A Comparison of the Neurocognitive and Metabolic Effects of Fructose, Glucose, High Fructose Corn Syrup and Sucrose at Normal Population Consumed Levels in Adults Ages 20-60 Years Old

Inclusion Criteria: * Male or female between the ages of 20-60 years of age. * Body Mass Index (BMI) 21.0 - 35.0 Exclusion Criteria: * More than a 3 percent change in weight within the 3 months prior to enrollment in the study. * History of thyroid disease, but not taking medication or medication dosage changed one or more times over last 6 months. History of thyroid disease and on a stable dose of prescription medication for 6 months or longer is acceptable. * Currently taking a prescription medication for weight loss. If subject is willing to discontinue prescription medication(s) immediately and willing to refrain from taking medication(s) for duration of study, he/she may be enrolled after a four-week washout period. * Currently taking any over-the-counter weight loss supplement(s). If subject is willing to discontinue supplement(s) immediately and willing to refrain from taking supplement(s) for duration of study, he/she may be enrolled after a two-week washout period. * Currently enrolled in commercial weight loss program (e.g. Jenny Craig, Weight Watchers) or self-help group (e.g. TOPS, Overeaters Anonymous). If subject is willing to discontinue program immediately and willing to refrain from program for duration of study, he/she may be included after a two-week washout period. * Diagnosed with prediabetes or frank diabetes (Type I or Type II). * History of major surgery within three months of enrollment. * History of heart problems (e.g. angina, bypass surgery, MI, etc.) within three months prior to enrollment. * Presence of implanted cardiac defibrillator or pacemaker. * Uncontrolled hypertension/high blood pressure. * History of a surgical procedure for weight loss at any time (e.g. gastroplasty, gastric by-pass, gastrectomy or partial gastrectomy). * Gastrointestinal disorders including chronic malabsorptive conditions, peptic ulcer disease, Crohn's disease, chronic diarrhea or active gallbladder disease. * History of inflammatory bowel disease * History of fatty liver * History or presence of cancer. Persons with successfully resected basal cell carcinoma of the skin may be enrolled if treatment completed more than 6 months prior to enrollment. * History of clinically diagnosed eating disorders including anorexia nervosa, bulimia nervosa or binge eating disorder. * Women who are pregnant, lactating or trying to become pregnant. * Currently taking any prescription medication for less than 3 months. * Currently consuming \>14 alcoholic drinks (1 drink = 12 fl oz beer, 4 fl oz wine or 1.5 fl oz liquor) per week and/or unwilling to limit intake to less than 3 drinks per week during study participation. * Known allergy to HFCS, sucrose, fructose or glucose. * History of alcohol dependency * Participation in another clinical trial within 30 days prior to enrollment. * Lactose intolerance * Currently smoking cigarettes * Any clinically significant food allergy