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Acute, short-term hyperinsulinemia increases olfactory threshold in healthy subjects
1Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University Tübingen, Tübingen, Germany.
International Journal of Obesity (2005)
|November 25, 2010
Summary
High insulin levels impair smelling ability, potentially reducing appetite. This suggests insulin
Area of Science:
- Neuroscience
- Endocrinology
- Sensory Science
Background:
- Smell significantly influences feeding behavior.
- Insulin, a key postprandial hormone, may regulate olfactory function.
Purpose of the Study:
- To investigate insulin's role in regulating olfactory function.
- To determine if postprandial insulin affects smell perception.
Main Methods:
- Olfactory thresholds were measured in lean subjects during a 2-hour hyperinsulinemic euglycemic clamp.
- A control group of fasted subjects underwent the same procedure without insulin infusion.
- Standardized 'sniffing sticks' were used to determine odor thresholds.
Main Results:
- Odor thresholds significantly decreased (indicating increased sensitivity) during hyperinsulinemia (P=0.0173).
- The control group showed no significant change in odor thresholds after fasting.
- This suggests elevated insulin levels enhance olfactory perception.
Conclusions:
- Increased insulin levels enhance smelling capacity.
- Insulin's action in the olfactory bulb may contribute to satiation.
- This finding could be relevant to understanding obesity pathogenesis.
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