definition
Choline:
» metabolism:
Phosphatidylcholine (lecithin), a primary dietary source of choline, is composed of a phosphate group, 2 fatty acids, and choline. The composition of essential fatty acids in phosphatidylcholine determines its value in promoting health. When phosphatidylcholine is ingested, most of it is broken down into choline, glycerol free fatty acids, and the phosphate group, rather than being incorporated intact into cellular membranes.
Although choline can be manufactured in humans from either methionine or serine, it has recently been designated an essential nutrient.
» function:
Choline is required for the proper metabolism of fats; it facilitates the movement of fats in and out of cells. Like Vitamin B12, 5-adenosylmethionine, and Folic Acid, choline acts in the human body as a methyl donor. As such, choline is essential for proper liver function due to its key role in the lipotropic effect, i.e., the export of fat from the liver. In the absence of adequate choline, fats become trapped in the liver, where they block metabolism. Stagnation of fat and bile eventually leads to the development of more serious liver disorders such as cirrhosis.
Choline is needed for cell membrane integrity because of the critical role it plays in the manufacture of primary components of cell membranes, such as phosphatidylcholine and sphingomyelin.
Choline is essential in the synthesis of acetylcholine. Choline supplementation increases the accumulation of acetylcholine which plays a crucial role in many brain processes, including memory. (Canty, DJ and Zeisel, SH. Nutr Reviews. 52;327-339, 1994)
Phosphatidylcholine increases the solubility of cholesterol and thereby decreases cholesterols ability to induce atherosclerosis.
Phosphatidylcholine aids in lowering cholesterol levels, removing cholesterol from tissue deposits, and inhibiting platelet aggregation. (Brook, JG, Linn, S, and Aviram, M. Biochem Med Metabol Biol. 35;31-39, 1986.) The high content of linoleic acid in phosphatidylcholine may be responsible for much of the benefit derived from supplementation.
» Chinese:
Nourishes Xue (Blood), extinguishes Wind, nourishes the Sinews, and moistens the Intestines (Wolfe, Honora Lee. Menopause: A Second Spring. p. 118. Blue Poppy Press: Boulder, CO, 1995.)
» requirements:
Choline has recently been designated as an essential nutrient.
RDA:
Infants and children: 125 to 375 mg qd
Women: 425 mg qd
Men: 500 mg qd
Pregnant women: 450 mg qd
Breast-feeding women: 500 mg qd
Average intake in the U.S.: Approximately 6 g per day as phosphatidylcholine
» food sources:
As free choline in vegetables (especially cauliflower and lettuce), whole grains, liver, and soy.
As lecithin (phosphatidylcholine) in grains, legumes, meat and egg yolks.
Lecithin, containing 10-20% phosphatidylcholine, is also found in small amounts in many processed foods, where it has been added to maintain texture consistency.
Food Sources of Choline:
Choline and Choline Phospholipid Content of Selected Foods, in Milligrams per Serving
Food Serving Choline Lecithin Total Choline
Apple 1 medium 0.39 29.87 4.62
Banana medium 2.85 3.26 3.52
Beef liver 3.5 oz 60.64 3362.55 532.28
Beef steak 3.5 oz. 0.78 466.12 68.75
Butter 1 tsp. 0.02 6.80 1.18
Cauliflower 1/2 cup 6.79 107.06 22.15
Corn oil 1 tbsp. 0.004 0.13 0.03
Coffee 6 oz. 18.59 2.05 19.29
Cucumber 1/2 cup 1.18 3.06 1.74
Egg 1 large 0.22 2009.80 282.32
Ginger ale 12 oz. 0.07 1.11 0.34
Grape juice 6 oz. 8.99 2.11 9.37
Human milk 1 cup 2.10 27.08 10.29
Iceberg lettuce 1 oz. 8.53 2.86 9.06
Infant formula 1 oz. 0.818 2.97 1.38
Lecithin supplement 1 tbsp., 7.5 g. NA 1725 250
(commercial, powdered)
Margarine 1 tsp. 0.02 1.74 0.26
Milk whole 1 cup 3.81 27.91 9.64
Orange 1oz. 13.24 107.35 27.91
Potato 1 5.95 25.97 9.75
Tomato 1v 5.50 4.94 6.58
Whole wheat bread 1 slice 2.52 6.57 3.43
(USDA: Composition of Foods. USDA handbook # 8. Washington DC, ARS, USDA, 1976-1986)
» deficiency:
True choline deficiency appears to be rare or non-existent and has only been induced in a research setting.
Deficiencies typically present as muscle weakness, tingling in the fingers and toes, weight loss or fatigue.
Liver and kidney disorders develop when animals are fed a choline-deficient diet.
Fatty infiltration of the liver and other signs of liver dysfunction develops in humans fed a choline-deficient diet.
Choline is an essential nutrient for human cells in cell cultures, and humans receiving intravenous feeding with solutions low in choline develop signs of choline deficiency.
(Canty, DJ and Zeisel, SH. Nutr Reviews. 52;327-339, 1994; Zeisel, SH, et al. FASEB J 5;2093-2098, 1991)
» mode of action:
Choline acts as a methyl donor, especially in liver function.
Choline enables synthesis of acetylcholine, phosphatidylcholine and sphingomyelin.
» therapeutics:
Liver Disorders: Phosphatidylcholine is used in the treatment of a variety of liver disorders, including:
Acute viral hepatitis
Alcohol-induced fatty liver
Chronic hepatitis
Cirrhosis of the liver
Decreased bile solubility
Diabetic fatty liver
Drug-induced liver damage
Toxic liver damage
Alcohol-induced liver disease: Studies with baboons have found that phosphatidylcholine supplementation protects against alcohol-induced liver abnormalities and cirrhosis; presumably some of these same effects will be present in humans. Nevertheless, choline salts do not seem to be of any value in the treatment of alcohol-induced liver disease in humans but may be useful in general liver support. (Lieber,CS and Rubin, E. N Engl J Med 280;705-708, 1969.)
Hypercholesterolemia and atherosclerosis: Phosphatidylcholine increases the solubility of cholesterol and thereby decreases its ability to induce atherosclerosis. Phosphatidylcholine also aids in lowering cholesterol levels, removing cholesterol from tissue deposits, and inhibiting platelet aggregation. (Brook, JG, Linn, S, and Aviram, M. Biochem Med Metabol Biol. 35;31-39, 1986.) Here some of the beneficial effects may be attributable to the high content of linoleic acid in phosphatidylcholine.
The phospholipid preparation Lipostabil has been researched for use in the treatment of high cholesterol levels and atherosclerosis. In several trials evaluating this 70% phosphatidylcholine content lecithin product from Germany, total serum cholesterol and triglyceride levels dropped significantly and HDL cholesterol levels improved using dosage ranging from 1.5 g per day to 3.5 g three times daily (Lipostabil. Natterman International GMBH,1990; Wojcicki, J, et al. Phytotherapy Res. 9;597-599, 1995)
A high-concentration phosphatidylcholine preparation, marketed in Germany under the tradename "Essentiale", has produced clinical results consistent enough to gain authorization from the BGA, the German equivalent of the FDA. This form contains 90% phosphatidylcholine, with 50% of the molecule having linoleic acid, the essential fatty acid, bound at the proper position; i.e., the first and second carbon of the glycerol molecule. Using this preparation the standard dosage recommendation is 350 mg three times daily with meals. (Essentiale, Natterman International GMBH, 1989.)
Bipolar Depression: There is evidence that mania is associated with a reduced brain cholinergic activity. Phosphatidylcholine supplementation at levels of 15-30 g per day has been found to exert beneficial effects in the treatment of bipolar depression. (Wutman, R, et al. Nutrition and the Brain. Vol. 5. Raven Press: New York, 1979; Cohen, B, et al. Am J Psychiat 137:242-243, 1980; Cohen, B, et al. Am J Psychiat 139;1162-1164, 1982.)
The use of phosphatidylcholine may result in significant improvement or amelioration of symptoms in some patients suffering from bipolar depression by increasing brain choline levels. Some researchers believe that one effect of Lithium carbonate, the standard pharmaceutical treatment for bipolar depression, is the promotion of increased acetylcholine activity in the brain. (Jope, R, et al. Am J Psychiat 142;356-358,1985)
Alzheimers Disease: Choline supplementation increases the accumulation of acetylcholine within the brain in normal patients so many researchers hypothesized that phosphatidylcholine supplementation would benefit Alzheimer patients. Some research has indicated that increasing acetylcholine content in the brain through supplemental choline might result in improved memory. However, clinical trials using phosphatidylcholine have not produced significant benefits. Studies revealed inconsistent improvements in memory from choline supplementation in both normal and Alzheimers patients. Nevertheless, criticisms of these studies and their interpretations have been raised on the grounds that sample size was too small, the dosage of phosphatidylcholine used was too low, and the studies themselves were poorly designed. (Rosenberg, G and Davis, KL. Am J Clin Nutr. 36; 709-720, 1982; Levy, R, et al. Lancet 1;474-476,1982; Sitaram, N, et al. Life Sci 22;1555-1560, 1978.)
Alzheimers disease is characterized by a decrease in cholinergic transmission, but the basic defect in cholinergic transmission in Alzheimers disease relates to impaired activity of the enzyme acetylcholine transferase, not to a deficiency of choline. Acetylcholine transferase combines choline with an acetyl molecule to form acetylcholine. However, since increased levels of choline do not necessarily increase the activity of this critical enzyme, phosphatidylcholine supplementation will probably not prove efficacious in the majority of patients with Alzheimers disease.
In a patient with mild to moderate dementia, the use of a high-quality phosphatidylcholine preparation at a dosage level of 15 to 25 g per day may be beneficial. If there is no noticeable improvement within 2 weeks, supplementation should be halted. (Murray, M. p. 140, 1996.)
» dosage:
Using lecithin, the most common form of choline supplementation, with 90 percent phosphatidylcholine, the dosage (three times daily with meals) is:
350-500 mg three times daily for the treatment of liver disorders;
500-900 mg three times daily for lowering cholesterol;
5,000-10,000 mg per day for the treatment of Alzheimers disease and bipolar depression.
(Murray, M. p. 141, 1996)
» forms:
Choline is available as a soluble salt, most commonly as either choline bitartrate, citrate, or chloride, or as phosphatidylcholine in lecithin.
Most commercial forms of lecithin contains only 10-20% phosphatidylcholine.
Most supplements labeled as "phosphatidylcholine" contain only 35 percent.
Some newer and more potent preparations contains up to 98 percent phosphatidylcholine.
The more pure forms of phosphatidylcholine are preferred since they are associated with fewer gastrointestinal side effects. This is particularly true in the treatment of those conditions which require large doses of phosphatidylcholine (i.e., 15 to 30 grams) because low-concentration forms such as lecithin would be required in such large amounts that side effects would be nearly inevitable.
» side effects:
Choline and phosphatidylcholine are generally well tolerated.
At doses over 20g qd, pure choline, but not phosphatidylcholine, will produce a "fishy" odor.
High doses of lecithin, several grams per day, will produce reduced appetite, nausea, abdominal bloating, gastrointestinal pain and/or diarrhea in some people.
» toxicity:
No toxicity beyond the side effects mentioned above were found in any of the sources cited.
» contraindications:
Phosphatidylcholine is not indicated in patients with depression (unipolar or clinical depression) unless under the supervision of a physician because high-dosage phosphatidylcholine supplementation can worsen depression in some cases.
» interactions:
Choline works together with other methyl donors and helps the body conserve carnitine and folic acid. (Daily, JW and Sachan, DS. J Nutr 125;1938-1944, 1995; Varela-Mreiras, G, et al. J Nutr Biochem 3;519-522, 1992.)
Phosphatidylcholine and pantothenic acid are used to form acetylcholine.
footnotes
Brook, JG, Linn, S, and Aviram, M. Dietary soya lecithin decreases plasma triglyceride levels and inhibits collagen- and ADP-induced platelet aggregation. Biochem Med Metabol Biol. 35;31-39, 1986.
Canty, DJ, and Zeisel SH. Lecithin and choline in human health and disease. Nutr Reviews. 52;327-339, 1994.
Cohen, B, Miller, A, Lipinski, J, and Pope, H. Lecithin in mania: A preliminary report. Am J Psychiat 137:242-243, 1980.
Cohen, B, Lipinski, J, and Altesman, R. Lecithin in the treatment of mania: Double-blind, placebo controlled trials. Am J Psychiat 139;1162-1164, 1982.
Daily, JW and Sachan, DS. Choline supplementation alters carnitine homeostasis in humans and guinea pigs. J Nutr 125;1938-1944, 1995.
Essentiale, Essentiale forte. Natterman International GMBH, P.O. Box 350120, Cologne 5000, Germany, 1989.
Jope, R, Tolbert, L, Wright, S and Walter-Ryan, W. Biochemical RBC abnormalities in drug-free and lithium-treated manic patients. Am J Psychiat 142;356-358,1985.
Levy, R, Little, A, Chuaqui, P, and Reith, M. Early results from double-blind, placebo controlled trial of high dose phosphatidylcholine in Alzheimers Disease. Lancet 1;474-476,1982.
Lieber, CS, and Rubin, E. Alcoholic fatty liver. N Engl J Med 280, 705-708, 1969.
Lipostabil. Natterman International GMBH, P.O. Box 350120, Cologne 5000, Germany,1990.
Abstract: Studies were conducted in Germany using Lipostabil, a high-quality phospholipid preparation, for the treatment of high cholesterol levels and atherosclerosis. In 15 clinical trials ranging in length from 1-12 months, treatment with phosphatidylcholine lowered total serum cholesterol by 8.8% to 28.2% and triglyceride levels by an average of 25%; HDL cholesterol levels also increased by 13.4-20%. The typical dosage used was 1.5 to 2.7 g per day
Murray, M. Encyclopedia of Nutritional Supplements. p. 141. Prima Publishing: Rocklin, CA, 1996.
Rosenberg, G and Davis, KL. The use of cholinergic precursors in neuropsychiatric diseases. Am J Clin Nutr. 36; 709-720, 1982.
Sitaram, N, Weingartner, B, Gaine, ED, and Cillin, JC. Choline: Selective enhancement of serial learning and encoding of low imagery words in man. Life Sci 22, 1555-1560, 1978.
Varela-Mreias, G, et al. Effect of choline deficiency on liver folate content and distribution. J Nutr Biochem 3;519-522, 1992.)
Wojcicki, J, et al. Clinical evaluation of lecithin as a lipid-lowering agent. Phytotherapy Res. 9;597-599, 1995.
Abstract: In a recently published study evaluating a 70% phosphatidylcholine content lecithin product, marketed under the tradename Lipostabil, 32 patients with elevated cholesterol and triglyceride levels were given at a dosage of 3.5 g three times daily before meals. After 30 days of treatment, total cholesterol declined an average of 33%, triglycerides went down 33%, and HDL cholesterol levels increased by 46%.
Wolfe, Honora Lee. Menopause: A Second Spring. p. 118. Blue Poppy Press: Boulder, CO, 1995.
Wutman, R, Barbeau, A and Growdon, J. Choline and lecithin in brain disorders. Nutrition and the Brain. Vol. 5. Raven Press: New York, 1979.
Zeisel, SH, et al. Choline, an essential nutrient for humans. FASEB J5,2093-2098, 1991.