Endocrine Abstracts

Background: Obese subjects are usually in a positive energy balance despite their best efforts to lose weight. This study aimed to determine if hunger, nausea and satiety levels differ in lean and obese subjects after consuming varying calorific meals.

Method: Following an overnight fast, test meals of 250, 500, 1000, 2000 and 3000 kcal were consumed by 19 lean and 19 obese subjects. Hunger, nausea and satiety levels were measured using visual analogue scales (VAS) in the fasting state and postprandially at 30 and 180 minutes. Proportional changes in hunger, nausea and satiety were calculated allowing evaluation of changes in the levels relative to that in the fasting state. Statistical analysis was performed using the Wilcoxon two sample test to account for the small sample sizes and variability of the data.

Results: The proportional change in satiety experienced by obese subjects was significantly less than lean subjects in response to a 1000 kcal meal (30 min P < 0.05, 180 min P < 0.01), a 2000 kcal meal (30 and 180 min P < 0.01) and 3000 kcal meal (30 and 180 min P < 0.01). No differences in proportional changes in hunger were detected. However, whilst not statistically significant, it was interesting to note that obese subjects almost always had higher mean proportional changes in nausea scores at 180 minutes post ingestion.

Conclusion: The possible trend in this study towards obese subjects feeling more nauseous than lean subjects may indicate that the obese subjects were actually less familiar with high fat and sugary foods. This suggests avoidance behaviour consistent with perpetual dieting. No differences in hunger levels were detected between the two groups. Obese subjects felt less full after consuming the same volume and quantity of calories than their lean counterparts. Increasing satiety may therefore be a relevant therapeutic goal for obesity.