BDNF: What Is Brain-Derived Neurotrophic Factor and Why It Matters for Brain Health

Every thought you hold, every memory you retrieve, and every new skill you learn depends on your brain's ability to rewire itself. At the molecular level, much of that adaptability traces back to a single protein: brain-derived neurotrophic factor, or BDNF.

For adults over 45, maintaining healthy BDNF levels becomes increasingly relevant. Research suggests that BDNF production naturally declines with age, and this decline may be one of the biological factors underlying age-related changes in memory, processing speed, and cognitive flexibility.¹

This article explains what BDNF is, how it supports brain health, and what evidence-based strategies may help maintain healthy BDNF levels as part of a comprehensive approach to cognitive wellness.

What Is BDNF and What Does It Do in the Brain?

BDNF belongs to a family of proteins called neurotrophins, which regulate the development, maintenance, and function of neurons. It binds to receptors on neuron surfaces (primarily the TrkB receptor) and activates intracellular pathways that promote neuronal health.

Specifically, BDNF supports:

• Neuronal survival — helping existing neurons stay alive and functional
• Synaptic plasticity — strengthening the connections between neurons, which is the biological basis of learning and memory
• Neurogenesis — the formation of new neurons in certain brain regions, particularly the hippocampus, which is central to memory formation²
• Neuroprotection — helping neurons resist damage from oxidative stress and metabolic challenges

The hippocampus and prefrontal cortex — two brain regions critical for memory and executive function — are especially sensitive to BDNF signaling.

How Does BDNF Decline With Age?

BDNF production decreases with age, with measurable declines beginning in midlife.¹ Several factors contribute: reduced gene expression of the BDNF gene, accumulated oxidative stress, metabolic changes including insulin resistance, and physical inactivity which removes one of the most potent natural triggers for BDNF production: exercise.

The hippocampus is particularly vulnerable to age-related reductions in BDNF. Since this region is heavily involved in encoding new memories, lower BDNF levels may help explain why many adults notice changes in their ability to learn new information as they age.

What Lifestyle Factors Support Healthy BDNF Levels?

BDNF is not fixed — its production responds to lifestyle and environmental inputs.

Aerobic exercise is one of the most well-documented BDNF boosters. Studies show that moderate to vigorous exercise increases BDNF levels acutely, and regular exercise is associated with sustained higher baseline BDNF.³

Cognitive engagement — learning new skills, reading, problem-solving — promotes synaptic activity that triggers BDNF release.

Sleep quality matters deeply. BDNF production follows a circadian rhythm, and chronic sleep disruption is linked to lower BDNF levels.

Dietary patterns also influence BDNF. Omega-3 fatty acids, polyphenols from fruits and vegetables, and certain amino acids support healthy BDNF expression.²

Can Nutrition and Supplementation Support BDNF?

BDNF production depends on adequate cellular energy and specific nutrients. Creatine supports ATP recycling, and BDNF expression is energy-dependent — neurons need sufficient ATP to manufacture BDNF. By supporting the brain's energy economy, creatine helps maintain the conditions necessary for healthy BDNF signaling. See: The Ultimate Guide to Brain Energy.

Lion's Mane mushroom has been studied for its ability to stimulate nerve growth factor (NGF), a closely related neurotrophin. Read more: NGF Synthesis and Neurogenesis.

Omega-3 fatty acids (particularly DHA) are integral to neuronal membrane structure and have been shown to upregulate BDNF gene expression in preclinical studies. For a broader overview: Evidence-Based Brain Supplements.

Recognizing When Cognitive Support May Be Needed

While low BDNF is not a diagnosis, reduced BDNF signaling is associated with certain cognitive changes: taking longer to learn new information, feeling mentally fatigued after activities that used to feel effortless, occasional difficulty recalling names or words, and reduced ability to sustain focus during complex tasks.

These experiences can overlap with general mental fatigue and age-related cognitive changes. For a closer look: Brain Fog vs. Mental Fatigue.

Frequently Asked Questions About BDNF

References

1. Erickson, K. I., et al. (2012). The aging hippocampus: Interactions between exercise, environment, and BDNF. The Neuroscientist, 18(1), 82–97.
2. Phillips, C. (2017). Brain-derived neurotrophic factor, depression, and physical activity: Making the neuroplastic connection. Neural Plasticity, 2017, 7260130.
3. Huang, T., et al. (2014). The effects of physical activity and exercise on brain-derived neurotrophic factor in healthy humans: A review. Scandinavian Journal of Medicine & Science in Sports, 24(1), 1–10.

By Lumnira Research Desk / Reviewed by Grady Coleman. This article is for informational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Always consult a qualified healthcare provider before starting any new supplement regimen.