Chock-Full of Bok Choy

There’s an old trope that children hate eating vegetables, especially ones like broccoli or Brussel sprouts. But broccoli and Brussel sprouts are good for you, so parents insist that they be cleared entirely from the plate. After all, you can never have too much of a good thing, right?

Vegetables like broccoli and Brussel sprouts are cruciferous vegetables belonging to the genus Brassica. This genus of plants also includes cabbages, mustard, cauliflower, turnip, kale rutabaga, canola and bok choy, to name a few. Studies suggest that diets rich in cruciferous vegetables help protect individuals against cancers as well as cardiovascular and neurological diseases.

What makes these vegetables so healthy? It seems that most of the benefits of cruciferous plants come from chemicals called glucosinolates. These are sulfur-containing compounds that help protect plants from pests. When ingested by humans, these glucosinolates are broken down into a variety of different beneficial chemicals that circulate throughout the body.

While the glucosinolates in cruciferous vegetables may make them seem like miracle super foods, it turns out you can actually have too much of a good thing. At extremely high levels, glucosinolates can damage the liver and block the uptake of iodine by the thyroid. The thyroid uses iodine to produce hormones that  help regulate how the body uses energy. Without these hormones organ function slows, mental processes become muddled and, if untreated, things can progress to a coma and even death.

A literal food coma is the last thing one expects from eating vegetables. It certainly wasn’t what an 88-year-old woman living in New York expected when she decided to eat 2-3 lbs of raw bok choy, or Chinese white cabbage, each day for several months. She believed it would help her control her diabetes, because vegetables = healthy. Months of cabbage, however, led her to a hospital complaining of extreme lethargy and the inability to walk or swallow. She had to be intubated and slipped into a coma. Thankfully, she was nursed back to health and was eventually discharged.

So the next time your child protests when offered vegetables, recognize the slight validity of their claim and then make them eat their greens anyway. It’s gonna take a boat load more of raw broccoli before the risks outweigh the benefits.

Brian Rutter, PhD, is the cofounder of Thing in a Pot Productions and a postdoctoral researcher in plant biology at Indiana University. Subscribe to our newsletter to receive our “Things About Things – Odd Facts About Plants” and video production tips in your inbox every month!

Works Cited:

Chu, M., & Seltzer, T. F. (2010). Myxedema coma induced by ingestion of raw bok choy. New England Journal of Medicine, 362(20), 1945-1946.

Dinkova-Kostova, A. T., & Kostov, R. V. (2012). Glucosinolates and isothiocyanates in health and disease. Trends in molecular medicine, 18(6), 337-347.

Traka, M. H. (2016). Health benefits of glucosinolates. Advances in botanical research, 80, 247-279.