The study was performed in mice, so it cannot be certain that the results would translate equally to humans, but the findings are certainly worth looking at. Mice fed a choline-deficient diet showed altered microtubule function and postsynaptic membrane regulation as well as impaired motor function and glucose metabolism, plus elevated concentrations of soluble and insoluble beta-amyloid proteins and greater tau hyperphosphorylation at various locations in the hippocampus. Compared to normal control mice, transgenic mice (used as a model for Alzheimer’s disease [AD]) showed more severe impairments and higher levels of pathological markers.
It is increasingly recognized that the buildup of amyloid may be a consequence, rather than a cause, of AD, and that amyloid may be produced as a protective response to neuronal injury. Focus has been shifting away from amyloid as a causal factor in AD and toward insulin resistance and reduced brain glucose metabolism as driving factors of the observed memory loss, personality changes and other signatures of the condition. If choline deficiency adversely impacts glucose metabolism and insulin signaling, this could be one of multiple potential mechanisms by which an inadequate pool of this critical nutrient may be playing a role in disease pathology.
While the human body synthesizes choline endogenously (mainly in the liver), this is not sufficient to meet metabolic needs, so choline is considered an essential nutrient. It’s estimated, however, that as much as ninety percent of adults in the US fail to meet the adequate intake (425 mg for women; 550 mg for men). Risk for deficiency may be higher in those following vegetarian or plant-based diets, as the richest dietary sources of choline include eggs, liver, beef, and certain types of fish and shellfish. Select plant foods (such as Brussels sprouts, broccoli, cauliflower, and peanuts) also provide choline, but in lower amounts than animal sources.
The senior study author noted, “Our work provides further support that dietary choline should be consumed on a daily basis given the need throughout the body.” And the paper’s conclusion stated, “Our data highlight that dietary choline intake is necessary to prevent systems-wide organ pathology and reduce hallmark AD pathologies.”