Whether a filter removes lithium depends on the technology — and, in context, there is no established health reason to remove trace lithium at all. Common activated-carbon pitcher filters such as Brita are not designed to remove dissolved lithium; reverse osmosis and distillation are far more effective. Most US tap water is already low in lithium, and the brain research is observational and mixed.
Do carbon pitcher filters remove lithium?
Activated-carbon filters work mainly by adsorbing organic compounds and chlorine; dissolved metal ions like lithium are generally not their target. An EPA study found that conventional surface-water treatment and adsorptive media were not effective at removing lithium, whereas reverse osmosis removed more than 90% (Keithley and colleagues, 2025, AWWA Water Science; DOI). That study assessed treatment-plant processes; consumer carbon pitcher filters were not tested separately, but they rely on the same adsorptive mechanism that did not remove lithium.
Which filtration methods reduce lithium?
| Method | Expected effect on dissolved lithium | Note |
|---|---|---|
| Activated carbon / conventional treatment | Not effective | Keithley and colleagues, 2025 |
| Reverse osmosis (RO) | More than 90% removal | Keithley and colleagues, 2025 |
| Lime softening | 11–54% removal (often still above 10 µg/L) | Keithley and colleagues, 2025 |
| Ion exchange (cation exchange) | Inconsistent | Keithley and colleagues, 2025 |
| Boiling | No removal | Can slightly concentrate lithium as water evaporates |
Figures are from an EPA study of water-treatment processes (Keithley and colleagues, 2025, AWWA Water Science; DOI). Distillation was not among the categories tested but, like reverse osmosis, physically separates dissolved minerals from water.
Should I filter lithium out of my water?
There is no established reason to remove lithium from drinking water for health purposes. The brain research is observational and mixed, there is no US federal limit for lithium in drinking water, and most US tap water is low: a national assessment of public-supply groundwater reported a median near 8 µg/L (Lindsey and colleagues, 2021; DOI). Decisions about filtration are personal and are not a health recommendation here. For broader context on what these water levels mean, see lithium in drinking water.
Limitations and safety
This page describes how filtration technologies generally behave with dissolved ions; it does not establish tested lithium-removal percentages beyond the EPA treatment-process figures above, and consumer pitcher filters were not tested directly. Anyone wanting to know their water lithium should test it through a certified laboratory rather than assume a filter's effect; see how to test water for lithium. Removing trace lithium is not an evidence-based health intervention. For the wider picture, see lithium and the brain and what the research actually says.
Frequently asked questions
Does a Brita filter remove lithium?
Brita and similar activated-carbon pitcher filters are not designed to remove dissolved lithium ions. An EPA study found carbon-based and conventional treatment ineffective for lithium, while reverse osmosis removed more than 90% (Keithley and colleagues, 2025). Consumer pitchers were not tested directly but use the same adsorptive mechanism that did not remove lithium.
Does reverse osmosis remove lithium?
Yes. In an EPA study, reverse osmosis removed more than 90% of lithium, the most effective method tested, though finished-water concentrations depend on blending rates (Keithley and colleagues, 2025; DOI). It is far more effective for dissolved lithium than carbon filtration.
Does boiling remove lithium from water?
No. Boiling does not remove dissolved lithium and can slightly concentrate it as water evaporates. To reduce dissolved lithium, membrane methods like reverse osmosis or distillation are more appropriate than boiling.
Should I filter lithium out of my drinking water?
There is no evidence-based reason to remove trace lithium for health purposes. The brain research is observational and mixed, there is no US federal limit, and most US tap water is already low. Filtration is a personal choice, not a health recommendation here.