold water to cool it down.
Step 6. I add kale as the starting base to my smoothie with water. With water filled in the blender cup, add the cooled kale to it. Then add the rest of your ingredients and blend away!
You can, of course, mix this process up as you see fit! But just make sure you don’t cook the kale too long. How long should you cook the kale before adding to your smoothie? No more than 7-10 minutes. Just enough to get some of the oxalates and goitrogens out of it.
Remember, if you have a perfectly normal thyroid and adequate iodine consumption, eating kale and adding it to your smoothies in small amounts won’t be a big issue. Also, rotate your greens so you don’t eat kale every single day. Mix it up and this will reduce your needed concern about goitrogens and oxalates.
Now over to you, do you add kale to your smoothies? How to you prepare kale for smoothies? Raw or cooked? I’d love to hear your comments.