Brain and longevity
Lithium and brain health
Brain nutrition belongs in women’s everyday care. Explore the lithium findings behind our interest, see the data for your water supplier, and learn why Semaine is pairing lithium orotate with algae-derived DHA. Human trials, water studies, and mouse findings each have a different place in that story.
Find lithium data for your water supplier
Search a city, ZIP code, or state to explore public water-system measurements and state estimates.
Explore the water mapStart here
Get the overview, understand your water result, or explore the key studies.
- Lithium and the Brain: What the Research ShowsThe findings behind the interest in lithium and brain health.
- Lithium in Drinking Water: Understanding Your ResultYour supplier’s results, the units, and what the number can tell you.
- Lithium and Brain Health: Key Studies ExplainedThe key human and mouse findings, explained with their limits.
Explore the lithium guides
Foundations
Lithium and the Brain: What the Research Shows
Why lithium is attracting interest, and how to read the three different kinds of research.
Is Lithium an Essential Nutrient? What Is Established
Why researchers are asking whether lithium has a nutritional role.
Lithium at Different Ages: Pregnancy Through Older Adulthood
Why age and life stage change the questions researchers ask about lithium.
The evidence
Lithium and Brain Health: Key Studies Explained
Compare the studies by lithium form, study design, and what they found.
Lithium and Dementia: What the Evidence Shows
What water studies, laboratory findings, and clinical trials say about dementia.
Can Lithium Reverse Alzheimer's? Reading the Headlines
Where the reversal headlines came from, and what the study actually tested.
Lithium, Mood, and Depression: Understanding the Research
How to interpret population research on water lithium and mood-related outcomes.
How it works
How Lithium Works in the Brain: A Plain-Language Guide
How lithium interacts with signals involved in brain-cell communication and survival.
Wnt and Beta-Catenin: The Lithium Connection Explained
A plain-English guide to the signaling pathway that appears in lithium studies.
DHA and Lithium: Different Roles in Brain Research
Algae-derived DHA, lithium orotate, and the reasons behind Semaine’s proposed one-capsule formula.
Forms and dosing
Lithium Orotate vs. Carbonate: Forms, Amounts, and Safety
Understand the label, the dose, and the evidence behind each lithium form.
Lithium Orotate for Memory: What Do We Know?
The memory findings in aging mice that renewed interest in lithium orotate, and the next human-research question.
Water and diet
Lithium in Drinking Water: Understanding Your Result
Find local data and understand what a lithium water result measures.
How to Test Water for Lithium: From Utility Data to the Lab
When existing water data is enough, and when a laboratory sample is useful.
Do Brita Filters Remove Lithium? Check the Exact Model
What treatment research says about lithium removal, and how to check your filter.
Lithium in Food and Water: Understanding Dietary Intake
Where dietary lithium comes from, and why daily-intake estimates vary.
Terms worth knowing
- Micrograms per liter (µg/L)
- The amount of lithium in one liter of water. A microgram is one-millionth of a gram. Water concentration is different from a daily supplement dose.
- Milligrams (mg)
- A measure of amount. One milligram equals 1,000 micrograms. For supplements and medicines, check whether a label describes elemental lithium or the full lithium compound.
- Water reference values
- EPA’s health reference level is 10 µg/L. USGS also describes a 60 µg/L drinking-water-only benchmark. These are nonregulatory reference values, not a recommended intake or a household safety verdict.
- Measured vs modeled
- Measured results come from samples of a named water system. Modeled results are estimates. State estimates combine data across systems; the groundwater map estimates regional groundwater levels. Neither measures your household tap.
- Association vs causation
- An association means two things are linked in a study. It does not show that one causes the other. A water study can reveal a pattern worth investigating without proving a supplement benefit.
- Below the reporting limit
- The monitoring program cannot report a precise amount below this limit. For these EPA data, the limit is 9 µg/L. Below the limit does not mean zero.
Common questions
How much lithium is in tap water?
Lithium levels vary with the local geology and water source. The tool shows public water-system measurements and separate state estimates in micrograms per liter (µg/L). Cities can have several suppliers, so choose the system that serves you.
Is lithium an essential nutrient?
It is not formally classified as essential. Some researchers argue it behaves like a trace element because animal studies show effects at very low intakes, but there is no established requirement and no recommended intake. The Foundations pieces walk through both sides.
Does a water filter remove lithium?
Standard activated-carbon pitcher filters are not designed to remove dissolved lithium and generally leave it in place. Reverse osmosis and distillation do reduce it. The water and diet section covers what each method does.
What does the dementia research actually show?
Some studies have linked higher lithium levels in water with lower dementia rates; others have not. Human trials have also tested lithium, with mixed findings. A 2026 trial of lithium carbonate in older adults with mild cognitive impairment did not meet its primary outcome thresholds. The form, dose, population, and study design all matter. Our evidence guide explains those differences.
Semaine writes about the science of women's health. This guide is educational and is not medical advice.
