Effect of Food Acceptability on Appetite Hormones' Response in Normal Weight vs. Obese Male Subjects

Male subjects were recruited for the study based on the following criteria: age between 18 and 50, body mass index normal or obese, non-smokers, non-alcoholic, and do not take medications. Subjects did an acceptability test on custard and completed a screening questionnaire. Around 30 subjects (15 with a normal BMI and 15 obese) continued the study. Subjects were randomly assigned to one of two meals. Each of the two meals was ingested after a 3-day adaptation period. The meals had similar macronutrient composition and provided energy equivalent to 30% of the subjects' resting energy expenditure. At each test day, fasting blood samples were withdrawn by a registered nurse under sterile conditions. This procedure was followed by ingestion of one of the two meals within a period of 10-15 minutes. Blood samples of 5 ml were collected at fasting and after ingestion of meals at 15, 30, 60, 120, 180 and 240 minutes. At the end, subjects were given ad lib access to cheese pizza to assess energy intake after the custard preload. Blood analysis for GLP-1, ghrelin, insulin and glucose levels were performed.

Inclusion criteria

• Gender: Male
• Age: 18-50 years
• Body Mass Index (BMI): 18.5-24.9 kg/m2 or 30-39.9 kg/m2
• Stable body weight for at least three months before the study with the absence of any form of dieting, food restriction or other abnormal eating behaviors (to minimize the effect of weight change on ghrelin and GLP-1 statuses)
• Agreement on the acceptability levels of the two versions (high and low acceptability) of custard

Exclusion criteria

• Smoking
• Substance abuse such as alcohol or drugs
• Medical or psychological illness
• Previous gastrointestinal surgery
• History of weight fluctuation (weight loss of greater than 5% within the past 3 months)