Provided herein is a method of using threonate to alter cellular physiology, such as neuronal physiology. A method of the present disclosure may include providing to a medium comprising a cell, a threonate-containing compound, or a precursor thereof, to increase the concentration of threonate in the medium, where the increased concentration of threonate is sufficient to increase the concentration of magnesium in the cell. Also provided is a method that includes administering a threonate-containing compound, or a precursor thereof, to an individual, to increase synaptic density in the brain and/or to treat a neurological disorder, e.g., cognitive impairment. The threonate-containing compound of the present disclosure does not include magnesium threonate.