Cognitive Health 2/2: The Pillars That Support Your Brain

This article is Part 2 of our two-part series on cognitive health across the lifespan, developed alongside our podcast episode with William Kadmiry and Anaïs Gautron. If you missed it, start with Part 1: what cognitive health really means and the early signs worth watching.

In Part 1, we explored what gradually weakens the brain: inflammation, oxidative stress, insulin resistance, sleep debt, hormonal dysregulation, the gut-brain axis, vascular health and loss of cognitive resilience.

This second part focuses on the levers. The goal: to understand what truly supports memory, focus, neuroplasticity and mental clarity over time.

The most interesting interventions are not isolated. They combine movement, sleep, nutrition, metabolic stability, cognitive stimulation and social connection.

1. Movement: the most powerful lever

Physical activity is one of the best-documented pillars for preserving cognition because it acts on several mechanisms at once: cerebral blood flow, insulin sensitivity, low-grade inflammation, mood, sleep and neuroplasticity.

Aerobic exercise

Brisk walking, cycling, swimming, sustained hiking: aerobic exercise refers to continuous effort that raises the heart rate enough to stimulate cardiovascular adaptation.

It improves cerebral blood flow, oxygen delivery to neurons and vascular function. It also supports insulin sensitivity and helps modulate low-grade inflammation, two mechanisms strongly linked to cognitive health.

Aerobic exercise also increases certain factors involved in neuroplasticity, such as BDNF, a protein that supports neuronal survival, synaptic plasticity and learning.

Target: 150 minutes per week of moderate activity, for example 30 minutes of brisk walking, 5 times per week. Intensity also matters: aim for at least Zone 2.

Strength training

Muscle is an active organ. It absorbs a large portion of glucose after meals, improves insulin sensitivity, secretes myokines involved in muscle-brain communication and protects against age-related loss of lean mass.

This matters because a brain exposed to unstable blood sugar, insulin resistance or chronic inflammation is not operating in an optimal environment. These mechanisms can affect brain energy, vascular function, neuroinflammation and mental clarity.

Preserving muscle mass is therefore not only about protecting the body. It also supports a more favorable metabolic terrain for the brain.

Target: 2 to 3 strength sessions per week, using the main movement patterns: push, pull, squat, hinge, carry and stabilize.

2. Sleep: what consolidates

Sleep allows the brain to sort, stabilize and integrate part of the information learned throughout the day. It also contributes to the clearance of certain metabolic waste products through the glymphatic system.

Insufficient or fragmented sleep can quickly translate into less reliable memory, unstable attention, brain fog, stronger emotional reactivity, difficulty learning and cognitive fatigue.

Duration matters, but it is not enough.

Eight hours of sleep with frequent awakenings, alcohol, sleep apnea, pain, hot flashes or unstable blood sugar will not have the same effect as deep, regular sleep.

Concrete anchors: a stable wake time, natural light in the morning, caffeine stopped 8 to 10 hours before bed, a cool bedroom, a dinner that is nourishing but not too heavy, reduced bright light in the evening, and no alcohol used as a "sleep aid".

Worth investigating: snoring, dry mouth, morning headaches, frequent awakenings or waking up tired.

3. Nutrition: giving the brain its raw materials

The brain needs lipids for its membranes, amino acids for neurotransmitters, B vitamins for myelin and methylation, minerals for nerve signaling, polyphenols to modulate oxidative stress and inflammation, and stable energy to function well.

Omega-3s

DHA contributes to the structure of neuronal membranes. EPA is more involved in inflammatory modulation.

The most interesting sources include sardines, mackerel, herring, anchovies, salmon, trout, omega-3-enriched eggs and microalgae oil as a direct plant-based source of DHA/EPA.

Target: 2 portions of fatty fish per week, or testing the omega-3 index to objectify status.

B vitamins and homocysteine

B6, B9 and B12 contribute to neurotransmitter synthesis, myelin and homocysteine regulation. Elevated homocysteine may reflect a less favorable terrain for the brain, particularly in terms of vascular health and methylation.

Sources: B12 in eggs, fish, seafood and meat; B9 in leafy greens, fresh herbs, lentils, chickpeas and avocado; B6 in poultry, fish, potatoes, chickpeas and bananas; choline in egg yolks, liver, fish and soy.

Protein

Protein provides the amino acids the brain needs to produce part of its neurotransmitters.

• Tyrosine → dopamine and norepinephrine: motivation, attention, mental drive.

• Tryptophan → serotonin and melatonin: mood, calm, sleep.

• Choline → acetylcholine: memory, learning, attention.

• Glycine and glutamine → nervous system regulation.

These conversions also require cofactors: vitamin B6, folate, B12, iron, zinc and magnesium.

Insufficient protein intake, especially at the first meal, may contribute to more unstable mental energy, cravings for sugar or caffeine, fluctuating concentration and poorer recovery.

Target: a real source of protein at every meal, starting with the first meal of the day: eggs, fish, poultry, quality meat, Greek yogurt or cottage cheese if tolerated, tofu, tempeh, lentils, chickpeas and beans.

Polyphenols

Polyphenols help modulate oxidative stress, inflammation and certain pathways involved in synaptic plasticity. Part of their effect also depends on the gut microbiome, which converts them into active metabolites capable of influencing the gut-brain axis.

They are found in blueberries, blackberries, raspberries, pomegranate, unsweetened cacao, green tea, coffee if well tolerated, extra-virgin olive oil, herbs, turmeric, ginger, cinnamon, red onions, citrus fruits, colorful vegetables and spices.

Target: add one source of polyphenols to every meal. For example: fresh herbs and olive oil on a dish, berries at breakfast, unsweetened cacao in yogurt, green tea during the day, spices in a sauce or highly colorful vegetables on the plate.

4. Cognitive stimulation: getting out of autopilot

Brain plasticity is stimulated more when an activity requires the brain to adapt, not simply repeat what it already knows how to do.

The key elements: novelty + attention + effort + feedback + repetition.

This can include learning a language, an instrument, a text, a technical movement, a sport requiring coordination and precision, or writing, drawing, dancing, chess, active memory work or learning a new professional tool.

The activity should be difficult enough to require real engagement, but not so difficult that it becomes discouraging.

Rereading, listening passively or always repeating the same task mostly maintains existing circuits. Testing yourself, reformulating, correcting mistakes and repeating with attention strengthens learning more effectively.

5. Social connection, hearing and vision: the forgotten pillars

Cognition also depends on the quality of the stimulation the brain receives.

A conversation mobilizes attention, language, working memory, mental flexibility, emotional reading and stress regulation. Conversely, social isolation is recognized as a modifiable risk factor for cognitive decline.

Two other levers are often neglected: hearing and vision.

When hearing declines, the brain has to work harder to decode sounds. This cognitive load leaves fewer resources available to understand, remember and fully participate in the exchange.

When vision is poorly corrected, reading, mobility, independence, physical activity and social interactions can all decline.

Testing hearing and correcting vision may seem secondary. Yet these actions reduce cognitive load and preserve access to the stimulation the brain needs.

6. Stress and cognitive overload: protecting attention

Acute stress can be useful. The problem appears when it becomes chronic. Over time, a high stress load can disrupt sleep, blood sugar, inflammation, memory and the brain's ability to return to balance.

But today, another factor weighs heavily: constant cognitive overload.

Notifications, messages, multitasking, meetings, noise, social media, podcasts, open tabs, constant demands: the brain receives too much input, too often, without real recovery phases.

If the brain spends the entire day repeating: interrupt, check, scan, respond, switch from one topic to another, it becomes more efficient at doing exactly that. But not necessarily at staying focused, going deep, remembering or creating.

Simple actions: schedule one 25- to 45-minute block without notifications each day, keep your phone out of sight during deep-focus tasks, take a screen-free break between work blocks, sometimes walk without a podcast, avoid starting the day with messages, batch response-based tasks and keep a window without stimulating content before bed.

The goal is not to remove all stimulation. The goal is to stop training the brain to be interrupted constantly.

Biomarkers to monitor

We can objectify the terrain in which the brain is operating.

Useful markers: omega-3 index, homocysteine, B12, folate, 25-OH vitamin D, fasting insulin / HOMA-IR, HbA1c, ApoB, advanced lipid panel, hs-CRP, ferritin, thyroid panel, cortisol and DHEA-S.

These markers help assess whether the brain is operating in a terrain that supports mental clarity, repair and adaptation.

Where to start? Your 4-week plan

| Week | Priority | Actions | | --- | --- | --- | | 1 | Mental energy | Add a real source of protein to your first meal. Walk 10 minutes after your most carbohydrate-rich meal. Add one source of polyphenols to each meal. | | 2 | Movement | Aim for 2 to 3 moderate endurance sessions of 30 minutes. Add 2 to 3 strength sessions. | | 3 | Sleep and attention | Stabilize your wake time. Get natural light in the morning. Stop caffeine 8 to 10 hours before bed. Schedule one notification-free block per day. | | 4 | Neuroplasticity | Choose a slightly difficult skill. Practice 15 to 20 minutes, 4 times during the week, using active recall: test yourself, reformulate, repeat without looking. |

What to remember

The most useful levers for the brain are not necessarily spectacular.

They are often simple actions, repeated consistently, that change the terrain: moving enough, preserving muscle mass, sleeping more consistently, supporting blood sugar, getting enough protein, omega-3s, B vitamins and polyphenols, reducing cognitive overload, stimulating the brain and preserving social connection.

Protecting your brain means building a terrain in which it can continue to learn, adapt, recover and remain resilient for as long as possible.

🎧 Go deeper: our episode with William Kadmiry and Anaïs Gautron

In our episode with William Kadmiry and Anaïs Gautron, we explore these levers in detail, and how to integrate them concretely to support cognitive health across life.

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Educational content only. This does not replace medical advice, diagnosis, or care.

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