Phosphatidyl choline is the predominant building block of plant and animal cell membranes. Adequate levels of phosphatidyl choline are necessary for cellular function, communication, and transport. Phosphatidyl choline is also critical for many aspects of physiology from neurotransmitter production to fat and cholesterol metabolism.
Phosphatidyl choline (PC) is the predominant building block of animal and plant cell membranes. It is required for the integrity of the phospholipid bilayers that contain the cell and the organelles within the cell. Although small amounts of choline, the primary and necessary nutrient derived from PC, can be synthesized from methionine or serine, it is considered an essential nutrient and must be obtained from the diet.[1] Although thresholds have been established for adequate intake of choline, studies have shown that this may not be sufficient for prevention of symptoms of choline deficiency such as fatty liver or muscle damage.[2] Higher amounts of PC can be found in foods such as egg yolks, liver, meats, broccoli, brussel sprouts, and milk.[3] Because higher amounts of choline are found in animal products, there is a risk of deficiency in individuals who are vegetarian or vegan. A higher risk of deficiency has also been observed at in men, postmenopausal women, and individuals with genetic polymorphisms related to folate or choline metabolism.2,[4] Supplemental intake of PC is one means of providing sufficient choline for the body’s needs.
| Although thresholds have been established for adequate intake of choline, studies have shown that this may not be sufficient for prevention of symptoms of choline deficiency such as fatty liver or muscle damage. |
Cellular and biochemical function. The phospholipid bilayers that form the external cellular membrane as well as that of the mitochondria, endoplasmic reticulum, Golgi apparatus all depend upon PC for their existence. It is critical for membrane integrity, structure, and function, and depletion has been shown to adversely affect the function of these organelles.[5],[6] Choline supports the body’s antioxidant status, reducing lipid peroxidation.[7] Deficiency of PC has been shown to lead to cellular damage via oxidative mechanisms in the liver, heart, kidneys, and brain. [8]
Sufficient levels of PC are necessary for many biochemical pathways, supporting critical functions and physiology. This includes fat and cholesterol metabolism, homocysteine metabolism, fetal development, neurocognitive health and development, and liver detoxification of chemicals, heavy metals, and xenobiotics. Choline provided by PC is a precursor for the synthesis of acetylcholine, an important neurotransmitter centrally in the brain, and necessary peripherally for muscle control and other aspects of cholinergic signalling.[9] PC is also a major source of methyl groups via its metabolite trimethylglycine (TMG), which is important for Phase II hepatic detoxification.
Clinical research surrounding phosphatidyl choline
Issues associated with metabolic syndrome. PC is a normal constituent of bile and facilitates fat emulsification, absorption, and transport. PC also is an integral part of the structure of circulating lipoproteins. Supplementation with lecithin, providing PC, has been shown to significantly reduce total cholesterol, low-density lipoprotein (LDL), and triglyceride levels while simultaneously increasing high-density lipoprotein (HDL) levels in individuals with hyperlipidemia.[10] In animal models, restoration of PC levels has been shown to be protective against hepatic steatosis and in part by supporting antioxidant status.[11]
Central nervous system effects. Lower plasma levels of PC have been observed in individuals with cognitive impairment, Alzheimer’s disease and other types of dementia.[12] Levels of acetylcholine, a neurotransmitter of significant interest particularly in settings of cognitive function, are supported by sources of choline such as PC. In an animal model, supplementation with PC have been shown to improve memory of mice with dementia as well as increase the brain acetylcholine concentration.[13] In a double-blind test with healthy college students utilizing a low and high dose of PC, higher doses of PC were shown to explicit memory, with greatest increases at 90 minutes after ingestion.[14] In a placebo-controlled double-blind study, supplementation of choline in the form of choline bitartrate improved performance on a speed-based visuomotor test as well as significantly decreased pupil size, a cognition-sensitive biomarker.[15] In a slightly different setting yet still related to the central nervous system, choline bitartrate was found to substantially reduce manic symptoms as well as improve symptoms of mood in patients taking lithium for the treatment of bipolar disorder.[16]
Gastrointestinal disorders. The intestinal mucus contains high amounts of PC, with PC comprising 90% of the phospholipids found in it.[17] PC is protective and supportive to the gastrointestinal mucosal barrier, and has been shown to exert an anti-inflammatory effect in colon cells.[18] An increased intake of foods high in phospholipids has been shown to be protective against gastric and duodenal ulcer formation and to promote ulcer healing.[19] In patients with ulcerative colitis (UC), the protective colonic mucus PC content has been shown to be reduced by 70% from that of a normal population regardless of the state of inflammation.17 The colon mucus barrier is critical to protecting the underlying tissue from irritation as well as infection, and the lower content of PC may be one factor that contributes to inflammation and immune activation in UC. Supplementation of PC to patients with UC has been shown to improve remission and reduce the need for corticosteroid treatment.[20]
Exercise performance and recovery. As intense exercise for an extended duration can lead to depletion of circulatory choline, PC has been studied for the potential impact it may have on sport performance.[21] Choline from PC is involved in the formation of acetylcholine, the neurotransmitter that is necessary for peripheral muscle contractions. Acute supplementation of PC prior to exercise has been shown to improve some aspects of athletic performance and markers of recovery such as decreased lactic acid concentrations and faster return to normal heart rate.
Author, Dr. Carrie Decker
Dr. Decker is a certified Naturopathic Doctor, graduating with honors from the National College of Natural Medicine (now the National University of Natural Medicine) in Portland, Oregon. Dr. Decker also has graduate degrees in biomedical and mechanical engineering from the University of Wisconsin-Madison and University of Illinois at Urbana-Champaign respectfully. Dr. Decker sees patients at her office in Portland, OR, as well as remotely, with a focus on gastrointestinal disease, mood imbalances, eating disorders, autoimmune disease, chronic fatigue, and skin conditions. Dr. Decker also supports integrative medicine education as a writer and a contributor to various resources.
[1] Canty DJ, Zeisel SH. Lecithin and choline in human health and disease. Nutr Rev. 1994 Oct;52(10):327-39. View Abstract
[2] Fischer LM, et al. Sex and menopausal status influence human dietary requirements for the nutrient choline. Am J Clin Nutr. 2007 May;85(5):1275-85. View Full Paper
[3] Linus Pauling Institute. Micronutrient Information Center. Choline. Accessed on March 7, 2017. View Website
[4] Zeisel SH. Gene response elements, genetic polymorphisms and epigenetics influence the human dietary requirement for choline. IUBMB Life. 2007 Jun;59(6):380-7. View Full Paper
[5] Spector AA, Yorek MA. Membrane lipid composition and cellular function. J Lipid Res. 1985 Sep;26(9):1015-35. View Full Paper
[6] Testerink N, et al. Depletion of phosphatidylcholine affects endoplasmic reticulum morphology and protein traffic at the Golgi complex. J Lipid Res. 2009 Nov;50(11):2182-92. View Full Paper
[7] Grattagliano I, et al. Starvation impairs antioxidant defense in fatty livers of rats fed a choline-deficient diet. J Nutr. 2000 Sep;130(9):2131-6. View Full Paper
[8] Repetto MG, et al. Oxidative damage: the biochemical mechanism of cellular injury and necrosis in choline deficiency. Exp Mol Pathol. 2010 Feb;88(1):143-9. View Abstract
[9] Löffelholz K, Klein J, Köppen A. Choline, a precursor of acetylcholine and phospholipids in the brain. Prog Brain Res. 1993;98:197-200. View Abstract
[10] Wojcicki J, et al. Clinical evaluation of lecithin as a lipid‐lowering agent. Phytother Res. 1995 Dec;9:597-9. View Abstract
[11] Kharbanda KK, et al. Betaine attenuates alcoholic steatosis by restoring phosphatidylcholine generation via the phosphatidylethanolamine methyltransferase pathway. J Hepatol. 2007 Feb;46(2):314-21. View Abstract
[12] Conquer JA, et al. Fatty acid analysis of blood plasma of patients with Alzheimer's disease, other types of dementia, and cognitive impairment. Lipids. 2000 Dec;35(12):1305-12. View Abstract
[13] Chung SY, et al. Administration of phosphatidylcholine increases brain acetylcholine concentration and improves memory in mice with dementia. J Nutr. 1995 Jun;125(6):1484-9. View Abstract
[14] Ladd SL, et al. Effect of phosphatidylcholine on explicit memory. Clin Neuropharmacol. 1993 Dec;16(6):540-9. View Abstract
[15] Naber M, Hommel B, Colzato LS. Improved human visuomotor performance and pupil constriction after choline supplementation in a placebo-controlled double-blind study. Sci Rep. 2015 Aug 14;5:13188. View Full Paper
[16] Stoll AL, et al. Choline in the treatment of rapid-cycling bipolar disorder: clinical and neurochemical findings in lithium-treated patients. Biol Psychiatry. 1996 Sep 1;40(5):382-8. View Abstract
[17] Stremmel W, et al. Mucosal protection by phosphatidylcholine. Dig Dis. 2012;30 Suppl 3:85-91. View Abstract
[18] Treede I, et al. Anti-inflammatory effects of phosphatidylcholine. J Biol Chem. 2007 Sep 14;282(37):27155-64. View Full Paper
[19] Tovey FI. Role of dietary phospholipids and phytosterols in protection against peptic ulceration as shown by experiments on rats. World J Gastroenterol. 2015 Feb 7;21(5):1377-84. View Full Paper
[20] Stremmel W, et al. Delayed release phosphatidylcholine as new therapeutic drug for ulcerative colitis--a review of three clinical trials. Expert Opin Investig Drugs. 2010 Dec;19(12):1623-30. View Abstract
[21] Jäger R, Purpura M, Kingsley M. Phospholipids and sports performance. J Int Soc Sports Nutr. 2007 Jul 25;4:5. View Full Paper
