This study asked whether a single 0.2 g/kg dose of creatine could blunt cognitive decline during sleep deprivation. The short answer is yes, at least to some degree: the effects were modest overall, but they showed up in logic, numerical tasks, language-related processing speed, and psychomotor vigilance, with women appearing to benefit more strongly in several measures.

1. Introduction: why creatine matters beyond exercise

Creatine is usually framed as a sports supplement, but recent work points to broader relevance in brain function, neuroprotection, mood, fatigue, and cognition. Earlier research suggested that a higher single dose could help under sleep deprivation, and this paper tests whether a lower dose can still preserve some benefit while improving practicality and safety.

2. Materials and methods: participants and protocol

2.1. Participants

The study enrolled 29 healthy adults, including 17 women and 9 vegetarians, with an average age of 27. Participants avoided caffeine and alcohol before the sessions, followed a controlled sleep schedule, and had no major neurological, psychiatric, or substance-use issues.

2.2. Procedure

This was a randomized, double-blind, crossover study. Participants went through two sleep-deprivation nights, taking creatine on one and placebo on the other, while remaining awake under supervision.

The key measurement points were a baseline test in the evening, creatine or placebo intake at 9 PM, and additional cognitive tests late at night and into the early morning.

2.2.1. Cognitive tasks

The battery included subjective sleepiness and fatigue scales, a psychomotor vigilance task, several memory tasks, and multiple-choice language, logic, and numerical tasks. This gave the researchers a broad view of both reaction-time performance and higher-level reasoning under sleep pressure.

2.3. Statistical analysis

The researchers used linear mixed models and difference-in-differences comparisons to examine how creatine changed the trajectory of decline relative to placebo, while correcting for multiple comparisons.

3. Results: measurable but selective cognitive protection

Sleep deprivation clearly worsened fatigue and several cognitive measures. Creatine did not erase that effect, but it did seem to soften it in a few important places.

3.1. Linear mixed model findings

Under placebo, performance deteriorated across logic, vigilance, memory, and fatigue-related measures. Under creatine, the clearest interaction appeared in logic and one vigilance-variability metric, suggesting a flatter decline curve relative to placebo.

3.2. Difference-in-differences findings

3.2.1. What sleep deprivation did under placebo

With placebo, sleepiness and fatigue rose sharply, while performance in reaction time, logic, and several memory-related tasks worsened over the course of the night. The later the testing point, the more visible the degradation became.

3.2.2. What happened after creatine

Creatine did not stop fatigue from increasing, but some task performance improved relative to baseline, especially in numerical work, language-related speed, and logic-related speed. The effects were directionally positive even when not all single time-point comparisons survived strict statistical correction.

3.2.3. Creatine versus placebo

Compared directly with placebo, creatine improved logic, numerical tasks, language-related processing speed, and variation in vigilance-task reaction times. Women showed especially strong gains in logic, processing speed, and several vigilance metrics, while some vegetarian subgroups also appeared to benefit.

4. Discussion: dose, sex differences, and personalized use

The paper suggests that low-dose creatine can help during sleep deprivation, though less dramatically than earlier high-dose work. The strongest signals appeared in working-memory-adjacent and processing-speed tasks rather than every cognitive domain.

A particularly interesting result is the apparent sex difference: women seemed more responsive than men on several measures. The authors connect this to possible differences in baseline creatine biology, hormone-related variation, and transport dynamics, though they are careful to treat these as hypotheses rather than settled explanations.

5. Conclusion: a practical but partial tool

A single 0.2 g/kg dose of creatine appears safe and may provide a meaningful, if limited, buffer against some of the cognitive costs of sleep deprivation. The paper stops short of treating creatine as a cure-all, but it does make a strong case for more work on dose optimization and subgroup-specific strategies.