Our attraction to fatty foods suggests a genetic predisposition to love fat, associated with survival. In fact, fats contain, on an equal weight basis, twice as many calories as sugars or proteins. The attraction towards foods rich in fat would be due to a receptor called CD36 present in the tongue. Olive oil, nuts, fish, omega 3, only good for health.
The pleasure we experience in eating food is due to the presence of detection systems that connect the nose and mouth to certain specific regions of the brain. Three main parameters are evaluated by these systems:
- Taste: Present on the tongue, the sense of taste has the function of recognizing the substances essential to the proper functioning of our body. So far, five types of tastes have been characterized, namely those of sugar, salt, umami (proteins), bitter and acid.
- Flavor: The aromas released in the mouth during chewing are captured at the nose and this detection is absolutely essential to appreciate the flavor of food. It is estimated that 85% of the perception of taste is due to smell, which explains why we taste practically nothing during nasal congestion caused by a cold.
- Texture: The presence of food in the mouth exerts several physical stimuli, whether in terms of temperature or texture. These properties, called somatosensory, are very important because they give the food its palatability, that is, the pleasant sensation that is associated with its consumption.
Our brain loves fat
Fat is without doubt one of the substances that exert the most influence on the palatability of a food. As it dissolves in the mouth, the creamy texture of the fat stimulates the trigeminal nerve in the mouth to signal to the brain the presence of an important source of calories. This signal is generally interpreted in a very positive way because, throughout evolution, the scarcity of food has caused the brain to specialize in detecting sources of calories to ensure survival. Consequently, even if we currently live in an overabundance of food, this ancestral reflex remains present and very often pushes us to look for the presence of fat in a food.
In addition to its texture, work done in animal models has suggested the presence of a fat-specific receptor, called CD36, in the tongue. To determine whether this receptor played a similar role in humans, a team of researchers asked volunteers to blindly taste three solutions: the first contained a small amount of fat while the other two had identical textures, but without however containing fat.
In parallel, a blood sample was taken and analyzed to determine the sequence of the gene coding for the CD36 receptor.
The results obtained are interesting: the participants who possess a version of the CD36 gene which allows the production of a greater quantity of this receptor were 8 times more sensitive to the presence of fat in the solutions tested. In other words, the attraction towards foods rich in fat would not only be due to the unique texture of fat in the mouth, but also to the presence of specific receptors for this substance in the tongue.
We naturally like fat and it’s good for our health
These findings are important because other studies indicate that this greater fat-sensing ability is associated with a strong behavioral preference for choosing high-fat foods.
But whether we are genetically predisposed to appreciate fat or not, we must remember that it is much more the quality of these fats than their quantity that matters. In this sense, favoring the consumption of good fats such as olive oil, nuts or fish such as salmon is the best way to fully satisfy our brain’s inclination for fat, while promoting health. and well-being.
Source
Keller KL. Genetic influences on oral fat perception and preference. J Food Sci. 77: S143-7.
