Note: I wrote this post in 2012, when kale was the new superfood, and I was eating it a lot – too much, it turns out.
Ahh kale, everyone’s favorite green, nutrient-dense veggie.
In my health coaching course, we all got a little obsessed with kale. Regular kale. Curly kale. And my very favorite, Cavolo Nero.
In fact, I even wrote a post last December extolling the virtues of this vintage veggie – sharing my favorite breakfast recipe for using kale!
But alas, I’ve been taught another important lesson (again):
Moderation and variety are important in all things – even healthy foods!
A recent trip to the doctor (because of unusual tiredness, poor digestion and low appetite) revealed that my thyroid was very underactive.
And then some internet research turned up a possible cause – some foods are goitrogenic, meaning that they suppress thyroid function. And what did I find on that list of foods, but my beloved kale!
Could it be true? Could eating too much kale be the cause of my low thyroid?
Maybe you’ve seen those pictures from old medical books of people with huge Goiters on their throat (they made an impression on me when I was a kid!) As I understand it, a goiter is an extreme swelling of the thyroid. Similarly, goitrogenic foods suppress the action of the thyroid, which can cause goiters in extreme cases, or less severly, can contribute to low thyroid (hypothyroid).
Common goitrogenic foods include: cabbage, collard greens, bok choi, KALE, cauliflower, broccoli and brussels sprouts.
Yep, loads of very healthy foods on that list.
Should you stop eating these types of veggies?
No! Cruciferous veggies (like the ones listed above) are super healthy and packed with good nutrients.
My problem (I think) is that I was eating way too much kale – no variety, no moderation. I was also eating a lot of it raw in green smoothies (some sources indicate that eating these veggies cooked deactivates the thyroid-suppressing effect.)
So how much kale was I eating?
A lot. Too much. I went from never tasting kale in my life, to eating it almost daily – sometimes twice per day.
Was too much kale the cause of my low thyroid?
I don’t know … yet.
But when I think about what changed between last year (normal thyroid reading) and this year (low thyroid reading), the two major differences are: 1) higher stress levels and 2) lots of kale!
So I’m trying an experiment. I’m reducing those types of foods in my diet, getting back into meditation/yoga, and will retest in a few months. I’ll report back to let you know the results!
So the moral of the story is:
Moderation. Variety. In everything, even healthy foods.
Don’t eat the same thing everyday.
Experiment with new veggies and grains.
And listen to your body – it will tell you if your diet is working for you
[Update: See my follow-up post about the kale-thyroid connection]