Choline poses little risk of adverse effects from over-consumption.
Choline doses that are orders of magnitude greater than estimated intake from food have been associated with fishy body odor, sweating, salivation, hypotension, and hepatotoxicity in humans (LSRO/FASEB, 1975, 1981). Both animal and human data support the fact that there is a low degree of toxicity from choline (IOM, 1998). Large doses that have been administered through intravenous or intraperitoneal injection have caused some growth suppression (LSRO/FASEB, 1975), but such doses have not been attained through food intake or supplementation (Sahu et al, 1986).
Trimethylamine is a choline metabolite and may be formed in healthy humans (Zeisel et al, 1983). The result of trimethylamine excretion is a fishy body odor. High dose choline treatment of patients with tardive dyskinesia and cellebellar ataxia (choline chloride at 150 – 220 mg/kg body weight for 2 – 6 weeks) caused symptoms including vomiting, salivation, sweating, and gastrointestinal effects (Davis et al, 1975; Growden et al, 1977b; Lawrence et al, 1980).
Changes in heart rate have not been observed in healthy humans treated with choline. Oral administration of 10 g/day of choline chloride had a slight hypotensive effect in humans (Boyd et al, 1977).
Individuals with renal disease, liver disease, depression, Parkinson’s disease and trimethyaminuria (fishy odor syndrome) may have increased susceptibility to the adverse effects of choline (IOM, 1998).
Boyd WD, Graham-White J, Blackwood G, Glen I, McQueen J (1977) Clinical effects of choline in Alzheimer senile dementia. Lancet 2:711.
Davis KL, Berger PA, Hollister LE (1975) Choline for tardive dyskinesia. N Engl J Med 293:152.
Growden JH, Hirsch MJ, Wurtman RJ, Wiener W (1977) Oral choline administration to patients with tardive dyskinesia. N Engl J Med 297:524-527.
IOM-NAS (1998) Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline. http:/www.nap.edu.catalog/6015.html
Lawrence CM, Millac P, Stout GS, Ward JW (1980) The use of choline chloride in ataxic disorders. J Neurol Neurosurg Psychiatry 43:452-454.
LSRO/FASEB (1975) Evaluation of the Health Aspects of Choline Chloride and Choline Bitartrate as Food Ingredients. Report #PB-223 845/9. Washington DC: Department of Health, Education, and Welfare
LSRO/FASEB (1981)Effects of Consumption of Choline and Lecithin on Neurological and Cardiovascular Systems. Report #PB-82-133257. Bethesda, MD: LSRO/FASEB.
Sahu AP, Saxena AK, Singh KP, Shanker R (1986) Effects of chronic choline administration in rats. Indian J Exp Biol 24:91-96.
Zeisel SH, Wishnok JS, Blusztajn JK (1983) Formation of methylamines from ingested choline and lecithin. J Pharmacol Exp Ther 225:320-324.