What is Lithium?
Lithium is a mineral naturally found in many of the foods we eat, and one that carries out a wide range of functions in our bodies, particularly our brains. Many studies have demonstrated the protective and growth-promoting effects Lithium has on the brain, not just for people with psychiatric and neurodegenerative diseases, but for healthy people too. Unfortunately, overcropping and water filtration means the amount of Lithium we obtain from food has declined massively over the past century, which has led some medical professionals to recommend supplementing it.
What forms is Lithium available in?
Lithium Citrate was the first salt to be used as a medication in humans, but it has been largely overtaken by Lithium Carbonate. Lithium Orotate and Lithium Aspartate have come to the table more recently, and are primarily sold as over-the-counter supplements. Other forms of Lithium are rare.
While the Lithium contained in all these supplements and medications is the exact same mineral, the salt or chelate to which it is bound may lead to differences in absorption, efficacy, and safety. In addition, each salt has a different molecular weight, meaning the percentage of actual Lithium varies. For example, Lithium Carbonate contains 18.7% Lithium while Lithium Orotate contains only 3.83%.
How are different forms of Lithium absorbed?
According to a review of the role of Lithium as a nutrient, both Lithium Aspartate and Lithium Orotate are very stable, and are thought to be absorbed from the intestine and transported to the body’s cells mostly intact. In contrast, Lithium Carbonate and Lithium Citrate Ionise (break apart) readily to produce Lithium ions, which are thought to be less efficient at diffusing into the cell. While this hasn’t been proven for Lithium salts specifically, it is known that absorption of iron, zinc, magnesium, calcium, manganese, and copper is better when they are ingested as amino acid chelates than when they are ingested as inorganic salts. A 1992 report on monitoring Lithium therapystates that absorption differs between different forms of Lithium, but does not cite any evidence.
In opposition to this view is a 1976 study that found no significant difference in the pharmacokinetics of Lithium Orotate, Carbonate, and Citrate based on measurements of Lithium concentrations in serum and body tissues after administration by either injection or ingestion. However, these results are not directly applicable in a clinical situation, because Smith administered amounts well in excess of recommendations for Lithium Orotate. It is possible that similar tissue levels may also be achieved with a lower dose of Lithium Orotate.
As it stands, we just don’t know for sure whether there is a difference in the way the body absorbs and utilises Lithium Orotate and Aspartate compared with Lithium Carbonate and Citrate. However, if it is true that Lithium Orotate delivers Lithium to cells more effectively, this means we can use much lower doses to get the same effect. Again, while this hasn’t been proven, many anecdotal reports certainly suggest therapeutic effects at low doses.
Are some forms of Lithium safer than others?
Neither Lithium Orotate nor Lithium Aspartate is approved by the US FDA, and no systematic reviews exist to definitively prove its safety or efficacy. However, anecdotal evidence abounds. Lithium Orotate has been used as a supplement for decades now, and no serious side effects or deaths have ever been reported.
While studies are lacking to investigate the effects of Lithium Orotate or Aspartate specifically, we know that Lithium in small amounts is safe, because it occurs naturally in soil and therefore in many of the foods we eat. But as we know from extensive studies on the use of Lithium Carbonate in a medical setting, side effects do start to appear at higher doses. (Actually, the serum levels of Lithium Carbonate required to achieve therapeutic effects border on toxic.)
Concerns have been raised about the safety of the Orotate component, despite the fact that it occurs naturally in living organisms. Aspartate, too, is consumed naturally in the foods we eat. In fact, the human body actually synthesises both Orotate and Aspartate. However, Aspartate is known to stimulate certain receptors in the brain, and it is to be expected that beyond a certain level it may have a toxic effect. It seems reasonable to assume that any potential toxicity from Orotate must also be dose-related.
A 1979 study found an association between Lithium Orotate administration and reduced kidney function, leading the authors to conclude that Lithium Orotate should be considered unsafe. However, the doses used in this study were an order of magnitude higher than the recommended doses and are therefore not clinically applicable.
Overall, just as we don’t know for sure about the bioavailability of Lithium Orotate, we don’t know for sure about its safety. On the other hand, we know for sure that Lithium Carbonate is associated with reduction in long-term renal function. A 2015 studytracked serum creatinine levels (an indicator of renal compromise) in nearly 5000 patients and found that about one-third of the patients who had taken Lithium for 10-29 years had evidence of chronic renal failure.
For more on the safety of Lithium Orotate, see ‘Is Lithium Orotate safe?’
Do all forms of Lithium cause side effects?
All forms of Lithium can cause side effects if the dose is high enough. But the biggest difference between the different forms of Lithium is exactly that: the size of the dose.
Lithium Carbonate has been associated with many side effects, including increased thirst and urination, dry mouth, hand tremors, confusion, impaired memory, headaches, and muscle weakness.
On the other hand, side effects of Lithium Orotate have only rarely been reported. In one study, some patients developed mild apathy, inappetence, and weakness at a daily dose of 150 mg (25% higher than the standard dose in most commercial preparations), and the author of the study reported that these side effects disappeared when the dosage was reduced from daily to only 4 or 5 times weekly. One case study reported nausea, emesis, and mild tremors in a woman who consumed 18 times the recommended dose of Lithium Orotate.
For more on the side effects of Lithium Carbonate and Lithium Orotate, see ‘Is Lithium Orotate safe?’