(NewsNation) — It’s common knowledge that tea is great — for stress, sleep or inflammation — but a new study suggests it might prevent lead consumption, too.
Brewing tea removes charged atoms of heavy metals from water, effectively filtering out contaminators such as arsenic, lead and cadmium, according to Northwestern University research published in ACS Food Science & Technology.
According to Benjamin Shindel, the study’s first author, the tea leaves absorb heavy metals the longer they are steeped. When tea bags or leaves are removed prior to drinking, so are the metals.
Data estimates that the process of making tea can remediate roughly 15% of lead from water, even if the lead concentration is incredibly high.
“I’m not sure that there’s anything uniquely remarkable about tea leaves as a material,” Shindel told Northwestern Now. “They have a high active surface area, which is a useful property for an absorbent material and what makes tea leaves good at releasing flavor chemicals rapidly into your water.
“But what is special is that tea happens to be the most consumed beverage in the world,” he clarified.
Which tea absorbs the most metal?
Researchers tested black, green, oolong, white, chamomile and rooibos teas — both loose-leaf and commercially bagged.
So, what’s the perfect tea to absorb metal? The team’s results point to finely ground black tea in a cellulose bag for the most benefit.
More than any other factor, time spent steeping is pivotal to metal removal. Steeping overnight, rather than for just a few minutes, resulted in a much more purified product.
“Some people brew their tea for a matter of seconds, and they are not going to get a lot of remediation. But brewing tea for longer periods or even overnight — like iced tea — will recover most of the metal or maybe even close to all of the metal in the water,” Shindel explained.
