Kale is, and has been, the new “it” vegetable for a while now. I think it was also the “it” vegetable a few decades ago, then went away and came back. Anyone who wore bell bottoms in the 90’s thinking it was so new, only to see pictures of mom rocking the same thing in the 70’s knows that sometimes happens.
But now, we have a few articles – like this one on “The Dark Side Of Kale” – discussing the potential for kale and other cruciferous vegetables – including broccoli, bok choy, cabbage, cauliflower, collard greens, and brussels sprouts – to cause problems with our thyroid. Here’s the gist of the article:
A lot of people, even President Obama and Kevin Bacon, love kale. Kale is awesome. But, then a reporter from the times (a young, healthy 40-something) found out she had hypothyroidism. Apparently, a Google search lead her to lots of information about how the kale she juiced every morning and some other cruciferous vegetables have been linked to hypothyroidism. Researchers from Oregon State University explain that this can happen because certain compounds in the vegetables break down to some compounds which can interfere with the body’s ability to produce thyroid hormone and other compounds that can compete with iodine for uptake by the thyroid (the thyroid needs enough iodine to function normally). But, the good news is, the risk of developing hypothyroidism from too much raw cruciferous veg appears to be troublesome mostly in the presence of an iodine deficiency. The article also notes a few other things you can do to prevent this problem…
1. Cook your kale – cooked kale loses many of its goitrogenic properties (those qualities that cause thyroid issues) when it’s cooked.
2. Eat seaweed to make sure you’re getting enough iodine
3. Add a Brazil nut every now and again – Brazil nuts have plenty of Selenium, and Selenium can help support normal iodine levels.
4. Alternate between cruciferous and non-cruciferous vegetables.
Afraid of kale now? Don’t be. As one of the interviewed experts points out, the poison is in the dose. Eating a few servings of raw kale, broccoli, or brussels sprouts per week is fine. Juicing several pounds of kale or spinach everyday may put you at risk. (Besides, you shouldn’t be juicing all your vegetables anyway, because you lose all the good fiber in them when you do that).
So, does kale cause hypothyroidism? No, not usually. But it might, if you eat over 3 pounds of it raw everyday. If you’re not doing that, feel free to keep enjoying your kale and broccoli – it is a good source of important nutrients like fiber, B vitamins, and iron.