Powering the Aging Brain: Why Energy Is Everything

By Shannon Kasun, Neuroscience Specialist

The brain weighs just about 3 pounds, yet it consumes nearly 20% of the body’s total energy.

That alone tells us something important: the brain is not just another organ. It is an energy-intensive system—constantly processing, filtering, predicting, and responding. Every thought, movement, emotion, and decision is powered by your brain, second-by-second. It is our engine of existence.

From the moment you wake up, your brain is flooded with information. It prioritizes, suppresses, encodes, and reacts—all while maintaining internal balance. This continuous demand is reflected in its disproportionately high energy consumption.

In short: your brain runs on energy. And when energy production declines, function follows.

Aging, Energy, and the Mitochondrial Link

At the center of this conversation are mitochondria—the structures within cells responsible for producing ATP, the body’s primary energy currency. Over time, mitochondrial function declines. In fact, mitochondrial dysfunction is so ubiquitous, it is now recognized as one of the twelve hallmarks of aging.

As mitochondrial efficiency drops, cells produce less energy. In the brain, this has direct consequences: reduced cognitive performance, slower processing speed, and impaired resilience under stress. Some researchers even propose that “Mitochondrial dysfunction may be the primary cause of [Alzheimer’s disease], and is a promising target for new therapeutic strategies” (Ashleigh et al., 2022).

If energy production is compromised, the system begins to fail. So the question becomes: how do we support brain energy metabolism as we age?

Supporting the Brain’s Energy Systems

Two emerging strategies focus directly on improving mitochondrial function and ATP production: photobiomodulation and high-dose creatine.

1. Light as a Biological Signal: Photobiomodulation (PBM)

Photobiomodulation (PBM) is a noninvasive approach that uses red to near-infrared light (approximately 620–1100 nm) applied to the scalp. These wavelengths are able to penetrate the skull and interact directly with brain tissue, influencing cellular function at a fundamental level. One of the primary targets is cytochrome c oxidase, an enzyme within the mitochondria that plays a critical role in the electron transport chain—the final step of ATP production.

When stimulated by light, cytochrome c oxidase becomes more active, leading to increased ATP production and improved mitochondrial efficiency. The result is greater energy availability at the cellular level, supporting overall brain function and cognitive performance.

This mechanism is supported by human data. In one study, participants who received active photobiomodulation prior to completing a card-sorting task—a measure of executive function—performed significantly better than those who received a placebo (Blanco et al., 2017).

2. Fueling the System: High-Dose Creatine

Creatine is best known for its role in muscle performance, but its function in the brain is just as important. At a cellular level, creatine helps regenerate ATP. It acts as a rapid energy buffer, allowing cells to maintain energy output during periods of high demand. This becomes especially relevant under stress—when the brain’s energy requirements increase, such as during aging and sleep deprivation.

Recent research has explored the effects of higher doses of creatine on cognitive performance. In one study, a single high dose (0.35 g/kg) of creatine monohydrate significantly improved cognitive performance and processing speed in sleep-deprived individuals (Gordji-Nejad et al., 2024).

Energy Is the Foundation

Cognition is often framed in terms of networks, neurotransmitters, or behavior. But underneath all of it is something more fundamental: energy.

Every neural signal, every memory, every decision depends on the brain’s ability to produce and manage ATP efficiently. As we age, that system becomes less reliable.

Interventions like photobiomodulation and creatine do not target symptoms—they target the underlying energy systems that support brain function. And in doing so, they point toward a broader principle:

If you want to support the brain, start by supporting its energy.

References 

Ashleigh, Theophania et al. “The role of mitochondrial dysfunction in Alzheimer's disease pathogenesis.” Alzheimer's & dementia : the journal of the Alzheimer's Association vol. 19,1 (2023): 333-342. doi:10.1002/alz.12683

Gordji-Nejad, A., et al. “Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation.” Sci Rep 14, 4937 (2024). https://doi.org/10.1038/s41598-024-54249-9