They say too much of anything isn’t a good thing. But it’s safe to say that vegetables are the one exception, right?
Well, according to rumblings in health circles, perhaps not. Word on the street is, eating too much kale can actually lead to weight gain. Yep, kale — as in the superfood that health fanatics have been raving about for the last five years. Is nothing safe anymore!?
Apparently, going overboard on the vegetable can affect your iodine production, which can cause your thyroid to become enlarged. And when your thyroid is out of whack, it leads to a host of health issues — includingweight gain. But can something that’s so good for us really be so, well, bad for us? We consulted Amodrn’s resident nutritionist Emma Cronin to find out. Here’s what she had to say:
Kale (along with other cruciferous vegetables such as broccoli, brussel sprouts, bok choy, cauliflower, and cabbage) is goitrogenic, which means that it contains a substance called thiocyanate — which can interfere with iodine production if eaten raw. Iodine production is essential to a healthy functioning thyroid. So yes, in theory, raw kale can affect thyroid production. However, in practice this is really only a concern for anyone who already has hypothyroidism (an under functioning thyroid), or individuals who are already iodine deficient, which can include people on a restrictive diet such as vegans or vegetarians. And it will only affect people with a thyroid disorder due to iodine deficiency, not autoimmune hypothyroidism (the latter accounts for nearly 90% of cases).
If you cook your cruciferous vegetables, the heat deactivates the goitrogens. So in reality, if you have a healthy thyroid or autoimmune hypothyroidism, you would need to eat a LOT of raw kale or other cruciferous vegetables to really affect your thyroid hormone production.
So, how much is too much? Well, so far, research into the quantities has been limited to small studies or cooked cruciferous vegetables. However, the only known case of someone developing hypothyroidism from cruciferous vegetables was an 88-year-old woman who ate 1-1.5kg of raw bok choy every day. Now we wouldn’t recommend these quantities daily of any food group. So in reality, kale lovers should be feeling pretty safe!