🪶 Disclosure & Statement: I assist Rosbacher and Römer Brunnen in their Taiwan market development. Römer Brunnen belongs to Germany’s Heilwasser lithium-containing water classification, which this article mentions. All discussions in this article regarding “lithium, brain, Alzheimer’s” are objective discussions of 2025 Harvard research and European dietary culture, and do not constitute medical advice. Yankner team’s research is currently primarily completed in mouse models, with human clinical trials just beginning. Please do not purchase lithium supplements on your own; consult professional physicians for health-related decisions.

TL;DR — August 2025 Harvard Bruce Yankner team’s research published in Nature shows: lithium may be a fundamental metal for brain function, with amyloid proteins potentially acting like “sponges” absorbing free lithium from the brain. Europe’s century-old Heilwasser “healing water” tradition has long used natural mineral water containing trace lithium for daily wellness. This is something European society has practiced for a century, which modern molecular biology is only just beginning to explain.

A Scientist Who Spent 35 Years Completing His Own Theory

In the early 1990s, Harvard University’s Professor Bruce Yankner was still a young neurologist. In his laboratory, he conducted an experiment that was technically extremely difficult at the time—dripping purified amyloid protein onto nerve cells in culture dishes.

The result: nerve cells began dying en masse.

This discovery later became known as the “Amyloid Hypothesis”—laying the foundation for the next 30 years of Alzheimer’s research. Almost all new drug development worldwide for combating dementia focused firepower on the goal of “clearing amyloid protein plaques from the brain.” Eli Lilly, Biogen, Roche—pharmaceutical giants invested hundreds of billions of dollars cumulatively in related drugs. In 2023–2024, the first new drugs based on this theory were officially approved by the U.S. FDA—Leqembi (July 2023) and Kisunla (July 2024).

The story up to this point follows smoothly—a typical “basic science leads to medical breakthrough” narrative.

But in August 2025, Yankner himself published another paper in Nature journal: amyloid proteins may not be direct culprits. They’re more like “sponges” that absorb a trace element overlooked for a century from the brain—lithium.

It’s the same person who, 35 years later, completed the hypothesis he had established back then.

Why is this story important? Because it opens a new perspective—and this perspective coincides with a century-old European tradition.

A Century-Old Anatomical Paradox

To understand why Yankner would return to re-examine his own theory, we need to hear about a paradox that has troubled the neuroscience community for a long time.

Every time neurologists dissect deceased patients’ brains, they see an extremely abnormal phenomenon: some elderly people who were mentally sharp, had excellent memory, and completely normal cognitive function while alive, but when their brains were opened after death, they were densely packed with amyloid protein plaques—as severe as those in patients with severe dementia.

If amyloid proteins were truly the only culprit, this phenomenon makes no sense.

This paradox stumped the neuroscience community for 30 years. Until Yankner’s team’s 2025 research found a possible answer.

The New “Sponge Hypothesis”

Their team spent ten years overcoming the technical challenge of “measuring trace metals in the brain” and discovered an extremely counterintuitive truth:

The brain relies on naturally occurring “lithium” elements to maintain normal memory and cognitive function. When amyloid proteins begin accumulating in the brain, these plaques tightly bind and absorb free lithium.

The more plaques, the more available lithium gets drained from the brain.

(Must clarify first: “lithium as an essential human trace element” remains a frontier hypothesis in 2026. Mainstream nutrition textbooks worldwide have not yet listed lithium among essential elements at the same level as zinc, iron, copper. Yankner’s research pushes this line forward significantly, but it’s still considerable distance from “textbook consensus.”)

This perfectly explains the century-old paradox:

  • If a person’s brain has high lithium reserves to begin with, even if plaques develop and absorb some lithium, remaining lithium is still sufficient to maintain neural function—so cognitive function remains intact.
  • Conversely, if lithium reserves were already marginal, once plaques begin accumulating and frantically competing for lithium, when the brain’s defenses collapse, memory collapses with it.

What we previously thought was the pathogenic culprit may be a “thief” that causes loss of crucial trace elements.

The research team also conducted a key validation experiment: they deliberately depleted lithium from mouse brains—resulting in immediate cliff-like drops in memory even without other pathological changes, with Alzheimer’s pathological processes dramatically accelerated.

Next they identified a special compound called “lithium orotate” that can evade amyloid protein hijacking. When this formula was used on Alzheimer’s mice, pathological changes were halted and lost memories began reversing.

This therapy is currently in preparatory stages for human clinical trials in the United States.

Why Does This Relate to European Mineral Water?

Back to our main topic—mineral water.

When Yankner’s research was first published, a very interesting reaction emerged in European water culture circles: “Haven’t we been drinking this for over a hundred years already?”

This statement is somewhat exaggerated, but historically accurate.

As we introduced in our first article, Germany’s Heilwasser (healing water) legal classification—currently about 55 water sources have this certification, among which lithium-containing water is a sub-category clearly recognized by tradition:

German Heilwasser Lithium WatersLithium ContentTraditional Claims
Bad Mergentheimer Albertquelle13.0 mg/L (global highest record)Nervous system & metabolic balance
Hirschquelle1.3 mg/LSame as above
Bad Vilbeler Römer Brunnen1.1 mg/LMineral supplementation, digestion
Heppinger Extra0.84 mg/LDigestive system & metabolism
Staatlich Fachingen0.77 mg/LGastric hyperacidity

Lithium content > 0.5 mg/L is Germany’s legal threshold for defining “lithium-containing water”—this standard didn’t appear in 2025, it has existed in Germany’s pharmaceutical legal system for over fifty years.

In other words: Europeans didn’t have molecular mechanism evidence that “lithium repairs memory,” but they had already noticed the special properties of lithium-containing water through experience and wrote it into legal classifications. Italy’s Vichy Catalan (lithium 1.3 mg/L) follows the same traditional practice.

This is the core of what this article wants to say—when folk practice has been doing something for a hundred years, modern molecular biology is just beginning to validate it.

History unfolded this way:

  • 1925: Bad Vilbel recognized by Hessen state as healing spring source
  • 1881: Spain’s Vichy Catalan discovered by Dr. Furest
  • 1930: Römer Brunnen 287-meter artesian spring drilled
  • 1955: Römer Brunnen receives German national Heilwasser certification
  • 1990: Yankner publishes amyloid hypothesis
  • August 2025: Yankner publishes lithium-amyloid mechanism paper (Nature)

That is—from Heilwasser legal classification establishment to molecular mechanism validation, 70 years passed. Tradition arrived first, science arrived later.

This isn’t to say “tradition is always right.” Rather—when folk practice and modern research point in the same direction, it’s worth stopping to take a look.

But—Many “Buts”

At this point, I must switch to serious mode. This story has many aspects requiring caution.

1. Harvard Research Currently Primarily in Mice

Yankner team’s key experiments were completed in mouse models. The miracle of lithium orotate reversing memory currently only occurs in laboratory mice. Human clinical trials are just beginning preparation—from mice to humans, drug mechanisms could be completely different. History has too many cases of “effective in animals but failed in humans.”

Moreover, Alzheimer’s field has an ironic fact—nearly all amyloid protein mouse experiments over the past 20 years looked beautiful, but entering human Phase III clinical trials, the vast majority failed. This is why Yankner himself would return to re-examine this line. Whether lithium orotate will be effective in humans won’t have first readings until around 2028–2030.

2. “Lithium in Drinking Water” vs “Medicinal Lithium” Huge Gap

Dosage RangePurpose
Heilwasser lithium water0.5–13 mg/LDrinking water intake, ~0.1–3 mg per glass
Observational study beneficial threshold≥ 15 µg/L (drinking water)Epidemiological observation
Harvard study effective dose (mice)~0.1–0.2 mg/dayAnimal experiments
Bipolar clinical lithium treatment600–1,200 mg/dayDrug treatment

Medicinal dosage is over 1,000 times higher than drinking water intake. In other words: lithium in mineral water is completely not medicine, it’s daily trace levels.

Another often-overlooked difference is chemical form. The “lithium orotate” used in Yankner team’s mouse experiments is a specific organic lithium compound formulation, which the research team specifically chose for its ability to evade amyloid protein hijacking. Natural mineral water lithium is mostly inorganic forms (lithium carbonate, lithium sulfate, etc.), and their absorption rates, brain entry efficiency, and protein interactions are completely different from lithium orotate. Treating “drinking mineral water for lithium” as a cheap version of “taking lithium orotate supplements” is chemically invalid.

3. Partial Epidemiological Observations Support, But Not Causal

Over the past 20 years, scattered research has observed that “regions with higher lithium in drinking water have lower suicide and dementia prevalence rates”—such as Denmark (Kessing 2017), Japan (Muronaga 2022), Texas USA (2018) county data. But this is correlation, not causation—regions with good water quality may simultaneously have other health factors.

4. Groups Unsuitable for Lithium Supplementation

  • Hypertension, cardiovascular disease (watch sodium intake)
  • Kidney disease, diuretic users (lithium accumulates with impaired kidney function)
  • Thyroid disease (lithium interferes with thyroid)
  • Pregnant women, nursing mothers (high doses have neurodevelopmental risks)

5. Taiwan Regulatory Red Lines

Taiwan’s Food Safety and Sanitation Management Act Article 28 clearly states that food (including mineral water) cannot make therapeutic claims. Therefore—

  • Imported lithium-containing mineral water in Taiwan cannot claim “prevent dementia,” “brain enhancement,” “improve Alzheimer’s”
  • Product labels can only state objective mineral content (like “naturally contains lithium 1.1 mg/L”)
  • Any language approaching therapeutic implications violates law

This is why this article uses conservative language like “may,” “research shows,” “why” throughout—this is cultural discussion and knowledge dissemination, not product recommendation.

6. “Europeans Drank for a Hundred Years” Isn’t Safety Proof

This story uses “tradition arrived first, science arrived later” as narrative backbone, but one thing must be clear—a century of European drinking experience doesn’t equal safety for everyone, in all situations.

First, these Heilwasser lithium water long-term users were mostly local regional, specific lifestyle population subsets (like German middle-class families regularly visiting Bad Vilbel spas). Their diet, exercise, overall nutrition, medical accessibility differ from modern Taiwan urban life and cannot be directly transferred.

Second, modern environmental lithium exposure sources are completely different from a hundred years ago—battery industry, electronic products, industrial emissions all increase environmental lithium burden. So the observation “European elderly drank for a hundred years without problems” may not be replicable in 2026 Taiwan.

Then What? How Should I Think About This?

For me—I would understand it this way:

Yankner’s research doesn’t give me a reason to drink some water. It gives me a perspective to re-understand “water” as a thing.

The past thirty years’ health discourse mainstreamed “anti”—antioxidant, anti-inflammatory, anti-free radical, anti-aging. We treat the body as a battlefield, all aging and disease elements as enemies, buying all supplements that can “defeat.”

But Yankner’s research reminds us: the brain isn’t a battlefield, it’s an ecosystem. Neurodegenerative disease occurrence often isn’t because the brain suddenly gained foreign monsters, but because it lost tiny foundations that originally existed and quietly supported operation.

From this angle, Europe’s century-old Heilwasser tradition isn’t so mysterious—it’s not treatment, it’s replenishment. Not radical therapy, but gentle daily practice. When Europeans drink these waters, they don’t treat them as medicine, but as daily recovery of trace elements from a geological stratum, an ancient spring, ten thousand years of sediment.

In the next decade, lithium-brain relationship research will continue developing. Perhaps Yankner’s hypothesis will be validated like his own amyloid hypothesis back then, perhaps it will be revised or overturned. This isn’t what this article cares about.

What I care about is—our understanding of water can evolve from “quenching thirst” to “building relationships with a place”.

On this evolutionary path, the first article covered German mineral water culture, the second taught label reading, the third covered dining pairings. This piece is the final turn on this path—from external to internal, from sensory to molecular, from drinking water to knowing your own body.

Epilogue: When Heilwasser Meets Yankner

Before doing this brand, I never thought “water” could connect to neuroscience.

But after three months digging through Bad Vilbel historical materials, examining SGS Institut Fresenius analysis reports, tracking Yankner’s papers, I see a beautiful timeline:

1925, Bad Vilbel recognized by Hessen state as healing spring source. 1930, Römer Brunnen 287-meter deep well gushes first artesian mineral water. 1955, this well receives German national Heilwasser certification. 2025, across the Atlantic at Harvard laboratory, discovery that brain function may need lithium.

For an entire century, nobody could connect these two storylines. European spa tradition was tradition, Harvard molecular biology was molecular biology—two worlds, two languages.

But after 2025, these two lines began intersecting.

Not saying tradition necessarily wins, nor that science must validate tradition. But when you walk into a European spa town with century-old history (Bad Vilbel, Vichy, Spa), watching those locals who insist on drinking mineral water—you begin wondering: what do they know that we haven’t figured out yet?

Next time you pick up a lithium-containing mineral water bottle and drink it—it’s not medicine, nor those small print nutrition facts. It’s an incompletely decoded message of geology and time.

Science is still catching up to tradition. Tradition is still waiting for science.

And you and I happen to live in the year these two lines intersect.

Footnotes・Sources

Harvard Yankner Research (2025)

Epidemiological Supporting Research

  • Trace lithium levels in drinking water and risk of dementia: a systematic review. PMC11364728 (2024)
  • Lithium in Portuguese Bottled Natural Mineral Waters—Potential for Health Benefits? PMC7696288

European Lithium Water Data (Continued from First Article)

Regulatory & Safety References

Media Reports & Commentary

Series Conclusion

This is the fourth piece in the “Mineral Water Culture” series, and the temporary conclusion of this topic.

Four pieces down—

From a piece of land to a molecule, from a meal to a person’s brain.

Thank you for walking through these four pieces with me. See you at the next topic.