99E-2 |
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J. R. WILLIAMS1, J. C. Howe1, S. H. Zeisel2, M.-H. Mar2, and J. M. Holden1. (1) Nutrient Data Lab., USDA-ARS-Beltsville Human Nutrition Research Center, 10300 Baltimore Ave., Bldg 005, Rm 107, BARC-West, Beltsville, MD 20705, (2) School of Public Health, Univ. of North Carolina, Chapel Hill, Dept. of Nutrition, 2212 McGavran-Greenberg Hall, Chapel Hill, NC 27599-7461 Betaine, a choline derivative, is produced in the human body from choline and contributes methyl groups for the conversion of homocysteine to methionine. Elevated levels of plasma homocysteine can be harmful to blood vessels leading to the development of heart disease, stroke, and peripheral vascular disease. Betaine also assists the liver to process lipids and protect against chemical damages. Our objective is to develop the first comprehensive database determining the amount of betaine concentration in a nationally representative sampling of common foods consumed in the United States. Various food items were obtained from 12 – 24 retail outlets using the sampling plan developed for the USDA’s National Food and Nutrient Analysis Program (Pehrsson, P. et al. J. Food Comp. Anal 13:379, 2000). Products (530) were analyzed for betaine concentration as purchased or after cooking using liquid chromatography with electrospray ionization – isotope dilution mass spectrometry. Quality assurance methods included the use of duplicate sampling, in-house control methods and standard reference materials. Results show that of the foods analyzed, wheat bran and wheat germ have the highest concentration of betaine (>1gm/100g). Baked products (33 – 226 mg/100g), spinach, beets, crustaceans and finfish are also good sources of betaine. Meats, poultry, fruits, nuts, and wine are generally not good sources of betaine (<6 mg/100g). Since, baked products like bread, crackers, cookies and tortillas are also consumed in large quantities they are major contributors to betaine intake in the US diet. While alcoholic beverages, such as wine and beer, contain low to moderate levels of betaine, their high consumption rates make them key foods for betaine contribution in the US diet. Data on the betaine content of foods is presently very limited. Availability of the betaine content of foods will help determine the betaine intake of the US population, and facilitate research on the homocysteine/methionine pathway.
Session 99E, Nutrition: General II
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