Lithium‐Rich Mineral Water is a Highly Bioavailable Lithium Source for Human Consumption

Scope Lithium is an important trace element in human nutrition and medicine. Mineral and medicinal waters may represent a significant source of dietary lithium intake. Methods and results The lithium concentration of 360 German mineral and 21 medicinal waters is determined. Based on a systematic screening, three different mineral waters exhibiting low (1.7 µg L−1), medium (171 µg L−1), and high lithium (1724 µg L−1) concentrations are chosen for an acute bioavailability study in male healthy volunteers. In Germany, a north‐east to south‐west gradient of analyzed lithium concentrations is observed in the 381 tested waters. The lithium concentration in the water is significantly correlated with its sodium (r = 0. 810), potassium (r = 0.716), and magnesium (r = 0.361), but not with its calcium concentration. In a randomized cross‐over trial, volunteers (n = 3×10 each) drink 1.5 L of the respective mineral waters, and lithium concentrations in serum and urine are monitored over 24 h. Consumption of the mineral waters with a medium and high lithium content results in a dose‐dependent response in serum lithium concentrations and total urinary lithium excretion. Conclusion Lithium‐rich mineral and medicinal waters may be an important and highly bioavailable lithium source for human consumption. Lithium concentrations of German mineral water are determined. Substantial geographical differences in lithium concentrations of the analyzed waters are observed. Three different mineral waters exhibiting low, medium, and high lithium concentrations are chosen for a bioavailability study in humans. There is a dose‐dependent response in serum lithium concentrations and total urinary lithium excretion after the consumption of the respective mineral waters.