Have you ever wondered why biting into a slice of pizza on a rumbling stomach makes it taste better than usual?
Well, according to science, food does taste stronger when you are hungry!
New research shows that hunger can increase our smell perception by modifying specific receptors in our brains, thus increasing our food intake.
Enhanced Sense of Smell
According to a study published in Nature Neuroscience, hunger triggers the activity of endocannabinoid receptors. This activates the olfactory circuit to become more responsive. The circuit is located in the forebrain that receives neural input about odours from the cells in the nasal cavity and is responsible for our sense of smell.
The endocannabinoid system (ECS) is a neurotransmission system of a series of cell receptors throughout the body. In mammals, the endocannabinoids are located in the brain and in the central and peripheral nervous systems.
The ECS plays a central role in the limbic system by regulating food intake and energy balance.
Led by research director Giovanni Marsicano of the French National Institute of Health and Medical Research, the team behind the study explained that hunger triggers a set of mechanisms that encourage feeding by increasing sensory perceptions such as the sense of smell. However, they noted that these findings still remain poorly understood.
Increased Sensitivity to Sugar and Salt
A research published in BMC Neuroscience, suggests that hunger affects the taste of food by making peckish people more sensitive to sweetness and saltiness. It increases the sensitivity of the taste receptors on your tongue and affects the way you perceive the same taste stimuli.
Professor Yurity P. Zverev from the University of Malawi investigated how overnight fasting affected the taste buds of healthy males who neither smoked nor drank.
In the experiment, participants had to skip breakfast and were tested on their ability to taste salty, sweet and bitter solutions of varying concentrations. The test was repeated later in the day after having lunch.
It was shown that when hungry, the men were more sensitive to the presence of sugar and salt, but their ability to detect bitter compounds remained unchanged.
Zverev suspects that this difference is due to the different roles that tastes play. He explained that “while sweet and salty tastes are indicators of edible substances and trigger consumption, a bitter taste indicates a substance which is not suitable for consumption and should be rejected.”
Hunger and taste are the mechanisms that evolved to encourage you, and indeed all animals, to eat what your body needs most. When you have used up all your available energy, you will tend to crave sweet foods and carbohydrates.
If you are starved of protein, you will find meat, fish and other protein-rich foods especially tasty. This could explain why pregnant women often enjoy completely different foods from normal because their growing baby needs different things.