Magnesium threonate combines elemental magnesium with threonic acid. Threonic acid helps transport magnesium across the protective blood-brain barrier where it can be used directly by neurons in the brain. Improving magnesium status in the brain has been shown to have a positive impact on nerve cell health, can improve synaptic density, and slows the natural biological aging of the brain. Dietary supplements are food products intended to supplement the normal diet, consisting of concentrated sources of nutrients or other substances that have a nutritional or physiological effect, in single or combined form, and are marketed in such a way as to allow a specific dosage of each product and to be taken in small unit quantities.