Routine, the neuron killer
At what age does the brain start to age?"When we're born", answers Jacques Touchon. It's an inescapable process, but one that can be slowed down with a simple cocktail: intellectual stimulation, physical activity, social contact and a Mediterranean diet.
As skin ages, wrinkles appear. When hair ages, it turns gray, then white, or sparse. But when the brain ages, what happens? "The speed of information processing decreases, it becomes more difficult to do several things at once and to focus attention."explains Jacques Touchon. Why is this? For a long time, it was believed that our stock of neurons was fixed at birth, and that it would inevitably diminish over time, leading to a decline in cognitive capacity. "But we now know that this is not the main cause of cerebral ageing and that new neurons can appear in certain structures such as the hippocampus".says the neuropsychiatrist.
Mysterious aging
So why does the brain age?Cerebral aging is still something of a mystery," answersJacques Touchon. But we do know that the brain bears the scars of all the trials and tribulations of life". Cerebral trauma, vascular lesions, the effects of toxic substances such as alcohol - these are just some of the factors that accumulate over the course of a lifetime and have an impact on brain function. Just as some people see their hair fall out as soon as they enter adulthood, while others keep a full head of hair for the rest of their lives, we are not all equal when it comes to brain ageing. "We don't all have the same genetic equipment to resist the aging process," explains Jacques Touchon.
While we can't change our genetic capital, we can help slow down the aging process... How? Thanks in part to a phenomenon known as cerebral plasticity. "If the brain is stimulated, it develops new synaptic connections and new networks," explains Jacques Touchon. In this way, we build up a ʺcerebral reserveʺ that compensates for the alteration in functional networks caused by brain damage." A reserve that is built up from childhood and can continue to be fed throughout life.
Stimulate your brain
And there's no mystery to stimulating the brain: you have to use it. "Those who have practised intellectual exercise all their lives have a lower risk of developing Alzheimer's disease, a pathological form of cerebral ageing which leads to memory and behavioural disorders and progresses to dementia", illustrates the neuropsychiatrist. This disease is characterized by abnormal deposition in the brain of two proteins that cause lesions. "People who have stimulated their brains throughout their lives may well have deposits of these proteins, but in them this does not cause deterioration in cognitive functions," explains Jacques Touchon. Well-trained brains in fact "compensate" for these lesions thanks to their extraordinary neuronal plasticity, which remains the best weapon against aging.
"If the brain is stimulated, it develops new networks".
It's a weapon you shouldn't hesitate to draw, even in the absence of any illness: "Elderly people who take part in intellectually stimulating leisure activities have a significantly slower rate of cognitive decline", adds Jacques Touchon. Intellectually stimulating leisure activities? "Playing bridge, doing crosswords, reading or attending a senior citizens' club. According to the specialist, the situation that most stimulates the brain is meeting new people and experiencing new things. "If tomorrow is the same as today, then the brain is at risk".
Your brain's enemies
Every time our brains are damaged, they age. Can we preserve our youth by limiting their appearance? "It's possible by reducing vascular risk factors, the main culprits behind the appearance of brain lesions," answers Jacques Touchon. Preventing or correcting high blood pressure, cholesterol, diabetes, obesity, stress, a sedentary lifestyle, smoking and alcohol all help to slow brain ageing. Researchers have also found that regular physical activity helps slow cognitive decline.
The virtues of the Mediterranean diet
Studying the relationship between vascular risk factors and dementia: this is the aim of the work known as the "Three Cities Study". Starting in 1999, 10,000 people aged over 65 were monitored for 10 years in Montpellier, Bordeaux and Dijon. By studying the dietary habits of the participants, the researchers found that those who followed a Mediterranean-style diet were less likely to experience a decline in their cognitive abilities. "This type of diet slows down the aging of the brain", explains Jacques Touchon. On the menu: fruit, vegetables and fish seasoned with a good dose of olive oil, accompanied by one or two glasses of red wine a day. Where do the virtues of the Mediterranean diet come from? "Probably the micronutrients found in this type of diet, such as omega-3s and vitamins B and E, which have an antioxidant action and help limit brain damage.