Kale Deemed Not Poisonous? Assessing the Facts and Theories Behind Thallium and Cesium

The lesson here is to question everything and eat kale in moderation

Thallium levels in kale might not be as harmful after all.

Last week, we reported that kale might not actually be healthy for you because it contains trace amounts of the heavy metals thallium and cesium. Much talk has circulated around the information cited in this article, by molecular biologist Ernie Hubbard, and some people are skeptical of the facts behind this science — meaning, kale might actually be OK after all.

The Centers for Disease Control and Prevention explains that the human health effects from exposure to low environmental levels of thallium are “unknown.” CDC scientists sampled thallium levels in people’s urine and found “measurable levels,” saying:

“Finding measurable amounts of thallium in urine does not imply that the levels of thallium cause an adverse health effect. Biomonitoring studies on levels of thallium provide physicians and public health officials with reference values so that they can determine whether people have been exposed to higher levels of thallium than are found in the general population.”


What we can conclude from this kale debacle is that too much of something is never a good thing. On that note, feel free to enjoy kale — just do it in moderation to be on the safe side.