2012 Annual Report
1a.Objectives (from AD-416):
The objective is to identify and quantify the choline containing components in representative samples of foods and dietary supplements. These data will improve and expand USDA nutrient databases such as the Nutrient Database for Standard Reference, which is released on the Nutrient Data Laboratory website, and the Nutrient Database for Food Consumption Surveys.
1b.Approach (from AD-416):
The Nutrient Data Laboratory (NDL) is responsible for developing and disseminating authoritative food composition databases of foods in the U.S. diet. NDL has developed a Key Food approach to help establish priorities for foods to be analyzed. Key Foods are those identified as contributing up to 75% of any one nutrient of public health significance. Key Foods form the core of foods to be analyzed, supplemented by other foods deemed of particular interest due to their frequent use as ingredients or content of nutrients of emerging interest. Sampling plans will be developed for each type of food sampled, to assure a representative sampling of the food supply. Samples of food will be delivered to the Cooperator for analysis. In some cases the Cooperator may need to develop food matrix specific methods for handling and analyzing samples and preparing aliquots for shipment to other researchers for analysis of additional food components. The Cooperator will also offer expertise in interpretation of results of the choline components analyses.
Choline is needed for normal cell function, assists in the metabolism of fat and cholesterol, and prevents fat accumulation in the liver. Betaine, a derivative of choline, is important for its role in the donation of methyl groups used in the conversion of homocysteine to methionine. While the U.S. Institute of Medicine, in 1998, made recommendations for choline intake, estimating an Adequate Intake (AI), committee members also indicated a high priority need for data on choline composition of foods and choline intake in the U.S. population. The development and release of the USDA Database for the Choline Content of Common Foods in 2004 provided researchers and consumers with the means to estimate choline intake. In January 2008 the Nutrient Data Laboratory (NDL), in collaboration with scientists at the University of North Carolina (UNC), released on the NDL web site (www.ars.usda.gov/nutrientdata) an updated version of a Special Interest Table for 640 foods (USDA Database for the Choline Content of Common Foods, Release 2). During FY 2012 UNC was sent for analysis 55 composites of different food samples and control materials, including turkey and chicken samples, cereals, deli meats, mayonnaise, fast food items, baked beans, baked items, and entrees. Choline values for 20 composites were entered into the NDL databank system and compiled for release in Nutrient Database for Standard Reference (SR)25. Values for the remaining composites will be entered at a later date for release in SR26. Occasional conversations and e-mails with both the analytical chemist and the primary investigator at the cooperating laboratory were held to answer any questions relating to the data. Data from this project have been used by the research community in epidemiological studies and to establish a relationship between choline and betaine intake and the etiology of neural tube defect.