Creatine, Ketones, and Sleep: What Really Supports Brain Energy?

Creatine and ketones both supply the brain with backup fuel during high-energy demand, while sleep determines whether that energy system can recover. Research shows creatine offsets sleep-deprivation-related cognitive decline, ketones fuel an aging brain more efficiently than glucose, and specific compounds support the sleep stage where repair happens.

Key Takeaways

• Creatine offsets brain fog caused by poor sleep
• Ketones give an aging brain a backup fuel source
• Sulforaphane supports the brain's own antioxidant defense system
• Glycine and 5-HTP help you fall into deeper sleep

What Makes the Brain So Energy-Hungry?

The brain makes up about 2% of body weight but consumes roughly 20% of the body's energy at rest. Neurons fire constantly, and each signal costs ATP — the cell's energy currency.

When energy production dips, even briefly, the effects show up as brain fog, slower processing, and difficulty holding a thought. This is why sleep loss, blood sugar swings, and aging all register in the brain before they show up anywhere else.

Three separate levers affect this system: how much fuel is available (creatine, ketones), how well cells defend themselves from the byproducts of that fuel use (sulforaphane, NRF2), and whether the brain gets the downtime it needs to reset (sleep chemistry).

How Does Creatine Support Brain Energy?

Creatine works by regenerating ATP faster than the brain can otherwise produce it, through a stored reserve called phosphocreatine. Neurons rely on the same system that muscle cells use during a sprint.

A 2024 systematic review and meta-analysis in Frontiers in Nutrition, covering 16 randomized controlled trials and nearly 500 participants aged 20 to 76, found that creatine monohydrate supplementation produced measurable improvements in specific cognitive domains, including memory. [1]

An earlier double-blind, placebo-controlled crossover trial found that five weeks of creatine supplementation improved working memory and intelligence test scores in healthy adults. [2] The effect size was largest in vegetarians, who typically start with lower baseline creatine stores from diet alone.

Can Creatine Offset the Cognitive Cost of a Bad Night's Sleep?

Yes — a 2024 study in Scientific Reports found that a single high dose of creatine partially reversed the cognitive decline caused by sleep deprivation. Researchers kept 15 adults awake overnight and measured both brain metabolism and cognitive performance.

Sleep deprivation depletes the brain's high-energy phosphate reserves — the same reserves creatine replenishes. In the study, a single dose of creatine measurably increased those reserves and improved processing speed and short-term memory within three to four hours. [3]

This does not make creatine a substitute for sleep. It makes it a documented way to blunt some of the cognitive cost of sleep loss when a full night isn't possible.

What Are Ketones, and Why Can the Brain Run on Them So Well?

Ketones are an alternative fuel the liver produces when glucose is scarce, and the brain can use them almost as efficiently as glucose — sometimes more so. Neurons contain the transporters needed to pull ketones directly from the blood.

This matters more with age. Brain glucose uptake declines as part of normal aging, even before any diagnosable cognitive change appears. Ketone uptake in the aging brain does not show the same decline. [4]

A 2021 review in the British Journal of Nutrition described this gap as a rationale for "brain energy rescue" — using ketones to bridge the fuel shortfall that glucose alone increasingly can't cover as the brain ages. [4] This is the same logic behind liquid exogenous ketone products: raising circulating ketones without requiring a strict low-carbohydrate diet.

Ketones aren't just a backup fuel source, either. Beyond supplying energy, ketone bodies like beta-hydroxybutyrate act as signaling molecules — influencing blood flow to the brain and supporting production of brain-derived neurotrophic factor (BDNF), a protein involved in maintaining healthy neurons over time. [4]

Where Does Sulforaphane Fit Into Brain Energy?

Sulforaphane supports brain energy indirectly, by protecting the mitochondria that produce it. Mitochondria generate ATP, but that process also generates oxidative byproducts — and neurons are especially vulnerable to that damage because they don't regenerate easily.

Sulforaphane activates NRF2, the transcription factor that switches on the body's own antioxidant enzyme systems — including glutathione production, one of the cell's primary defenses against that oxidative load. [6]

Mara Labs' own research illustrates how directly this happens. In HepG2 liver cell testing, BrocElite® Plus increased glutathione production 120% over baseline within 24 hours — 34% higher than the only other stabilized sulforaphane product tested. The glucoraphanin-based comparator did not show a statistically significant induction.

In follow-up testing in human buccal cells, BrocElite® Plus directly induced NRF2 in vivo, as confirmed by immunofluorescence. The unstabilized comparator product did not. [7]

A separate internal study found that a single 10mg serving of BrocElite reduced the inflammatory marker IL-6 by 28% within 24 hours, measured by urine ELISA in six participants. [7] Chronic low-grade inflammation is one of the upstream drivers of the oxidative stress that impairs neuron function over time.

In a 12-week randomized controlled trial published in Frontiers in Aging Neuroscience, 144 older adults who took a sulforaphane supplement showed measurable improvements in processing speed and mood compared to placebo. [5] Separately, animal research has found that sulforaphane supports mitochondrial function directly in brain tissue. [6]

Dr. John Gildea, PhD, Co-Founder and Chief Science Officer at Mara Labs, has described this gut-brain connection directly: "In our lab work, we've found that sulforaphane has significant effects on tightening tight junctions, the actual cellular lining of the gut, which keeps toxins from entering the system in the first place."

Why None of This Works Without Sleep?

Sleep is when the brain clears metabolic waste that accumulates during waking hours, through a drainage system called the glymphatic system. This clearance process ramps up during deep sleep, specifically when brain cells shrink slightly and allow cerebrospinal fluid to flow more freely through surrounding tissue.

Creatine, ketones, and NRF2 support can all improve how efficiently the brain uses energy — but none of them replace this clearance step. A brain that produces energy well but never clears its own metabolic waste is still running at a deficit.

Poor sleep also blunts the very systems this article covers. Sleep deprivation depletes phosphocreatine stores, which creatine has to work overtime to restore in the first place. [3] Supporting sleep quality directly is what makes everything upstream of it more effective, not less necessary.

What's In SleepElite, and Why?

SleepElite® was formulated around serotonin precursors rather than melatonin, so the body produces its own melatonin instead of receiving it pre-made.

The reasoning: sleep quality depends on several separate systems — hormone production, stress regulation, and cellular antioxidant capacity among them — and a single-ingredient approach only addresses one.

Should You Add Glycine to a Sleep Stack?

Glycine is worth considering as an addition, based on two randomized controlled trials that used a 3-gram dose taken before bedtime. Glycine is an inhibitory amino acid that reduces core body temperature — one of the body's natural signals for sleep onset.

A 2007 study measured this using polysomnography (an overnight sleep study) and found that glycine improved sleep efficiency, shortened the time to reach both sleep onset and deep sleep, and reduced next-day sleepiness. [8]

A separate randomized trial tested glycine specifically under sleep-restricted conditions and found it improved next-day psychomotor vigilance test performance, even when total sleep time was reduced by 25%. [9]

For someone already taking SleepElite in the evening, adding 3 grams of glycine at the same time is a research-backed way to build out that stack — targeting the temperature-drop mechanism that 5-HTP and melatonin production don't directly address.

Frequently Asked Questions

Does creatine help the brain, or is it just for muscle?
Both. Creatine regenerates ATP in neurons the same way it does in muscle cells, and multiple randomized controlled trials have found measurable cognitive benefits, particularly for memory. [1][2]

How much creatine is typically studied for brain benefits?
Doses vary by study, from a single high dose of 0.35g per kilogram of body weight in acute sleep-deprivation research to smaller daily doses over several weeks in longer-term cognition trials. [2][3]

Do liquid ketones reach the brain?
Yes. Ketones cross into the brain through dedicated transporters and can be used as fuel almost as readily as glucose, which is part of why ketone uptake doesn't decline with age the way glucose uptake does. [4]

Why doesn't SleepElite contain melatonin?
SleepElite is formulated around 5-HTP and L-tryptophan, precursors the body uses to produce its own melatonin, rather than supplying melatonin directly.

Is 3 grams of glycine a lot to add to a sleep routine?
No — 3 grams is the dose used in the published research on glycine and sleep quality, and it's considered a well-tolerated, non-sedating dose in the studies reviewed here. [8][9]

Can you take creatine and BrocElite together?
Yes. Creatine addresses cellular energy supply while sulforaphane addresses oxidative stress and mitochondrial protection — the two work on different parts of the same energy system rather than overlapping.

Sources

[1] Xu, C., Bi, S., Zhang, W., Luo, L. "The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis." Frontiers in Nutrition, 2024. https://doi.org/10.3389/fnut.2024.1424972

[2] Rae, C., Digney, A.L., McEwan, S.R., Bates, T.C. "Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial." Proceedings of the Royal Society B, 2003. https://doi.org/10.1098/rspb.2003.2492

[3] Gordji-Nejad, A., et al. "Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation." Scientific Reports, 2024. https://doi.org/10.1038/s41598-024-54249-9

[4] Cunnane, S.C., et al. "Ketones: potential to achieve brain energy rescue and sustain cognitive health during ageing." British Journal of Nutrition, 2021. https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/ketones-potential-to-achieve-brain-energy-rescue-and-sustain-cognitive-health-during-ageing/530E99074AF8C90AB5AA3AFFFF7966D8

[5] Nouchi, R., et al. "Effects of Sulforaphane Intake on Processing Speed and Negative Moods in Healthy Older Adults." Frontiers in Aging Neuroscience, 2022. https://doi.org/10.3389/fnagi.2022.929628

[6] Jardim, F.R., et al. "Effects of sulforaphane on brain mitochondria: mechanistic view and future directions." Journal of Zhejiang University Science B, 2020. https://doi.org/10.1631/jzus.B1900614

[7] Mara Labs internal research. "Nrf-2 Induction and Inflammatory Marker (IL-6) White Papers." 2023. Internal HepG2 cell, buccal cell, and urine ELISA testing.

[8] Yamadera, W., et al. "Glycine ingestion improves subjective sleep quality in human volunteers, correlating with polysomnographic changes." Sleep and Biological Rhythms, 2007. https://doi.org/10.1111/j.1479-8425.2007.00262.x

[9] Bannai, M., Kawai, N., Ono, K., Nakahara, K., Murakami, N. "The Effects of Glycine on Subjective Daytime Performance in Partially Sleep-Restricted Healthy Volunteers." Frontiers in Neurology, 2012. https://doi.org/10.3389/fneur.2012.00061

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Written by David Roberts, MPH, Co-Founder, Mara Labs