Lithium-containing dietary supplements in the United States: an analysis of label-reported doses and claims

Abstract

Lithium is a mainstay treatment in bipolar disorder and is used in various psychiatric conditions. Micro or trace doses have also been suggested to have potential neuropsychiatric effects. Dietary supplements containing lithium are available in the US, but no studies have evaluated their labelling regarding dosing, health claims, or precautionary practices. Products from the Dietary Supplement Label Database (DSLD) marketed between 2011 and 2025 were reviewed, with composition and dosing derived from declared labelling. Lithium amounts, mood-, cognitive-, and suicide-related claims, and precautions for pregnancy/breastfeeding, kidney, and antidepressant use were assessed, and associations with dosing were analysed using Mann–Whitney U tests with correction for multiple comparisons. Of 439 products, 99 met inclusion criteria. Forty-one percent were lithium-only, with reported elemental lithium ranging from trace amounts to 25 mg (median, 1.5 mg). Some elemental lithium amounts were comparable to the lowest manufactured doses of lithium carbonate. Lithium-only products contained higher elemental lithium than combination products ( p < 0.05), and lithium orotate was the predominant salt (52.5%). Products with mood-related claims had higher reported elemental lithium than those without (5 vs. 1 mg; p < 0.05), whereas no association was observed for cognitive claims. No products made suicide-related claims. Kidney- and antidepressant-related precautions were not associated with elemental lithium amounts, while products with pregnancy/breastfeeding precautions had higher reported content than those without (3.25 vs. 0.5 mg; p < 0.05). These findings highlight variability in dosing and labelling, with certain labelling features correlated with declared lithium amounts, possibly reflecting conventions in lithium use.