The brain accounts for only about 2% of the body’s weight, yet it consumes roughly 20% of the body’s total energy.1 That constant demand exists because the brain can’t store much fuel — meaning it must produce energy continuously and efficiently to support every mental function, such as forming memories, keeping focus, regulating mood, processing emotions, making decisions, and responding to stress.
How the brain produces, uses, and maintains fuel is known as brain energy metabolism. Not only is it essential for day-to-day function, but it’s also crucial for long-term brain health as it directly influences neuronal plasticity (your brain’s ability to adapt, change, and reorganize itself) and the brain’s overall resilience as we age.2
In this article, we take a closer look at what brain energy really is and what happens when levels run low. We also cover supportive nutritional and lifestyle habits and discuss creatine’s role as a top emerging supplement for brain energy.
What is Brain Energy and How Does it Work?
Nearly all of the brain’s usable energy comes from adenosine triphosphate (ATP), a molecule produced inside neurons and glial cells. Because the brain uses ATP at an exceptionally fast rate, these cells must continuously generate it to keep essential processes running. When ATP production falls short of demand, these essential processes may become less efficient — and research shows that lower ATP availability is associated with poorer cognitive performance.3
The brain produces ATP through several interconnected metabolic pathways:4
- Glycolysis: Breaks down glucose quickly to make small amounts of ATP.
- Oxidative phosphorylation: Occurs inside mitochondria, producing the majority of brain ATP.
- Phosphocreatine system: Acts as a backup system that rapidly regenerates ATP during moments of high demand.
Together, these systems allow the brain to respond to both everyday cognitive tasks and periods of intense mental work, but they rely on efficiency, which naturally changes with age. Mitochondria become less flexible, oxidative stress increases, and the brain’s ability to generate ATP declines, contributing to slower processing, more mental fatigue, and reduced cognitive resilience.5
What Fuels the Brain? The Role of Glucose, Ketones, and Lactate
Glucose is the brain’s primary energy source, especially for memory formation, focus, and the rapid firing of neurons. But glucose isn’t the only fuel — the brain uses several forms of energy, each with unique advantages and roles.6
When glucose availability is low or metabolism becomes less efficient, the brain shifts into metabolic flexibility. Ketones serve as an alternative energy source, supporting mitochondrial energy production during fasting, low-carbohydrate diets, or periods of impaired glucose uptake.6
Lactate, once considered a metabolic by-product, is now understood as an important brain fuel and signaling molecule. It supports neuroplasticity, improves stress responses, and plays a role in mood regulation.7 During exercise or higher demand, the brain can rely on lactate as an additional fuel source to maintain performance.
These processes can't properly function without adequate oxygen and healthy blood flow, which are essential for mitochondrial ATP production. Anything that improves blood flow, such as regular movement, high quality sleep, and stress management, can support the brain’s energy production. Nutrition and overall metabolic health also determine how effectively the brain can access and use its fuel sources. A well-supported metabolism ultimately strengthens the brain’s energy capacity and may help protect against age-related cognitive decline.8
How Low Brain Energy May Affect Your Cognitive Health
When the brain lacks adequate or efficient energy, cognitive performance slips quickly. Because neurons can’t store much fuel, any disruption — whether due to stress, insufficient sleep, aging mitochondria, gaps in nutrition, or poor glucose metabolism — can show up as changes in how we think or feel.
Common signs of low brain energy include:9
- Brain fog
- Mental fatigue
- Forgetfulness
- Difficulty focusing
- Headaches
- Trouble with problem-solving
- Light and noise sensitivity
- Poor stress tolerance
- Emotional instability
When the brain struggles to produce or use energy efficiently, chronic metabolic dysfunction can develop, which is linked to inflammation, oxidative stress, and accelerated brain aging.10 Research shows that energy deficits are among the earliest detectable changes in cognitive decline, long before structural degeneration is measurable.10 In many cases, early brain aging appears more metabolic than structural, meaning it may be responsive to nutrition, lifestyle, and targeted supplementation.11
How to Boost Brain Energy Through Nutrition and Lifestyle Strategies
Brain metabolism, like all aspects of cognitive health, is greatly influenced by our daily choices. Notably, these habits are crucial for maintaining sufficient brain fuel:
Exercise and Brain Health
Regular physical activity is one of the strongest metabolic supports. Exercise increases glucose delivery, improves blood flow, strengthens mitochondrial function, and raises lactate availability — providing the brain with more flexible fuel options.12
- Boost brain energy today with a brisk walk, cycle session, some light strength training, or a short home workout. Even modest movement can make a meaningful shift in energy metabolism.
Stress Management for Mental Clarity
Stress has a hand in everything — especially in depleting the brain’s energy! Chronic stress elevates inflammatory signaling and disrupts mitochondrial function, forcing the brain to work harder to produce the same amount of ATP.13
- Maintain metabolic stability and promote clarity by practicing simple breathing techniques (such as the 4-7-8 method), scheduling downtime, and setting boundaries around work and other stressors. Remember, prioritizing your brain health is key to healthy living.
Sleep and Cognition
Unsurprisingly, the body’s natural time to recharge is also crucial for replenishing your brain’s battery. Sleep restores energy balance by clearing metabolic waste products and assisting in glucose regulation.14
- Refresh your body and brain with small nightly improvements. Try going to bed 30 minutes earlier, establishing a relaxing sleep routine, or limiting nighttime screen use for a clear mind in the morning.
Nutrients for Cognitive Function
Food is fuel — and quality matters. The Mediterranean and MIND diets support optimal brain energy by providing antioxidants, omega-3 fatty acids, polyphenols, B vitamins, magnesium, and other micronutrients vital to ATP production. A 2024 study shows that following the Mediterranean diet for brain health can improve mitochondrial efficiency and restore ATP-linked energy production, reinforcing the idea that nutrition directly supports the body’s underlying energy systems.15
- Including foods like high quality extra virgin olive oil, fatty fish, leafy greens, legumes, berries, nuts, seeds, and whole grains in your diet provides the raw materials the brain uses to generate essential energy.
To find more habits and science-driven strategies to help you establish more consistent energy levels, and lasting brain health, download our FREE 19-page e-guide below, which includes 10 Proven Actions for a Stronger Brain.
How RELEVATE Helps Address Nutrient Gaps and Cognitive Aging
RELEVATE is formulated to help fill common nutrient gaps where our diets may be lacking. It assists in maintaining metabolic resilience through its diverse nutrient blend, including vitamins, minerals, and antioxidants linked to mitochondrial function, inflammation regulation, and vascular health. RELEVATE aligns with the benefits of the Mediterranean and MIND diets, supporting long-term energy pathways crucial for healthy cognitive aging. In fact, nearly ½ of RELEVATE users report an improvement in their energy levels.16
Creatine for Brain Energy
Creatine has long been known for its muscle-building benefits, but studies are now exploring its exciting potential for cognitive health.
It plays a central role in the phosphocreatine system, in which ATP rapidly regenerates during periods of high demand.17 This becomes especially important for memory support, executive function, and any situation where the brain is under high demand — including stress, sleep loss, and intense mental workload.18
Creatine levels naturally decline with age, which may contribute to slower ATP recovery and reduced mental endurance.19 Research shows that older adults, who commonly have lower baseline levels, experience notable improvements in memory, cognitive performance, and mental fatigue with supplementation.20
Emerging research in creatine for cognition continues to highlight its role in brain energy metabolism. Studies suggest it can enhance cognitive performance during high-demand tasks, support mitochondrial efficiency, and encourage neuroprotection by stabilizing cellular energy during metabolic stress.17,18 By strengthening rapid ATP regeneration and broader metabolic resilience, creatine helps bridge everyday mental performance with longer-term brain support.
For midlife adults, seniors, individuals with lower dietary intake, or anyone noticing more mental fatigue than usual, creatine provides an accessible way to support daily cognitive performance. We have some more exciting news about creatine coming to you soon.
Preventing Energy Deficits and Cognitive Decline Through Better Brain Energy
Brain energy is the foundation of how we think, feel, and function. When ATP production is sufficient, the brain can support memory, mood, focus, and stress resilience — strong indications of cognitive health. As we age, preserving that energy becomes increasingly important, and daily choices such as nutrition, movement, stress management, and sleep are key to maintaining healthy brain metabolism.
In addition to these foundational habits, targeted support can make a meaningful difference. Creatine is emerging as a powerful aid in sustaining rapid ATP production and protecting the brain during periods of higher demand. As research continues to expand, creatine’s role in cognitive support and healthy aging promises to become an even more exciting area of discovery.
References:
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