This book provides reference points for researchers, clinicians and educators for assessing obesity in different individuals and populations. It serves as a ready reference for selected measures of weight, nutrition and dietary intake, activity and exercise, behavior, well-being, and disease risk relationships. It presents assessment tools, along with their applications and practical interpretations. Emphasis is given to the differences by age, gender, weight status and the many interrelated variables that contribute to the development and/or exacerbation of the obese state. Comprehensive coverage includes: a series of baseline assessment questionnaires designed to assess activity, nutrition, health, demographics and weight; descriptions of methodology and reference standards for age, gender and weight related variables relative to a healthy population of adults; state-of-the-art measurements of nutrition and dietary intake assessments; the methodology and assessment of sleep activity and exercise in normal and obese men and women; selected questionnaires to assess the behavior and health of obese and normal weight individuals, particularly in their predictive value for successful weight maintenance; routine measures of laboratory assessment, presenting normative values for which to compare obese and normal weight healthy individuals; special procedures and considerations unique to epidemiological studies and maintaining subject participation and compliance.