Research

Hormonal

Fasting and metabolic states modulate olfactory sensitivity by upregulating metabolic hormone receptors (insulin, leptin, NPY) in the olfactory mucosa and bulb, enhancing odor detection during hunger.

If you feel your sense of smell is sharper when you are hungry, this is a normal biological response. Your body upregulates receptors for hormones like insulin and leptin in your nose to help you find food. This is not a flaw in your discipline; it is a designed feature of your metabolic system.

GoodSupportsHIGH confidence
Fasting results in an increased ability to detect odors, some of which are food-related, whereas satiety with one type of food reduces the ability to detect the odor specially associated with that type (O’Doherty et al. 2000; Mulligan et al. 2002)... IR kinase and Ob-R transcript levels in the OM are upregulated by a 48-h fast, which results in an increase of IR number (Baly et al. 2008; Lacroix et al. 2008).
Brigitte Palouzier‐Paulignan et al. · Chemical Senses · 2012

Why this rating

The paper is a comprehensive review citing multiple primary studies across species, though it lacks a single definitive clinical trial.

Source

Olfaction Under Metabolic Influences

Brigitte Palouzier‐Paulignan et al. · Chemical Senses · 2012

DOI 10.1093/chemse/bjs059

narrative_reviewCited 316×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →