Evaluating Hunger and Satiety at RLI

What is satiety?
Satiety refers to the feeling of satisfaction or fullness after consuming a meal or snack. Satiety is related to appetite regulation, hunger and the control of food intake.

Why does RLI evaluate satiety?
Appetite regulation is an important aspect of body weight management. For example, during intentional weight loss, preventing excess hunger and maximizing the level of satiety after and between meals can help make adherence to a diet more possible. Some scientists have found that levels of blood sugar and the hormone insulin may be involved in appetite regulation. Different foods may cause different responses in blood glucose and insulin, and different people may respond differently to the same foods under certain conditions. Some components of foods that may affect such responses, and thus hunger and satiety, include protein content, water content, different types of fiber, and the glycemic index. Therefore, at RLI we perform tests to help evaluate what determines these responses to help us understand how and why people become hungry and satiated. This may assist us and other scientists in discovering what are the best foods for body weight management.

How does RLI test satiety in a clinical setting?
One test of appetite regulation is called the Clinical Satiety Protocol. In this test, two types of breakfasts are compared on separate mornings before and after participation in a diet and/or exercise study. Volunteers come to the laboratory in the morning after fasting overnight for 10 hours. During the test, before and after eating the breakfast, the research volunteer completes questionnaires about hunger and satiety, and has blood samples drawn for glucose and insulin. The Senior Research Nurse places an indwelling catheter in the research volunteer's arm to obtain these blood samples and decrease the number of needle sticks. Questionnaires and blood samples are obtained at the following number of minutes after the meal: 15, 30, 45, 60, 90, 120, 150 and 180. During the three hours of testing, volunteers are free to read, write and/or listen to music, and a research staff member is always present.

Another way that appetite regulation is evaluated during studies at RLI is through the Daily Appetite Profile. This is a questionnaire that volunteers take home to complete over the course of three days. At certain times of the day, volunteers rate how hungry and satisfied they are. This information helps us to understand patterns of appetite in real-life settings.