Alzheimer’s and depression: the fault also with junk food!

We already knew that junk food, embodied by fast food and ultra-processed foods, was particularly harmful to physiological health, leading to obesity, diabetes, cardiovascular disease and even cancer.

But it would also be a plague on mental health, according to a recent study published in the journal Metabolic Brain Disease.

Physical disorder… and therefore psychiatric

Diseases resulting from a diet excessively composed of fatty, salty and sugary foods could indeed be the cause of certain mental pathologies such as anxiety, depression and even Alzheimer’s disease.

“Obesity and diabetes impair the central nervous system, exacerbating psychiatric disorders and cognitive decline”, explains to ScienceAlert neuroscientist Larisa Bobrovskaya of the University of South Australia, one of the study’s authors. She adds that these pathologies are “often associated with Alzheimer’s disease” or even to “dementias”.

Depressed mice

To reach these conclusions, the researchers carried out experiments on two groups of mice, one composed of lambda subjects, the other of subjects presenting a mutation of the Tau protein – whose abnormal accumulation in humans would be involved in metabolic disorders related to Alzheimer’s, according to Inserm in 2017.

The two groups of rodents were then subjected either to a diet made up of junk food, or to a conventional diet, for 30 weeks (i.e. almost half of their life, knowing that these laboratory mice live on average 18 months) .

The results are clear: in addition to gaining weight, ordinary mice fed junk food are more likely to show signs of anxiety and to have high levels of Tau protein in the brain. For mice already presenting a mutation of said protein, the consequences of the unhealthy diet on their health are all the more disastrous. “They were even more likely to gain weight, develop glucose intolerance and insulin resistance, suffer from depression and anxiety behaviors, and their brains showed higher levels of tau protein.” than before the diet, reports ScienceAlert.

Memory also affected

In the same vein of cognitive decline, it turns out that eating too much fat and sugar also permanently degrades – and in the space of just a few days – our memory, according to a study published in 2020 in the journal Royal Society Open Science. In question, a “altered hippocampus, a brain region involved in memory and appetite control”, according to one of the researchers quoted by The Guardian.

To minimize the risk of obesity and diabetes, and therefore of mental pathologies, it is advisable to follow a balanced diet, practice regular physical activity, get enough sleep, but also stimulate your brain, both intellectually and mentally. social.