The purpose of this research study is to determine how much choline healthy people need to have in their diets. Choline is a normal part of many foods. It is used in the body to make membranes (the wrappers around cells) and to make a nerve chemical called acetylcholine. Several species of animals need to eat choline; otherwise their livers do not work properly. It is not known whether this is so in humans because they may be able to meet their daily choline requirements by making choline in the liver. This study will test whether humans can make sufficient choline or not when they have less than the usual amount in their diet. This study will also examine whether a diet low in another vitamin, folate, will affect how much choline humans require.

The objective of this study is to determine the required daily amount (RDA) of choline, a nutrient deemed essential for humans, in adult men and women. At this time the Institute of Medicine has suggested an adequate intake, but has not determined the minimum intake of choline. Choline is used to form membranes (phosphatidlycholine), to form a neurotransmitter (acetylcholine), and as a methyl group donor in biochemical reactions. This report noted that choline is important for normal function, and that it is likely that humans require dietary choline. However, they noted that evidence in humans is insufficient to make accurate estimations of this requirement, and that " …research that could provide such human data is assigned the highest priority." The aim of this study is to determine the dietary choline requirement of adult men and women (pre- and postmenopausal).

Ages Eligible for Study:  18 Years   -   70 Years,  Genders Eligible for Study:  Both

Accepts Healthy Volunteers

Criteria

• Between the ages of 18 and 70
• For women, either postmenopausal or women of childbearing potential who are not pregnant or breastfeeding
• BMI less than 34
• No kidney or liver problems
• No alcohol or drug abuse
• No pacemaker, aneurysm clip, cardiac heart valve, mechanical devices or implants
• No other metal in body (i.e. injured by a bullet, BB, shrapnel, or metallic object)