Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline (1998) / Chapter Skim
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12 Choline
12 Choline
Pages 390-422
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From page 390... ...
The critical adverse effect from high intake of choline is hypotension, with corroborative evidence on cholinergic side effects (e.g., sweating and diarrhea) and fishy body odor.
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From page 391... ...
Healthy men with normal folate and vitamin BY status feci a choline-cleficient cliet have climinisheci plasma choline and phosphaticlylcholine concentrations and develop liver damage (Zeisel et al., 1991~. For these inclivicluals, cle nova synthesis of choline was not acloquate to meet the clemanci for / , AdoHcy~ / ~ / DNA methylation other methylations Tetrahydrofolate methyl-THF _ Ado; PtdEtn Methionine .
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From page 392... ...
Betaine is also required by renal glomerular cells, which use betaine and glycerophosphocholine as organic osmolytes to adapt to osmotic stress (Bauernschmitt and Kinne, 1993; Burg, 1995; Garcia-Perez and Burg, 1991; Grossman and Hebert, 1989~. Physiology of Absorption, Metabolism, and Excretion Dietary choline is absorbed from the lumen of the small intestine via transporter proteins in the enterocyte (Herzberg and Lerner, 1973; Herzberg et al., 1971; Kuczler et al., 1977; Sheard and Zeisel, 1986~.
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From page 393... ...
A specific carrier mechanism transports free choline across the blooci-brain barrier at a rate that is proportional to the serum choline concentration. In the neonate this choline transporter has an especially high capacity (Cornforci and Cornforci, 1986~.
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From page 394... ...
Inclivicluals feci with total parenteral nutrition (TPN) solutions clevoici of choline but aclequate for methionine and folate develop fatty liver and liver damage as assessed by elevated alanine aminotransferase; in some incliviclu13 12 o 11 _' O)
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From page 395... ...
, four patients who haci low plasma concentrations of free choline after treatment with TPN (which contained no aciclitional choline) were given 1 to 4 g/day of choline chloride for 6 weeks.
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From page 396... ...
Phosphocholine concentration in liver is highly correlated with clietary choline intake, decreasing to 10 to 20 percent of control values after 2 weeks on a cliet sufficient in methionine, folate, and vitamin BE but deficient in choline (Pomfret et al., 1990~. Hepatic phosphocholine concentration was most sensitive to modest clietary choline deficiency, decreasing to 10 to 20 percent of control values after 2 weeks of a deficient cliet (Pomfret et al., 1990~.
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From page 397... ...
Plasma phosphaticlylcholine concentration also decreases in choline deficiency (Zeisel et al., 1991) but is also influenceci by factors that change plasma lipoprotein levels.
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From page 398... ...
More human studies are needed before conclusions can be drawn about whether dietary choline intake is useful in preventing cardiovascular disease. Cancer In rodents dietary choline deficiency is associated with increased incidence of liver cancer and increased sensitivity to carcinogenic chemicals (Newberne and Rogers, 1986~.
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From page 399... ...
or by clietary folate deficiency (Kim et al., 1994) resulted in climinisheci hepatic total choline, with the greatest decrease occurring in hepatic phosphocholine concentrations.
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From page 400... ...
Exercise Strenuous physical activity in trained athletes recluceci the plasma choline concentration by approximately 40 percent, from 14.1 to 8.4 ~mol/L (Conlay et al., 1986~. A choline supplement given to marathon runners modestly enhanced performance (Santiago et al., 1992~.
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From page 401... ...
In women consuming a low-choline diet, milk choline content is lower than that in women consuming a more adequate diet (Zeisel et al., 1982~. Consumption of either a choline-deficient or choline-supplemented diet by lactating rat dams results in significant changes in the phosphocholine concentration of their milk (Holmes-McNary et al., 1996; Zeisel et al., 1986)
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From page 402... ...
than floes either cow milk or infant formulas. However, cow milk and cow-milk-cleriveci infant formulas have the same glycerophosphocholine concentration as human milk (400 to 800 mol/L)
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From page 403... ...
No experimental attempts to make healthy women choline deficient have been reported. However, women on total parenteral nutrition were just as likely as were men to develop low plasma choline concentrations and fatty liver (Buchman et al., 1995)
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From page 404... ...
Choline availability cluring embryogenesis and perinatal clevelopment may be especially important. In rats feci acloquate cliets cluring pregnancy, postnatally, and at wearing, 1 mmol/day of extra dietary choline results in long-lasting enhancement of spatial memory
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From page 405... ...
Zeisel, University of North Carolina School of Public Health, unpublished observations, 1997~. At birth, humans and other mammals have plasma choline concentrations that are much higher than those in adults (Zeisel et al., 1980a)
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From page 406... ...
Choline Al Summary, Lactation AI for Lactation 14-18 years 550 mg/day of choline 19-30 years 550 mg/day of choline 31-50 years 550 mg/day of choline INTAKE OF CHOLINE Food Sources Choline is widely distributed in foods, with most of it in the form of phosphaticlylcholine in membranes. Foods that are especially rich in choline compounds are milk, liver, eggs, and peanuts.
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From page 407... ...
. Calculations of dietary choline intake are based on estimates of the free choline and phosphatidylcholine content of foods (Engel, 1943; McIntire et al., 1944; Weihrauch and Son, 1983; Zeisel et al., 1986)
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From page 408... ...
Studies of the production of methylamines from ingested choline suggest that fishy odor would have been observed in healthy populations (Zeisel et al., 1983~. Fishy body odor results from the excretion of excessive amounts of trimethylamine, a choline metabolite, as the result of bacterial action.
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From page 409... ...
Trimethylaminuria results from a rare genetic deficiency that causes excessive excretion of trimethylamine and, therefore, an increased risk of developing fishy body odor (Al-Waiz et al., 1988, 1989; Humbert et al., 1970; Shelley and Shelley, 1984~. Inclivicluals with renal or liver disease may have increased susceptibility because of increased levels of plasma choline (after ingestion of supplemental choline)
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From page 410... ...
At 7.5 g/day of choline, nausea, diarrhea, and a small decrease in blood pressure were reported in some patients. Other supportive data on cholinergic effects and fishy body odor after excess choline intake are summarized in Table 12-1.
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From page 411... ...
Gelenberg 5 8-19 g/dd 6-8 100% with fishy body odor et al., 1979e after several days; gastrointestinal irritation.f Lawrence 14 0.2 g/d 6 At 150 mg/kg/d: 5 of 14 et al., 1980g (3 wk) ; with fishy body odor; 12 of 9 g/d 15 with nausea and (3 wk)
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From page 412... ...
There are no ciata to suggest that cluring pregnancy or lactation increased susceptibility to developing cholinergic effects or fishy body odor from excess choline intake would occur. Therefore, the UL of 3.5 g/ciay is also set for pregnant and lactating women.
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From page 413... ...
This would include assessing plasma and tissue choline compounds and metabolites; plasma cholesterol and homocysteine concentrations; erythrocyte folate; and liver, renal, brain, and other organ function. To facilitate this process, food composition ciata are neecleci for choline, phosphocholine, glycerophosphocholine, sphingomyelin, phosphaticlylcholine, and betaine and the analytic sensitivity and specificity of methods for analysis of food composition neeci to be valiciateci.
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From page 414... ...
1996. Choline deficiency induces apoptosis in SV40-immortalized CWSV-1 rat hepatocytes in culture.
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From page 415... ...
1992. Lecithin increases plasma free choline and decreases hepatic steatosis in long-term total parenteral nutrition patients.
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From page 416... ...
choline deficiency and subsequent re-feeding of choline on 1,2-sn-diradylglycerol, fatty acids and protein kinase C in rat liver. Carcinogenesis 16:327-334.
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From page 417... ...
1996. Dietary choline supplementation in pregnant rats increases hippocampal phospholipase D activity of the offspring.
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From page 418... ...
1975. Evaluation of the Health Aspects of Choline Chloride and Choline Bitartrate as rood Ingredients.
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From page 419... ...
1997. Prolonged fasting in humans results in diminished plasma choline concentrations but does not cause liver dysfunction.
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From page 420... ...
1995. Choline deficiency and methotrexate treatment induces marked but reversible changes in hepatic folate concentrations, serum homocysteine and DNA methylation rates in rats.
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From page 421... ...
1988. The active synthesis of phosphatidylcholine is required for very low density lipoprotein secretion from rat hepatocytes.
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From page 422... ...
1989. Effect of choline deficiency on Sadenosylmethionine and methionine concentrations in rat liver.
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