BDNF (Brain-Derived Neurotrophic Factor): “Brain Food”
That Strengthens the Mind and Soul
Over the past several decades, modern neuroscience has
revealed a remarkable fact: the human brain is not a static organ but a highly
dynamic system capable of changing and adapting throughout life. One of the key
factors underlying this remarkable capacity is a protein known as Brain-Derived
Neurotrophic Factor (BDNF). Often described metaphorically as “fertilizer
for the brain,” BDNF plays a vital role in maintaining the health,
connectivity, and functional performance of neurons.
BDNF belongs to a family of proteins known as neurotrophins,
which support the growth, maintenance, differentiation, and survival of
neurons. It is particularly abundant in important brain regions such as the hippocampus,
which is crucial for learning and memory, and the cerebral cortex, which
is involved in information processing, decision-making, and higher cognitive
functions. In this sense, BDNF functions much like an essential nutrient that
helps keep brain cells alive, active, and effectively connected with one
another.
The functions of BDNF are broad and profound. First, it
supports neuronal survival by helping protect nerve cells from damage and
degeneration. Second, BDNF contributes to neurogenesis, the formation of
new neurons, particularly in the hippocampus. Third, it strengthens synapses,
the connections between neurons that form the biological foundation of
learning, memory, and higher-order thinking. When BDNF signaling is inadequate,
the brain may become less capable of adapting to new information and may become
more vulnerable to cognitive dysfunction.
Interestingly, the human body has a natural mechanism for
stimulating BDNF production: physical activity, particularly exercise
performed at moderate-to-high intensity. During challenging exercise, skeletal
muscles work harder and produce lactate as a by-product of energy
metabolism. Lactate, however, is not simply a metabolic waste product.
Increasing evidence indicates that it can also act as a biological signaling
molecule involved in pathways that influence brain function and BDNF expression.
High-intensity exercise, including High-Intensity
Interval Training (HIIT), has been shown in several studies to produce
acute increases in circulating BDNF. HIIT alternates short periods of vigorous
exercise with brief recovery intervals, creating a strong metabolic stimulus
within a relatively short period. Some studies have reported substantial
transient increases in BDNF following such exercise, although the magnitude of
the response varies according to exercise intensity, duration, fitness level,
training status, and the biological characteristics of the individuals involved.
In addition to HIIT, resistance training can also
contribute to beneficial neurobiological adaptations. When skeletal muscles
contract against resistance, they release signaling molecules known as myokines.
These muscle-derived signaling factors participate in communication between
skeletal muscle and other organs, including the brain. Through this
muscle–brain communication, exercise may influence neurotrophic signaling and
support processes associated with cognition, mood, and brain plasticity.
Aerobic exercise, such as
running, cycling, and swimming, also provides important benefits, particularly
when performed at moderate-to-vigorous intensity. Regular aerobic activity
improves cardiovascular fitness and cerebral blood flow and may support
neurotrophic signaling, including BDNF-related pathways. Meanwhile, activities
involving complex motor skills—such as tennis, basketball, dancing, and other
coordination-demanding sports—may provide additional cognitive stimulation
because they require rapid decision-making, spatial awareness, motor
coordination, anticipation, and strategic responses. In this way, exercise can
simultaneously challenge both the body and the brain.
The increase in BDNF associated with physical activity
may have important implications for mental health and cognitive function.
BDNF contributes to neuroplasticity—the brain's ability to reorganize its
neural connections in response to learning, experience, and environmental
demands. This capacity is essential for acquiring new skills, adapting to
changing circumstances, and maintaining cognitive resilience throughout life.
BDNF has also been investigated in relation to stress,
mood regulation, and depression. Chronic stress can negatively affect neural
plasticity and brain function, whereas regular physical activity may help
counteract some of these effects through multiple biological pathways,
including neurotrophic signaling. For this reason, BDNF is sometimes described
in popular literature as a potential “natural antidepressant.” However, it is
important to recognize that BDNF is only one component of a much larger and highly
complex biological network involved in mental health.
The relationship between BDNF and brain fog is
also attracting increasing public interest. Brain fog is not a specific medical
diagnosis but a general term used to describe difficulties with concentration,
mental clarity, memory, or sustained attention. Because BDNF is involved in
synaptic plasticity and cognitive processes, maintaining healthy neurotrophic
signaling may contribute to optimal brain function. Nevertheless, brain fog can
have many causes, including inadequate sleep, chronic stress, poor nutrition,
illness, medication effects, and other factors; therefore, BDNF should not be
regarded as a single explanation for cognitive difficulties.
One of the most interesting aspects of exercise-induced
BDNF responses is that the effect does not necessarily require prolonged
training sessions. Research indicates that even a single session of exercise
can produce a temporary increase in circulating BDNF, particularly when the
exercise is sufficiently vigorous. However, these acute changes are transient.
The more important long-term benefit comes from maintaining a consistent
pattern of physical activity, which may promote cumulative adaptations in brain
health, cardiovascular fitness, metabolic function, and neural plasticity.
Ultimately, the story of BDNF teaches us an important
lesson: brain health is influenced not only by what we think, but also by
how we move. Physical activity is not merely a strategy for maintaining
physical fitness. It is also a form of biological investment in cognitive
resilience, mental well-being, learning capacity, and quality of life.
Making exercise part of a daily or weekly routine,
therefore, should not be viewed merely as an option for improving physical
appearance or athletic performance. It can also be regarded as an investment in
the long-term health of the brain. Behind the sweat, increased heart rate, and
temporary fatigue, the body is sending powerful biological signals to the
brain—supporting neural plasticity, strengthening the networks involved in
learning and memory, and helping maintain psychological resilience.
In this sense, BDNF truly represents a form of “Brain
Food”—not food that we eat, but a biological signal that helps nourish the
brain from within. Every step, every repetition, every sprint, and every
challenging movement may contribute to a healthier dialogue between the muscles
and the brain. By moving the body, we are, in a very real biological sense,
also helping to strengthen the mind and nurture the soul.
References
- Cotman, C.
W., & Berchtold, N. C. (2002). Exercise: A behavioral intervention to
enhance brain health and plasticity. Trends in Neurosciences, 25(6),
295–301.
- Dinoff, A.,
Herrmann, N., Swardfager, W., Liu, C. S., Sherman, C., Chan, S., &
Lanctôt, K. L. (2017). The effect of exercise training on resting
concentrations of peripheral brain-derived neurotrophic factor (BDNF): A
meta-analysis. PLoS ONE, 12(9), e0177474.
- Ferris, L.
T., Williams, J. S., & Shen, C. L. (2007). The effect of acute
exercise on serum brain-derived neurotrophic factor levels. Medicine
& Science in Sports & Exercise, 39(4), 728–734.
- Huang, E. J.,
& Reichardt, L. F. (2001). Neurotrophins: Roles in neuronal
development and function. Annual Review of Neuroscience, 24,
677–736.
- Knaepen, K.,
Goekint, M., Heyman, E. M., & Meeusen, R. (2010).
Neuroplasticity—Exercise-induced response of peripheral brain-derived
neurotrophic factor: A systematic review of experimental studies in human
subjects. Sports Medicine, 40(9), 765–801.
- National
Institutes of Health. (n.d.). Research and publications on brain-derived
neurotrophic factor (BDNF), neuroplasticity, exercise, and brain health. PubMed
and National Center for Biotechnology Information (NCBI).
- Rasmussen,
P., Brassard, P., Adser, H., Pedersen, M. V., Leick, L., Hart, E., Secher,
N. H., Pedersen, B. K., & Pilegaard, H. (2009). Evidence for a release
of brain-derived neurotrophic factor from the brain during exercise. The
Journal of Physiology, 587(20), 4871–4881.
- Vaynman, S.,
Ying, Z., & Gomez-Pinilla, F. (2004). Hippocampal BDNF mediates the
efficacy of exercise on synaptic plasticity and cognition. Neuroscience,
119(3), 815–824.
- Fisher Center
for Alzheimer's Research Foundation. (n.d.). Educational resources on
exercise, brain-derived neurotrophic factor, and cognitive health.
- Journal of
Biomedical Science. (n.d.). Research articles addressing
neurotrophic factors, neurological biomarkers, and brain health.
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