# Grow New Brain Cells at Any Age

Published March 2026 • 5 min read
Tweet Share

### Key Takeaways

- BDNF (brain-derived neurotrophic factor) is essential for learning and memory
- Exercise increases BDNF levels by 200-300% acutely
- Low BDNF is found in depression, Alzheimer's, and cognitive decline
- Fasting, social connection, and novel experiences also boost BDNF

Your brain can grow new neurons throughout life — a process called neurogenesis. The molecule that makes this possible is BDNF (brain-derived neurotrophic factor), often called 'Miracle-Gro for the brain.' BDNF supports existing neurons, encourages new neural connections, and is essential for learning and memory. The problem? BDNF declines with age, stress, and sedentary living.

## What BDNF Does

BDNF is a protein that binds to TrkB receptors on neurons, triggering signalling cascades that promote synaptic plasticity (the ability of neural connections to strengthen or weaken in response to experience), neurogenesis (growth of new neurons, primarily in the hippocampus), and neuroprotection (shielding existing neurons from damage).

In practical terms, BDNF determines how well you learn, how effectively you form memories, and how resilient your brain is to stress and ageing. High BDNF levels are associated with better cognitive performance, resistance to depression, and protection against neurodegenerative disease. Low levels are consistently found in Alzheimer's, Parkinson's, depression, and age-related cognitive decline.

## What Depletes BDNF

Chronic stress is the biggest BDNF suppressor — cortisol directly inhibits BDNF expression in the hippocampus, which partly explains why chronic stress impairs memory and increases depression risk. Sedentary behaviour, poor sleep, social isolation, and a diet high in sugar and processed food all reduce BDNF levels.

Ageing itself reduces BDNF production, creating a vulnerability window where the brain's repair capacity declines just as accumulated damage increases. This is why maintaining BDNF levels through lifestyle becomes increasingly important with age — it's one of the key mechanisms determining whether you age with cognitive vitality or decline.

## How to Boost BDNF

Aerobic exercise is by far the most potent BDNF booster — a single session can increase levels by 200-300%. The effect is dose-dependent: higher intensity and longer duration produce larger increases. Regular exercise (4+ times weekly) raises baseline BDNF levels, not just acute spikes. Both running and cycling are well-studied, but any sustained aerobic activity works.

Intermittent fasting increases BDNF through mild metabolic stress that triggers protective pathways. Novel experiences and learning new skills (especially complex motor skills like dance, martial arts, or musical instruments) stimulate BDNF in the areas of the brain engaged by the activity. Social connection, adequate sleep, sunlight exposure, and diets rich in omega-3 fatty acids and polyphenols all support BDNF production.

#### Who Is This For?

Anyone interested in evidence-based longevity strategies, health optimisation, and understanding the latest research on ageing and healthspan.

#### Consult Your Doctor If...

You are pregnant, breastfeeding, taking prescription medications, or have a pre-existing medical condition. This content is educational and does not replace professional medical advice.

### Go Deeper

Ready to learn more? These guides break it all down:

Top 8 Compounds Deep Dive Best Longevity Stack Best Anti-Aging Compared Take the Longevity Quiz

### Get Longevity Insights Weekly

Join thousands getting science-backed health tips every week.

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before starting any new supplement or making changes to your health regimen.

#### Sources & References

1. Nature Reviews Neuroscience - BDNF and Synaptic Plasticity
2. Trends in Neurosciences - Exercise and Brain-Derived Neurotrophic Factor
3. Molecular Psychiatry - BDNF in Depression and Neurodegeneration
4. Neurobiology of Aging - BDNF Decline and Cognitive Ageing