Is Your Kale Smoothie Harming Your Thyroid?


Kale is the superfood of the 21st century. It has reached superstar status among health nuts and everyday folks. It has become a snackable chip and the darling of morning smoothies. Just when everything seemed to be on the up-and-up, someone had to pop a needle into the green balloon.

In an opinion piece in the New York Times, Jennifer Berman, a health food fanatic for over 25 years, learned that her thyroid problems may be the result of consuming too many cruciferous vegetables, including kale and broccoli.

How does one go about consuming too much kale?

By drinking it! Which is exactly what happens when you buy a $500 Vitamix and employ it daily to gulp down copious amounts of nutrients that you otherwise have to chew on for hours to ingest.

Kale, when consumed in very large quantities, may lead to hypothyroidism, according to experts cited in this NPR report. Other curciferous vegetables that share this similar trait include broccoli, brussel sprouts, cabbage, cauliflower, turnips, and bok choy. Don’t worry, eating these veggies several times a week is perfectly fine, and recommended for healthy people. It’s the overdoing with smoothies that may cause problems. If you can, try to eat your veggies, not drink them.

Are you a kale junkie?

  • Michael J Marino

    With all the amazing benefits of juicing, I would hardly consider this to be true.

    • JoshuaTreeGal

      Sad to say it is true. I have thyroid problems and told this to my doctor at my last visit. He did not believe it either and said he would check into it via medical journals. To my surprise he called me back a few days later to confirm and told me to go easy on the raw Kale and other cruciferous vegetables. Cooked is fine.

  • Carrie

    How much is toooo much? I put a half a cup in my smoothie

  • CiCi

    Everything is bad for you. Sick of the critics. You get one thing bad out of your diet and replace it with something that is good then that turns out to be bad. You can never win. Do what makes you feel happy and healthy.

    • Dan

      Ignorance is bliss huh? :)

      Look it up-this is actually true and the information of cruciferous veggies and thyroid is out there

  • Audrey

    Don’t worry. I read the link, and you can neutralize the effects in two ways: cooking it and eating Brazil nuts. Also, the health issues described in this post are highly unlikely to affect to a healthy adult; they only usually occur when you have iodine deficiency. I quote,”Increased exposure to thiocyanate ions from cruciferous vegetable consumption or, more commonly, from cigarette smoking, does not appear to increase the risk of hypothyroidism unless accompanied by iodine deficiency.”

    • Carol H

      Brazil nuts are super high in selenium, which makes eating them an easy way to overdose on selenium. One ounce (about a small-med. handful) contains more than 5x the DV for selenium and is over the “upper intake level” for daily selenium intake. Limit intake to a couple nuts a day, max.

  • Fooducate

    The key takeaway here is not to overdo anything. Not even kale.

    • Alyssa B

      I agree. Anything is going to do you some harm when you start eating way more of it than your body was ever meant to eat, healthy or otherwise. Even drinking too much (I’m talking wayyyyyy too much) water can be a problem.

    • SixCatFaerie

      Reminds me of a study I read about years ago. They fed rats nothing but watermelon and when the rats died from eating a watermelon a day they tried to say that watermelon was bad for you. So, yes, too much of even a good thing can be bad.

    • Dale

      I actually read that article before I read this post. What the author said was that she was diagnosed with this condition and looked up on the web what foods she should eat or avoid. She was surprised to find out that cruciferous veggies were contraindicated for her condition.

      While I understand that you had a point to make I think it’s irresponsible to cite one individual’s habits as an exemplar.

      • michael

        That’s the kind of critical thinking we need to employ when dealing with people who write for a living and must constantly one up themselves to get our attention. Sound thinking on you part. Well done.

        • Dale

          Thank you Michael. As a freelance writer myself I fully understand the pressures of writing a regular column. However, that doesn’t mean that one person (even another writer) should be isolated as an example to prove a point.

      • Andy Bent

        It’s unfortunate that writing and journalism have become so sensationalized, based out of necessity to grab readers attention fast enough before they leave the page, that writers (think they) must use such ploys, based off of currently conjecture opinions, that they themselves haven’t even fully researched prior to posting.

        This includes not only the article titles, which are bad enough, but the stylized syntax in the article itself utilized to grab the readers attention and make them question their habits, even if they have not taken part in the supposed problem. Reference: The top post in these comments “How much is toooo much? I put a half a cup in my smoothie”, which makes obvious that this, and many readers, will jump to assumptive conclusions without doing further critical research outside of the partially, if not fully bunk, article, that is if they even finished reading the article at all.

        TL;DR : Journalists and writers who write articles such as this one: Shame on you. Work to improve the quality of your writing, not the quantity, and especially not the sensationalism. Do your research before hitting that “post” button.

  • Vegana

    This is bullshit

  • Mike

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    Take a look let me know what u think