Panic! Are cruciferous vegs killing my thyroid? I’m taking a stand on this issue.

A reader, Shawna, wrote us an email with tons of capitalized sentences and exclamation points, saying, “Hey! I’ve been doing green smoothies for a few years now! And I’m hypothyroid! Help–am I killing my thyroid?”

My customer support wrote me that people constantly write us “freaking out” about a widely circulated article on the internet saying that cruciferous vegetables essentially damage your thyroid gland. Crucifers include broccoli, kale, cabbage, and cauliflower.

People are susceptible to fear and paranoia–which are antithetical to empowerment and faith. I’ve written about this in Ch. 1 of 12 Steps to Whole Foods, but I need to take a stronger stand, since it’s Top Five (questions I am asked, via email and everytime I speak in public).

As with food-combining theories (D’Adamo, etc.), or the idea that too many of one green food is “toxic” (Boutenko), or the idea that oxalates in greens harm us (another dubious internet-circulated claim)… reaction is like that line from Jerry Maguire, “Show me the money!”

My variation on that quote is, “Show me the data!”

Evidence that cruciferous vegetables are phenomenally powerful anti-cancer foods is voluminous. They also reduce bad estrogens; this is desperately needed by Americans, as we’re daily bombarded with endocrine disruptors (“bad estrogens”). David Wolfe, in fact, says his favorite supplement of 2011 is Indole-3-Carbinol (I3C), which is an extract of the crucifers. I’ve been taking it myself.

The evidence that one compound in crucifers may have deleterious effects? It’s limited and sketchy at best.

If we can isolate one compound (of dozens, maybe 100 or more) in green foods, and say that Compound X has Effect Y on Gland Z, how do we know that Compounds A, B, and C don’t have mitigating effects on Effect Y? How do we know that the profoundly healing properties of Compounds D, E, and F in that same food don’t work together synergistically with Compound X? The mountain of evidence that vegetables prevent disease suggests that foods are far more than the sum of their parts. Science still has little understanding of why plant foods are powerful, although in general, scientific communities like to break things down into parts and explain phenomena inductively. Let’s back up and use some deductive reasoning.

The “articles” on the internet (read: people saying stuff–let’s not give them undue credit by calling them articles) claim that LARGE AMOUNTS can damage the thyroid and increase the need for iodine. The entire American diet does both of those things–first, damage the thyroid, and second, increase the need for iodine (for instance, we eat salt stripped of iodine in virtually all our foods– or that refined salt has chemical isolates of a toxic form of iodine put back in). So I’m highly skeptical of how any researcher isolated the “goitrogen” factor. Somebody please show me where that’s been done.

Pick on the REAL bad guys here. Are we really going to flog cabbage and broccoli, when 95% of Americans are eating nuggets boiled in grease made of dozens of disease-infested chicken “parts” that if you looked at them each separately, you would wrinkle your nose and throw it in the garbage? And the same 95% are drinking tubs full of brown chemical liquids infused with carbon dioxide that contain absolutely no food?

About Shawna’s question. Me, too–I’ve been hypothyroid AND I drink green smoothies daily. But in my case, it’s been 17 years, not 3. My thyroid was all but destroyed because of nuclear fallout at the Nevada test site in the late 60’s when I was a baby, drinking highly radioactive milk from cows who ate the radioactive fallout on the grass even hundreds of miles away.

Read the rest of my answer on the topic of goitrogens and thyroid (too long for the blog). Or just come back every day, and I’ll post the rest in installments…..the next two days I have cool 3-min. videos for you!


18 thoughts on “Panic! Are cruciferous vegs killing my thyroid? I’m taking a stand on this issue.

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  1. I too always come across articles on various websites on topics I look up and find contradicting or confusing information. For instance, I was googling Small Intestinal Bacterial Overgrowth (doing some dubious self-diagnosis here) and read on one website that eating raw foods was a big no-no although I wasn’t sure if it meant until your condition gets better or permanently. Which seems to go against the whole raw foods notion that raw foods provide necessary enzymes needed for a healthy digestive system. Needless to say, it can get pretty confusing.

  2. I’m reading Donna Gates book on Body Ecology Diet. She is for food combining, are you telling me that their isn’t any scientific facts to support that food combining is necessary or a good thing? I hear a lot of different people saying you should do food combining so you don’t get gassy or bloated & have better food digestion. So, is this true or not? I’m hoping not,because I think it’s a pain in the neck to have to worry about food combining. Also, another question, again I hear people talking about you should eat for your blood type. If I eat for my blood type B, there wouldn’t be much for me to eat! Is this true or false? There is just so much confusing stuff out there. But you are the only one that I truly trust so I’m waiting for your answers. Thank you!

  3. Leslee, please read about this in the Intro to 12 Steps. 🙂 That’s a long topic! I think there’s little or no actual data–Dr. Joel Fuhrman does the best job of debunking the whole D’Adamo theory.

  4. For those people eating meat, I believe that food combining is important. It is harder to digest steak and a potato etc. etc. It can sit inside you for a very long time!

  5. Interesting. I too wondered about Eat Right For your Blood type also and like Leslee I’m also a Type B. Yes, it was so discouraging to read that all the foods I considered okay and “healthy” in moderation like say the avocado which I occasionally toss in my smoothies is not only bad for me but reacts like a POISON. I’m trying harder to limit meat but all chicken for type B’s they claim has a lectin in it that too reacts as a Poison not to mention a laundry list of foods. When I have the money to order all your 12 steps info I look forward to reading this. Sometimes I feel that the more smoothies I drink and really eat cleaner and more organic and even some alkaline water I’m actually heavier!! Why? I know I need to pick up the exercise but even when I rarely exercised I never ate as good as I eat now but the fat was much less. Grrr. I will NEVER give up my green smoothies so all I can think of is to keep using more greens than fruit but pretty much already do this. Should I keep the bananas out for awhile too?

    Thanks Robyn! 🙂

  6. I have to say that I don’t believe our bodies were meant for “food combining” or “eat for your blood type.” Our ancestors didn’t sit around and obsess about which combinations of food they should eat, so why should we? They just ate whole, nourishing plant foods on a daily basis. If it worked for them, it works for me. 🙂

  7. Autumn – I was surprsied not to lose more weight when I started doing lots of GS, but after many months I also decided to quit gluten – I dropped 10 pounds in about three weeks, maybe four. It melted off. And my energy went up. For me it was the missing piece. Doesn’t mean it would be for you, but thought I’d pass that along for your consideration. (It also eliminated my migraines by about 95%, wicih is the real reason I gave it a try – the weight loss was a nice extra.) I also gave up dairy at the same time, so hard to say which food was most responisible. Since I feel so much better, I’m sticking with doing without both of them!

  8. Our ancestors have passed onto us problems. My ancestors all died of cancer. Fruit also ferments when sitting in our gut with meat.

    1. Even if I don’t subscribe to making “rocket science” of food with ridiculous food-combining contortions, I do agree with a couple of combining principles:

      1. If it causes you, personally, a problem, to eat two foods together, then don’t.
      2. Meat and fruit are a bad combo.

      (I’ve said all this in the Intro to 12 Steps, and on this blog before. Thanks for the reminder, Diane.)

  9. Re: Mgm and Megan, Thank you both. I stopped Gluten recently and drink Rice Milk but still occasionally have a little cheese(dairy) but I’m getting there. Thanks!

  10. Leslee, also see Donna’s latest version of Body Ecology, how at the end she says she AGREES with food combining, blood typing, etc. but then gives about 20 points she DISAGREES with. At the end of the day, it’s THEORY and I would not hang my hat on it.

  11. I just started doing green smoothies a few weeks ago. I haven’t made any other major changes to my diet (which isn’t really so bad anyhow). My skin, which used to get dry and itchy, is a lot more supple and I have noticed my jeans fit a bit better. I am considering going on a gs “fast” for a few days.

    I am hypothyroid and have read a lot about avoiding raw cruciferous veggies so am avoiding things like kale and arugula. I kind of think I am missing out on something vital. Is this a legitimate concern?

    1. Catherine, I do not believe that avoiding cruciferous vegetables is a good idea (I am hypothyroid too though it is managed with diet and small dose of bioidentical). I think someone said it and it gets passed around on the internet and among some holistic practitioners. That said, if you trust your practitioner and testing revealed an issue with goitrogens (I doubt there is such a test), you will of course want to test that. The cruciferous family of vegetables is a powerhouse.

      1. Hi, I can only speak from my experience with regard to the cruciferous vegetables. I love smoothies and started having them daily a few years ago, using kale or spinach for my greens. Within 3 weeks my tongue started swelling, I felt as if I was choking all the time, my eyebrows began to disappear, my skin was dry and I had other hypo symptoms. I felt quite ill. I was borderline hypothyroid prior to that but never really had any problems. I didn’t know of the goitrogenic link with these vegetables. Anyway, I saw a thyroid specialist here in the UK and he confirmed that the goitrogens triggered the problem. I omitted them and now use organic romaine lettuce and cucumber instead with no further problems. So I’m not sure. I’m not an expert but I would say to anyone who is hypo, if you are having these vegetables and you feel fine, then that’s okay. But if you do notice any problems, try omitting them to see if you improve, like I did. Health and healing to all.

        1. Yes, Liss. Me too. I can’t even tolerate goitrogens to much if they are cooked. I only eat them sparingly. I have found that fruit is my favorite thing and really agrees with me. Everyone is different. I have a friend who eats kale all the time and is fine.

  12. I know this is way past the time of the post, but I came here from a google search, so I’m assuming others will too. I can only give my experience. My thyroid has already been destroyed (proved by ultrasounds)because of Hashimoto’s. Thus, I am on Cytomel (T3). I take it twice a day. I was starting to do kale smoothies in the morning, but when I did, my medicine wouldn’t work. I know this because my symptoms of hypothyroidism come out as painful fibromyalgia. I must be rendering my medicine useless because I am making the smoothie before it goes throughout my system. Again, this is just me. I may have strong symptoms when I try raw kale because of my unique chemistry. Now perhaps I could cook it, cool it or freeze it, THEN make a smoothie.

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