As a neuroscience researcher and psychiatrist, I've been treating patients for over two decades. I've found that there are certain daily habits that influence our mental resilience and brain health.

In my new book, "Healing The Modern Brain," I offer ways to strengthen your brain health through tiny, evidence-based lifestyle changes. The first step is to know where you stand.

If you can answer "yes" to all five questions below, you're already implementing the key elements of brain fitness that most Americans currently lack.

1. Did you remember any of your dreams from this week?

Dream recall indicates quality REM sleep — the phase when your brain processes emotions and consolidates memories. When my patients track their sleep, I'm interested in total hours and even more intrigued when they mention vivid dreams.

Why it matters: During sleep, your brain's glymphatic system activates to clear metabolic waste.

Researchers discovered that this waste-clearance system works primarily during sleep, with brain cells creating pathways for cerebrospinal fluid to flow through and clear out toxins that accumulate during wakefulness. This process removes proteins like beta-amyloid that can contribute to cognitive decline.

DON'T MISS: How to start a side hustle to earn extra money

Sleep disruption directly impacts mental health — insomnia nearly doubles the risk of developing depression, according to comprehensive meta-analyses.

2. Have you eaten anchovies, pesto or lentils this past week?

These foods illustrate the idea of nutrient density, and they offer specific nutrients essential for brain function: omega-3 fatty acids (anchovies), folate (basil in pesto) and fiber and B vitamins (lentils).

Why it matters: A landmark study demonstrated that approximately one-third of participants with major depression achieved full remission simply by improving their diet. More recent research shows that diets rich in ultra-processed foods are associated with increased depression risk.

The Mediterranean diet, rich in these brain-supporting foods, significantly reduces inflammation markers associated with depression. Omega-3s specifically help maintain neuronal membrane fluidity and support synapse formation — both critical for learning and emotional regulation.

3. Did you have meaningful interactions with at least three people this past week?

Human connection provides essential neurobiological support for brain health. But the quality of these interactions matters more than quantity.

Why it matters: A comprehensive meta-analysis of 148 studies found that strong social relationships increase survival by approximately 50% — comparable to the effects of quitting smoking.

Positive social interactions trigger oxytocin release, which reduces cortisol levels and inflammatory processes. Even brief social exchanges can improve cognitive performance.

Conversely, social isolation is associated with increased risk for cardiovascular disease and stroke —reflecting how deeply our neurobiological systems depend on human connection.

4. Did you have an adventure outdoors this past week?

Regular nature exposure offers measurable benefits for brain function and mental health, particularly in our increasingly digital world.

Why it matters: Stanford researchers found that a 90-minute walk in nature reduced neural activity in the subgenual prefrontal cortex — an area associated with rumination and depression. Similarly, forest walks were shown to reduce amygdala activity compared to urban environments, indicating a reduced stress response.

Natural environments also expose us to phytoncides — antimicrobial compounds released by trees and plants. These compounds increase natural killer cell activity, enhancing immune function after forest exposure. Your brain benefits from natural settings in ways that indoor environments simply cannot replicate.

5. Did you write in your journal this past week?

Self-reflection through writing provides measurable cognitive and emotional benefits by helping process experiences and clarify thinking.

Why it matters: Meta-analyses have found that expressive writing can improve both physical and psychological health outcomes. Neuroimaging studies reveal that labeling emotions through writing activates the prefrontal cortex while dampening amygdala activity, effectively reducing emotional reactivity.

This process strengthens neural pathways associated with emotional regulation. UCLA researchers found that putting feelings into words — a process called "affect labeling" — diminishes emotional reactivity and helps process difficult experiences, creating measurable changes in brain function.

Challenge your mental health in new ways

These five practices form the foundation of what I call "Mental Fitness," a framework I've developed after years of clinical practice in psychiatry.

By incorporating them into your daily life, you are building biological resilience against modern stressors. Small, consistent changes in how you sleep, eat, connect, experience nature and reflect can transform your mental health by working with your brain's capacity for adaptation and growth.

Dr. Drew Ramsey, MD, is a board-certified psychiatrist, author and leading voice in neuroscience, nutritional psychiatry and integrative mental health. For 20 years, he served as an assistant clinical professor of psychiatry at Columbia University, where he taught and supervised psychotherapy and nutritional psychiatry. His work has been featured by The New York Times, The Wall Street Journal, The Today Show and NPR. His new book is "Healing the Modern Brain: 9 Tenets to Build Mental Fitness and Revitalize Your Mind." 

Want to earn some extra money on the side? Take CNBC's new online course How to Start a Side Hustle to learn tips to get started and strategies for success from top side hustle experts. Sign up today and use coupon code EARLYBIRD for an introductory discount of 30% off $97 (+taxes and fees) through April 1, 2025.