The improvement of sweet taste sensitivity with decrease in serum leptin levels during weight loss in obese females

Area of Science:

• Metabolism and Endocrinology
• Sensory Science
• Genetics

Background:

• Leptin, a hormone regulating appetite and metabolism, may influence taste perception.
• The relationship between serum leptin levels, sweet taste sensitivity, and weight loss in humans remains under-investigated.
• Leptin receptor gene polymorphisms might affect metabolic regulation and taste sensitivity.

Purpose of the Study:

• To investigate alterations in sweet taste threshold and serum leptin levels during a weight-loss program.
• To explore the association between changes in leptin levels, sweet taste, and the Lys109Arg leptin receptor polymorphism.
• To determine if leptin levels correlate with sweet taste threshold changes during weight reduction.

Main Methods:

• A 12-week weight-loss program involving diet and exercise for 20 obese females.
• Determination of the sweet taste threshold using a whole-mouth gustatory method.
• Measurement of serum leptin levels and genetic analysis for the Lys109Arg polymorphism.

Main Results:

• Serum leptin levels significantly decreased from 9.2 to 7.9 ng/ml post-weight loss (p=0.014).
• The sweet taste threshold significantly decreased from 0.59% to 0.22% sucrose (p=0.004).
• Changes in serum leptin levels were significantly correlated with changes in the sweet taste threshold, irrespective of the Lys109 allele.

Conclusions:

• Weight loss in obese females leads to significant reductions in both serum leptin levels and sweet taste sensitivity.
• The observed decrease in sweet taste threshold during weight loss is associated with decreased serum leptin levels.
• The Lys109Arg polymorphism did not appear to influence the changes in sweet taste threshold during the weight-loss program.