Prevention remains our best weapon to protect our memory and ward off cognitive decline. On the occasion of World Alzheimer’s Day this September 21st, Professor Philippe Amouyel, director of the Alzheimer’s Foundation, shares his key advice for preserving our “brain capital”.
“By the time the first symptoms of Alzheimer’s disease appear, it has already been progressing for more than 20 years,” explains Professor Amouyel, director of the Alzheimer’s Foundation and professor of public health. He continues, explaining that the reason it takes so long is that during this entire period, “the brain resists the disease’s attacks by compensating for neuronal loss.” Until the day this adaptive capacity reaches its limit: the symptoms appear.
Hence the importance of prevention to help the brain retain intellectual faculties for as long as possible, and ultimately to postpone the age of onset of symptoms.
What is “brain capital” and what is its link to Alzheimer’s disease?
Just as we have a “sunshine” finite, we have a “brain” finite. In practical terms, this means that our supply of neurons is not inexhaustible. From uterine life until around age 25, the brain develops to reach 80 to 100 billion neurons. After that, neuronal production slows considerably. However, brain activity doesn’t stop. “Our brain continues to function and learn, even after age 25, not through the production of new neurons, but through its capacity to make more connections. Knowing that one neuron can connect 10,000 other neurons, 100 billion neurons can generate 100 quadrillion connections!” Thanks to this complex network, the brain is able to perform tasks, learn, acquire new automatic skills, and so on.
The key is to foster these connections. “The more you exercise your brain, the more connections you make between your neurons, and the more you preserve your brain’s capacity, in other words, your cognitive reserve.” And the consequence, he continues, is that “the longer you maintain this capacity, the longer it will take for the brain to decline. In the case of Alzheimer’s disease, the onset of the first symptoms will be delayed.”
Memory problems: the first warning signs appear after age 45
According to Philippe Amouyel, we must be vigilant about the first signs of brain aging. The specialist explains that these signs of cognitive decline are normal, just as the first signs of aging appear, such as muscle loss or presbyopia . “Generally, it starts between 40 and 45 years old, with a classic sign: it’s the age when we start forgetting proper names or losing things!” While this often causes concern, it’s actually perfectly normal, he reassures us, as these lapses of memory rely on “pure” memory, as opposed to associative or repetitive memory. He then gives an example. “Imagine being introduced to Mr. X for the first time. You hear his name, but you’re not necessarily paying attention and you don’t make the effort to repeat his name in your head or associate it with another word to remember it. So you’re making a pure memory effort. If you run into him two days later on the street, chances are it will take you a while to recognize him. Even if that’s normal, it’s a clear sign that the brain isn’t as efficient anymore.”
In summary, from the moment you start to notice small signs of cognitive dysfunction, it’s the right time to start taking care of your brain, just as you would take care of your muscles, for example.
Preventing memory loss: here’s the best activity to keep your brain active
“Anything that stimulates the brain enriches cognitive capital,” summarizes Professor Amouyel. And the activity that stimulates it the most, according to him, is reading. Numerous studies based on functional MRI scans show that, when we read, different areas of the brain are activated, “like a Christmas tree,” he jokes.
Reading is the most comprehensive cognitive activity, as it engages numerous brain functions: it makes us think, imagine, anticipate, associate ideas, recall memories, and even experience emotions. “It doesn’t necessarily mean reading the entire Pléiade edition. You can read anything: a newspaper, a magazine, a comic book, a manga… and it doesn’t matter what the format is—paper, e-reader, phone—but read!” he insists.
Protecting yourself from memory problems means “stepping out of your comfort zone” and staying curious.
The second key to keeping your brain healthy for as long as possible is engaging in activities that push you out of your comfort zone. Why? When you learn something new, your brain has to expend more energy and create new neural connections. But once you’ve mastered the skill, your brain conserves energy by using shorter neural pathways. “So what I recommend is always staying curious and actively learning new things. Learning new languages, for example, is very effective for strengthening your brain . “
The doctor also shares a tip, accessible to everyone: “Are you right-handed? Take ten to fifteen minutes a day to do your daily activities with your left hand, and vice versa if you are left-handed. By doing this, it will “challenge” the brain, forcing it to create new connections. Ultimately, you will force it out of its comfort zone, which is very beneficial for keeping it fit in the long term.”
These everyday activities help to exercise your brain without you even realizing it.
Planning a trip, DIY projects, knitting, gardening, etc. All these seemingly mundane activities are very stimulating for the brain, confirms the memory specialist. The reason? They all require concentration and anticipation. “ Gardening, for example, even if it’s just on a balcony, involves researching watering frequency, buying potting soil, pruning plants at a specific time, etc., all with the goal of having beautiful flowers in the spring. So it projects you into the future, which is excellent for the brain. Conversely, watching TV for hours puts the brain on pause. That’s very bad because you become very passive.”
Is three cups of coffee a day excellent for the brain?
True. Provided you don’t have the last cup after 5pm.
These little-known enemies of the brain should not be underestimated
Protecting the skull. The brain is a fragile organ, suspended in cerebrospinal fluid within the skull, which protects it. However, any impact (sudden acceleration, sudden braking, a blow to the head, etc.) can cause the brain to move by a few tenths of a millimeter, and if repeated, can wear it down over time. This is evidenced by the observation that American football players have three times as many cases of Alzheimer’s disease as the general population. For this reason, wearing a helmet is essential when cycling, scootering, skiing, or horseback riding.
Avoid toxins that harm the brain. The brain is primarily nourished by glucose via the blood-brain barrier, which filters the blood. However, toxic substances can pass through and damage the brain: alcohol, tobacco, and drugs should be avoided.
Be careful with sleeping pills and antidepressants . Apart from pathological cases that require treatment, it’s important to know that taking antidepressants and sleeping pills can weaken the brain in the long term.
Don’t hold back your sneezing! Holding back a sneeze by plugging your nose increases pressure in the micro-vessels and micro-capillaries, which can then burst, creating micro-lesions in the brain.
Preventing cognitive disorders: a healthy mind in a healthy body
To maintain good health for a long time, the brain needs a fit and healthy body. Indeed, cardiac risk, broadly speaking, is associated with an accelerated onset of Alzheimer’s symptoms. This risk of having a heart attack or stroke is governed by a set of risk factors, including high levels of bad cholesterol , high blood sugar, high blood pressure, and excess waist circumference. All of these elements must be balanced and addressed.
Professor Philippe Amouyel advises: “From the age of 45, you should have a check-up and maintain or resume physical activity .” In addition, diet remains a crucial factor. According to the specialist, despite all the studies published regularly, there is one key takeaway, well-supported by robust research: favoring a Mediterranean diet . “It reduces cardiovascular and neurodegenerative risks by approximately 30%.”
Getting enough sleep is also essential, between 6 and 8 hours per night, and especially “restorative” sleep, which includes sufficient periods of deep sleep. Studies have shown that it is during this time that the brain eliminates the abnormal proteins that accumulate when Alzheimer’s disease develops. Furthermore, there is a correlation between snoring related to sleep apnea and the onset of memory problems. In fact, during breathing pauses, cerebral blood flow is reduced. Addressing these sleep apneas helps to mitigate this risk, the specialist emphasizes.
Sight, hearing… The 5 senses play a role in the development of memory disorders
The doctor also advises taking care of the five senses . “They are what connect our brain to the outside world.”
Vision. It is essential to correct the vision loss that naturally occurs with age (presbyopia) and to consult an ophthalmologist regularly to screen for any potential eye conditions. Indeed, poor vision limits our ability to receive information, which slows down brain function.
Hearing. Presbycusis, which can begin between the ages of 45 and 50, must be taken into account for the same reason: hearing loss limits brain function. Therefore, hearing aids , which have been fully covered by insurance since 2022, should not be overlooked.
Touch. Nothing replaces human contact, whether emotional or sexual; it is beneficial for maintaining brain health. Isolation and a lack of human contact are factors that contribute to Alzheimer’s disease.
Smell and taste are also important elements that contribute to good brain health.
Mood and social relationships: a key role in preserving memory
Having friends, social relationships, family ties, and interactions are all essential elements in preventing cognitive decline. In this regard, the expert emphasizes that retirement is “dreadful” for the brain . “Human interactions decrease and are all the more problematic for people whose work is their only social connection. Furthermore, retirement comes at an age when energy levels are declining. So, if you haven’t developed a habit of being active and if you are isolated, this creates a breakdown in social interaction, which is very detrimental to cognitive functions. Moreover, studies show that the earlier you retire, the more rapidly these functions deteriorate.”
Of course, this is not inevitable. Establishing a routine that combines enjoyable intellectual, social, and physical activities helps to keep cognitive functions active.
As Philippe Amouyel further points out, “optimists have 30% fewer cases of Alzheimer’s.”
To learn more:
Professor Philippe Amouyel is the author of the Anti-Alzheimer’s Guide: The Secrets of a Healthy Brain (published by Le Livre de Poche).
