CRUCIFEROUS VEGETABLES AND YOUR
THYROID
Raw cruciferous vegetables like broccoli, cauliflower, kale,
bok choy, and cabbage have caught a bad rap, mostly
because of compounds within them that are believed to
disrupt thyroid function. The compounds in question are the
glucosinolates, which are the ones that, when chewed raw,
create beneficial sulforaphane.
The issue is that glucosinolates temporarily inhibit
uptake of iodine into the thyroid, which is not good because
iodine is a required element for thyroid hormone
production. In the fifties, when iodine deficiency was
widespread, eating otherwise healthy cruciferous vegetables
led many to hypothyroidism, and the government thus
mandated that all table salt be iodized. Problem solved,
right? At the time, yes. Today, however, health-conscious
eaters are moving away from iodized salt to non-iodized
alternatives like sea salt, and ironically we are again at risk
for iodine deficiency. To combat this, it is important to
consume sea vegetables (dried nori or kelp noodles are top
sources) and other foods rich in iodine such as scallops,
salmon, eggs, and turkey. Three ounces of shrimp or baked
turkey breast each provide 34 micrograms of essential
iodine. That’s about 23 percent of the recommended daily
intake (RDI). One quarter ounce of seaweed, for
comparison, provides 4,500 micrograms of iodine—3,000
percent of the RDI.
In the absence of an iodine deficiency, cruciferous