Lithium (Low-Dose): Benefits, Forms, Dosing, and Side Effects

Table of Contents

• Current view (reviewed 20 October 2026)
• Key safety points
• Brad's videos on this topic
• Overview
• Forms and Bioavailability
• Evidence for Benefits
• Recommended Dosing
• Safety and Side Effects
• Drug Interactions
• Dietary Sources
• References

Current view (reviewed 20 October 2026)

Brad says better clinical evidence is needed before making strong recommendations about low-dose lithium supplements, and for now caution is warranted (Brad, 9 Sep 2025). Lithium is not an established nutrient: there is no recommended daily intake for it anywhere and no recognised deficiency, and the interest in low-dose lithium comes mainly from animal studies and from population studies of lithium in drinking water, which can't show cause and effect (Brad's current guidance, 9 Oct 2026). A study in Nature found much lower lithium in the brains of people with mild cognitive impairment or Alzheimer's disease, and in mice lithium orotate almost completely blocked plaque and tau build-up while lithium carbonate had no significant effect, but the work relied heavily on mouse models (Brad, 9 Sep 2025). The human trials so far have been small, most used prescription lithium at doses far higher than a supplement contains, all the dementia and memory trials enrolled people who already had memory problems, and lithium orotate itself has not yet been tested in a completed randomised human trial (Brad's current guidance, 9 Oct 2026). The best dose for protecting the brain is not known, and too much lithium can have serious side effects; low doses are likely safer, but risks still exist (Brad, 9 Sep 2025). People who live where drinking water is rich in lithium, or who eat a lot of high-lithium foods, may already get enough (Brad, 9 Sep 2025).

Brad's videos on this topic

• 9 Sep 2025, Low-Dose Lithium CRUSHES Dementia & Brain Aging?: a Nature study links low brain lithium to Alzheimer's disease, and in mice lithium orotate blocked plaque build-up where lithium carbonate did not; Brad wants better clinical evidence before recommending a supplement. Superseded on the human trials: his October 2026 guidance stresses that they are small, mostly used high-dose prescription lithium, and have not yet tested lithium orotate.

1. Overview

Lithium is a trace mineral, but it is not an established nutrient: no lithium deficiency disease has been defined in humans ^[23]. Drinking-water studies and a few small trials suggest low doses of lithium may affect mood, suicide rates and dementia risk, but none of this evidence is conclusive ^{[9, 12, 14, 16]}.

At high doses, lithium is a prescription drug for bipolar disorder ^[2]. Prescription lithium carbonate is 18.8% lithium by weight ^[25]. The treatment range for blood lithium is 0.8 to 1.2 mEq/L, and toxic levels (at least 1.5 mEq/L) are close to it ^[27]. The liquid form is lithium citrate syrup ^{[2, 7]}. At these doses lithium has adverse effects on the kidneys, thyroid gland and parathyroid glands, so people taking it need periodic blood tests to monitor these organs ^[3].

Low-dose supplements use lithium salts such as lithium orotate ^[25] or lithium aspartate ^[6]. Interest in low doses comes from drinking-water studies linking lithium with lower suicide and dementia rates ^{[9, 12]}, a small Alzheimer's trial of 0.3 mg a day ^[16], and a 2025 mouse study of lithium in Alzheimer's disease ^[29].

2. Forms and Bioavailability

Lithium supplements are available in several chemical forms, each with different elemental lithium content, absorption characteristics, and safety profiles.

Comparison Table

Lithium Orotate

Lithium orotate contains 3.83% lithium by weight: each 100 mg of the compound provides 3.83 mg of lithium (Pauze and Brooks, J Med Toxicol, 2007) ^[25].

Animal studies showing enhanced brain penetration: In a 1978 rat study, lithium orotate injected into the abdomen gave higher serum and brain lithium levels than the same dose of lithium carbonate. At 24 hours, brain lithium was about three times higher with the orotate (Kling et al., J Pharm Pharmacol, 1978) ^[4].

However, a 1979 study repeated the experiment and also measured kidney function. Rats given lithium orotate filtered blood and made urine far more slowly than rats given lithium carbonate, which could account for their higher lithium levels. The authors concluded: "It seems inadvisable to use lithium orotate for the treatment of patients" (Smith and Schou, J Pharm Pharmacol, 1979) ^[5]. Whether this happens in people, especially at supplement doses, is not known.

Lithium Aspartate

Lithium aspartate was used in a long COVID trial and its follow-up ^[6]. The trial gave 10 to 15 mg a day, and the follow-up 40 to 45 mg a day ^[6]. The study names these doses as lithium aspartate; the blood lithium levels it reports suggest they are likely amounts of elemental lithium ^[6].

Lithium Citrate

Lithium citrate is a prescription liquid ^[2]. In 18 healthy men, lithium citrate syrup was absorbed faster than lithium carbonate tablets, peak blood levels were only about 10% higher, and the two were bioequivalent in total absorption (Guelen et al., Biopharm Drug Dispos, 1992) ^[7].

Lithium Chloride: A Historical Cautionary Tale

Lithium chloride was used in the US in the late 1940s as a salt substitute, and toxic effects were reported in people who used it (Hanlon et al., JAMA, 1949) ^[8].

How to Read a Supplement Label

Supplement labeling for lithium can be confusing because of the difference between the lithium compound weight and the elemental lithium content:

• Prescription lithium doses are given as the weight of the compound, not of the lithium it contains ^[25].
• Supplement labels may give either the compound or the elemental lithium, so check which one a label states.
• Published research does not always say whether a dose means the compound or elemental lithium; the long COVID trial is one example ^[6].

Compare products by their elemental lithium content, not the weight of the lithium compound.

In Vitro and Mechanistic Comparisons

In the 2025 Nature mouse study, the researchers used lithium orotate because it binds less to amyloid than other lithium salts (Aron et al., Nature, 2025) ^[29]. No study has compared the supplement forms in people.

3. Evidence for Benefits

Mood, Suicide, and Mental Health

Lithium in Drinking Water and Suicide Risk

Some evidence for low-dose lithium comes from ecological studies examining the relationship between naturally occurring lithium in drinking water and population-level mental health outcomes.

Early ecological studies: A study of 27 Texas counties found that rates of suicide, homicide, and rape were significantly higher in counties whose water contained little or no lithium than in counties with 70 to 170 micrograms of lithium per liter (Schrauzer et al., Biol Trace Elem Res, 1990) ^[9]. A study of 40 municipalities in Aomori, Japan, found a statistical trend toward a link between tap-water lithium and suicide mortality among females (Sugawara et al., Int J Environ Res Pub Health, 2013) ^[10].

US groundwater study: A 2018 US study examined groundwater lithium and diagnoses of bipolar disorder and dementia while adjusting for local health care resources and demographics (Parker et al., JAMA Psychiatry, 2018) ^[11].

Danish dementia study: A Danish nationwide study compared long-term drinking-water lithium between people diagnosed with dementia and matched controls. Compared with 2.0 to 5.0 µg/L, more than 15.0 µg/L was associated with a lower rate of dementia (IRR 0.83, 95% CI 0.81 to 0.85), but 5.1 to 10.0 µg/L was associated with a higher rate (IRR 1.22, 95% CI 1.19 to 1.25) (Kessing et al., JAMA Psychiatry, 2017) ^[12]. Such data cannot show cause and effect: the authors note that confounding by other factors linked to where people live cannot be excluded ^[12].

Low-Dose Lithium for Depression and Mood

One psychiatrist has written in favour of very low-dose lithium orotate for mood problems, based on his clinical experience rather than trials (Greenblatt and Grossmann, Townsend Letter, 2015) ^[13].

In a small placebo-controlled trial, 24 former drug users took tablets of a naturally lithium-rich brewer's yeast providing 400 micrograms of lithium a day for 4 weeks; mood scores, including happiness, rose in the lithium group, which suggests this very low dose may improve mood (Schrauzer and de Vroey, Biol Trace Elem Res, 1994) ^[14].

Alcoholism and Addiction

A 1986 report by Sartori described 42 alcoholic patients who took 150 mg/day of lithium orotate during rehabilitation. They were the 42 of 105 starters who stayed on treatment for at least six months, drawn from one private practice's records. Ten had no relapse for over three and up to 10 years, 13 had none for 1 to 3 years, and 12 relapsed within 6 to 12 months. Side effects were minor: eight patients had muscle weakness, loss of appetite or mild apathy ^[15]. It was a case series with no control group, not a randomised trial ^[15].

Cognitive Impairment, Alzheimer's Disease, and Dementia

Trials of lithium in mild cognitive impairment and Alzheimer's disease have given mixed results ^{[16, 17, 19, 21]}.

Alzheimer's Disease

Low-dose clinical trial (positive): A 15-month trial gave people with Alzheimer's disease a microdose of 300 micrograms (0.3 mg) of lithium once a day. Unlike the control group, the treated group's Mini-Mental State Examination scores did not fall; the difference became significant three months after treatment began and grew over time (Nunes et al., Curr Alzheimer Res, 2013) ^[16].

Higher-dose clinical trial (negative): An earlier 10-week trial randomly assigned 71 people with mild Alzheimer's disease to placebo or lithium, with a 6-week titration to a blood lithium level of 0.5 to 0.8 mmol/L. Lithium did not change overall cognitive performance or depressive symptoms (Hampel et al., J Clin Psychiatry, 2009) ^[17].

In a subset of the trial's participants, lithium significantly raised serum brain-derived neurotrophic factor (BDNF) and improved scores on a cognitive impairment scale compared with placebo (Leyhe et al., J Alzheimers Dis, 2009) ^[18].

Preclinical data: A 2025 study in Nature suggests that lithium orotate may help prevent Alzheimer's-type changes: in mouse models it prevented amyloid and tau changes and memory loss (Aron et al., Nature, 2025) ^[29]. This research is still at an early stage, and mouse findings may not hold in people. Brad's video on the mouse study adds that the same research found much lower lithium in the brains of people with mild cognitive impairment or Alzheimer's disease, and that in mice lithium orotate almost completely blocked plaque and tau build-up while lithium carbonate had no significant effect; the findings rest mainly on mouse models ^[28].

Epidemiological evidence: The Danish drinking-water study described above linked the highest water lithium levels with a lower dementia rate ^[12].

Mild Cognitive Impairment

Positive trial (moderate-dose lithium): A placebo-controlled trial in Brazil randomised 45 older people with amnestic mild cognitive impairment to lithium (blood level 0.25 to 0.5 mmol/L) or placebo for 12 months; lithium was associated with lower levels of P-tau, a marker of Alzheimer's disease, and better scores on some cognitive tests (Forlenza et al., Br J Psychiatry, 2011) ^[19]. Its dose ranged from 150 to 600 mg lithium carbonate (about 28 to 113 mg elemental lithium), a prescription-level amount ^{[16, 25]}. An extended follow-up found more of certain adverse effects with lithium (Aprahamian et al., J Clin Psychiatry, 2014) ^[20]; see the Safety section.

Negative trial (lower-dose lithium): A pilot trial gave daily low-dose lithium carbonate or placebo for 2 years to 80 adults aged 60 or older with mild cognitive impairment. None of its six main outcomes, which covered memory, brain volume and BDNF, met the prespecified significance threshold (Gildengers et al., JAMA Neurol, 2026) ^[21]. Verbal memory fell a little more slowly with lithium (0.73 versus 1.42 points a year); this reached nominal significance (P = .05) but not the prespecified threshold of P < .01 ^[21]. Participants who completed the trial took a mean of 195 mg of lithium carbonate a day, with a mean blood lithium of 0.17 mEq/L ^[21].

Synthesis on cognitive impairment: Of these trials, only the small Nunes study used a dose in the supplement range, 0.3 mg a day ^[16].

Brain-Derived Neurotrophic Factor (BDNF) and Neuroprotection

BDNF supports nerve cells, and studies have found lower BDNF levels in the blood and brain in Alzheimer's disease ^[18]. In rat cortical neurons, lithium raised BDNF content within 3 days, and its protection against glutamate toxicity depended on BDNF and its receptor TrkB (Hashimoto et al., Neuropharmacology, 2002) ^[22].

In a subset of the Hampel trial's participants, lithium raised blood BDNF levels ^[18].

Long COVID

A small randomised trial in 52 adults with long COVID fatigue or brain fog found that lithium aspartate, 10 to 15 mg a day for 3 weeks (likely elemental lithium, judging by the blood levels the study reports), was no better than placebo for fatigue or cognitive symptoms ^[6].

In an open-label follow-up, among 3 people who completed it, 40 to 45 mg a day of lithium aspartate was associated with numerically greater reductions in fatigue and cognitive dysfunction scores than 15 mg a day, particularly in 2 people with blood lithium levels of 0.18 and 0.49 mEq/L (Guttuso Jr. et al., JAMA Netw Open, 2024) ^[6].

The authors say another randomised trial is needed to test higher doses ^[6].

Longevity and Anti-Aging

Epidemiological Associations with Longevity

No study in this article measured human lifespan. A review by Schrauzer cites studies from the 1970s to the 1990s in which rats and goats fed low-lithium diets had higher death rates and reproductive and behavioral problems; no lithium deficiency disease has been defined in humans ^[23]. The drinking-water studies link lithium with suicide and dementia rates, but confounding by other factors linked to where people live cannot be excluded ^[12].

Migraine Prophylaxis

The sources for this article include no controlled trial of low-dose lithium for migraine.

4. Recommended Dosing

No Established Effective Dose

No effective dose of low-dose lithium has been established: the trials above used very different amounts, from 0.3 mg a day to prescription doses ^{[16, 19]}. The doses below are those used in research and clinical practice, not proven therapeutic thresholds.

Dosing Summary by Context

Practical Dosing Considerations

Starting dose: The best dose is not known. One researcher has proposed a provisional intake of 1 mg a day for adults ^[23].

Elemental lithium vs. compound weight: Check the label for elemental lithium. A tablet listed as 120 mg of lithium orotate provides only a few milligrams of lithium ^[25].

Hydration: Dehydration makes lithium toxicity more likely, so drink enough fluids while taking lithium, especially at higher doses ^[27].

Timing: No timing advice has been established for low-dose lithium.

5. Safety and Side Effects

Lithium Orotate Supplement Overdose

Any lithium salt can cause toxicity in overdose: an 18-year-old developed mild lithium toxicity after taking 18 tablets of a lithium orotate supplement (Pauze and Brooks, J Med Toxicol, 2007) ^[25]. The authors add that chronic toxicity from such products is a theoretical concern ^[25].

Short-Term Lithium Aspartate (Long COVID Trial)

In the 3-week long COVID trial, lithium aspartate at 10 to 15 mg a day caused no adverse events attributed to lithium ^[6]. Longer-term safety at these doses is not known.

Low-Dose Lithium Carbonate in Older Adults (2-Year Trial)

In the 2-year Gildengers trial of low-dose lithium carbonate in older adults (mean dose 195 mg a day), these side effects were more common with lithium than with placebo ^[21]:

The authors noted that older adults had substantial difficulty tolerating more than 300 mg a day ^[21]. With long-term use, lithium can also cause weight gain ^{[3, 20]}, an underactive thyroid and raised blood calcium ^[27].

Low-Dose Lithium Over 4 Years in Older Adults

A 4-year trial in older adults with mild cognitive impairment (2 years placebo-controlled, then 2 years single-blind) found no change in kidney function with low-dose lithium. However, the lithium group had ^[20]:

• More diabetes (P = .037) and arrhythmia (P = .028)
• Higher TSH, body weight and neutrophil counts
• More adverse events overall, especially ones that interfered with daily activities

Thyroid Effects

Lithium collects in the thyroid and can reduce thyroid hormone production, leading to an underactive thyroid (hypothyroidism) ^[27]. Environmental exposure may matter too: in 202 women in four Andean villages in Argentina, where drinking water is high in lithium, higher urine lithium was linked with lower thyroxine and higher TSH (Broberg et al., Environ Health Perspect, 2011) ^[24]. The Aprahamian trial also found higher TSH with lithium ^[20].

Kidney Effects

Long-term prescription lithium is linked with chronic kidney disease, and the label advises checking kidney function before and during treatment ^[27]. Most lithium-related kidney effects are relatively mild, but a small percentage of people treated with lithium develop progressive kidney impairment ^[3]. The Aprahamian 4-year trial of low-dose lithium found no change in kidney function ^[20].

Whether the kidney effects of lithium orotate seen in the 1979 rat study ^[5] happen in people, especially at supplement doses, is not known.

General Toxicity

Mild signs of lithium toxicity include a fine tremor, lightheadedness, poor coordination and weakness; moderate signs include drowsiness, unsteadiness, blurred vision, ringing in the ears and slurred speech ^[27]. Toxicity can also cause nausea, vomiting and diarrhea, and severe toxicity can cause confusion, seizures, coma and death ^[27]. If you take lithium and develop confusion, severe vomiting or diarrhea, marked unsteadiness or a seizure ^[27], get urgent medical help: call your local emergency number (111 in NZ, 000 in Australia, 911 in the US, 999 in the UK) or go to the emergency department.

Risk Factors for Lithium Accumulation

Some factors can push blood lithium up ^[27]:

• Dehydration: makes toxicity more likely ^[27]
• NSAIDs: slow the kidneys' clearance of lithium ^{[27, 33]}
• Diuretics, ACE inhibitors and ARBs: can raise blood lithium ^[27]
• Fever, prolonged sweating or diarrhea: fever raises the risk of toxicity, and prolonged sweating or diarrhea lower tolerance to lithium ^[27]
• A low-salt diet: the label advises a normal diet, including salt, and enough fluids ^[27]
• A new GLP-1 agonist, or a switch to another one, in someone already stable on lithium ^{[31, 32]}

These effects are documented in people taking prescription lithium ^{[27, 31]}; whether they occur with low-dose supplements is not known.

Contraindications

The prescription label says lithium should not be used in severe kidney impairment, and people with milder kidney impairment need lower doses and close monitoring ^[27]. Talk to your doctor before taking lithium if you are pregnant, have kidney or thyroid problems, or take other medicines. If you take any form of lithium, tell your doctor before you start or change a GLP-1 agonist, or start or raise an NSAID (see Drug Interactions). The label also says lithium should be avoided in people who have, or may have, Brugada syndrome, a heart disorder seen on an ECG (heart tracing) that carries a risk of sudden death ^[27].

Special Populations

• Older adults: The lithium trials in older adults described above found more side effects with lithium than with placebo ^{[20, 21]}.
• People taking prescription lithium: Toxic blood levels are close to the treatment range ^[27], so do not add a lithium supplement without your doctor's advice.
• Pregnancy: The prescription lithium label warns that lithium may cause harm when taken in pregnancy. Early reports linked first-trimester use with heart malformations, especially Ebstein's anomaly; later studies suggest the added risk is likely small, but the data are insufficient to establish it ^[27]. Talk to your doctor before taking any form of lithium if you are pregnant.
• Breastfeeding: Lithium passes into breast milk, and the prescription label says breastfeeding is not recommended while taking lithium ^[27].

6. Drug Interactions

The interaction evidence for lithium comes from people taking high-dose prescription lithium ^{[27, 31, 32, 33]}.

Drugs That Increase Lithium Levels (Risk of Toxicity)

In one case report, a woman on long-term prescription lithium developed severe lithium toxicity after raising both her lithium dose and her dose of the NSAID nabumetone (Hower et al., Cureus, 2026) ^[33]. The prescription lithium label adds that NSAIDs decrease blood flow to the kidneys, which lowers lithium clearance and raises blood lithium ^[27].

Other Notable Interactions

• Serotonergic drugs: Taking lithium with SSRIs, SNRIs, triptans, tricyclic antidepressants, tramadol, St John's wort or other serotonergic drugs can trigger serotonin syndrome, a potentially life-threatening condition; the label advises watching for its signs, especially when lithium is started ^[27].
• Switching GLP-1 agonists: In one case report, a man on stable lithium developed toxicity after switching from semaglutide to tirzepatide, which suggests that switching GLP-1 agonists may also make toxicity more likely (Burson and Leung, Ment Health Clin, 2026) ^[32].

Practical Guidance

It is not known whether these interactions happen at supplement doses. The case-report authors advise closer monitoring of lithium levels when a GLP-1 agonist is started, changed or switched, and after other medicine changes ^{[31, 32, 33]}. If you take any form of lithium, tell your doctor before you start or change a GLP-1 agonist, or start or raise an NSAID.

This list is not complete. The prescription lithium label names other interacting medicines too ^[27]. Check with your doctor or pharmacist before combining any form of lithium with another medicine.

7. Dietary Sources

Lithium is found in variable amounts in foods, and in some areas drinking water also provides significant amounts. Intake depends on location and the type of food eaten, and varies over a wide range ^[23].

Lithium in Drinking Water

Drinking-water lithium varies widely:

• Denmark: 2.0 to 5.0 µg/L in the lowest-exposure group and more than 15.0 µg/L in the highest ^[12]
• Texas: 70 to 170 micrograms per liter in some counties ^[9]
• Argentine Andes: high lithium levels have been found in drinking water in some villages ^[24]

Across the United States, lithium in public-supply groundwater wells ranged from less than 1 to 396 micrograms per liter, with a median of 8.1 (Lindsey et al., Sci Total Environ, 2021) ^[26].

Lithium in Food

The primary food sources of lithium are grains and vegetables ^[23].

Lithium-Rich Brewer's Yeast

Naturally lithium-rich brewer's yeast has been used in research: the Schrauzer mood study gave tablets providing 400 micrograms of lithium a day ^[14].

Variability and Uncertainty

A 2002 review by Schrauzer argued that the evidence was sufficient to accept lithium as essential and suggested a provisional intake of 1,000 micrograms a day for a 70 kg adult; this remains a researcher's suggestion ^[23].

Regulatory Status

Lithium is not permitted in supplements in the UK or EU, and is restricted in Australia and Canada (Brad's current guidance, 9 Oct 2026).