Eating an unbalanced diet can lead to brain changes that contribute to the onset of depression and anxiety, a new study suggests.
- Poor diet can lead to brain changes associated with depression and anxiety.
- glutamate – two neurotransmitters. A reduction in gray matter is also observed in the frontal area of the brain.
- When a person eats fatty and sugary foods, there is a decrease in gamma-aminobutyric acid (GABA) and an increase in glutamate – two neurotransmitters. A reduction in gray matter is also observed in the frontal area of the brain.
- These changes are also associated with mental rumination, a symptom of depression and anxiety, the study found.
Food helps to provide energy to the brain and ensure its functioning. But be careful, if the food chosen is not healthy… it will be sad. A study from the University of Reading, Roehampton University, FrieslandCampina (Netherlands) and Kings College London shows that an unbalanced diet rich in sugar and saturated fats can lead to brain changes associated with depression and anxiety.
Junk food: changes in neurotransmitters and gray matter volume
To determine the link between food intake and mental health, the researchers performed brain scans on college students. They revealed changes in neurotransmitter levels and gray matter volume in those who ate junk food compared to those who ate a Mediterranean diet, which is considered very healthy.
In addition, the team of works published in Nutritional Neuroscience found that these brain changes were linked to mental rumination, a symptom associated with depression and anxiety.
“When a person has a poor quality diet, there is a reduction in gamma-aminobutyric acid (GABA) and an increase in glutamate – two neurotransmitters – as well as a reduction in the volume of gray matter in the frontal area of the brain. This could explain the association between what we eat and how we feel.”they write in their communicated.
The front part of the brain is, in fact, “implicated in mental health issues such as depression and anxiety,” says Dr Piril Hepsomali of the University of Reading, who took part in the study.
How do fatty and sugary foods affect the brain?
While an association has been found, it remains to be seen how exactly poor diet affects the brain. “It is possible that obesity and diets high in saturated fat cause changes in glutamate and GABA metabolism and neurotransmission, as shown in animal studies.”the researchers say.
The other track is quite far from the brain: the microbiota, which is an important producer of neurotransmitters (including GABA), would perform its role less well because of the alterations it undergoes during an excess of fatty or sugary products. “A diet high in saturated fat and sugar has also been shown to reduce the number of parvalbumin interneurons, which play the role of transporting GABA to where it is needed.”add the authors.
Additionally, an unhealthy diet promotes increased blood sugar and insulin levels. “This increases glutamate in the brain and plasma, thereby reducing the production and release of GABA.”
Dr. Hepsomali explains: “I would like to note that GABA and glutamate are also intimately involved in appetite and food intake. A decrease in GABA and/or an increase in glutamate could also be a determining factor in unhealthy food choices. So there may be a circular relationship between eating well, having a healthier brain and better mental well-being, and making better food choices to eat well.”