Creatine may help cognition most when the brain is under strain

A 2018 systematic review of randomized controlled trials found that oral creatine may improve short-term memory and intelligence or reasoning in healthy people [1]. But the evidence was small: six studies and 281 participants. Results were mixed for long-term memory, attention, executive function, reaction time, word fluency, response inhibition, and mental fatigue [1]. The strongest negative result comes from healthy young adults. In a 6-week randomized trial, creatine did not significantly improve processing speed, episodic memory, or attention, and did not clearly change prefrontal cortex activation, which is activity in a brain region involved in planning and attention [2]. This fits the review finding that young people often show little or no cognitive change [1]. Older or metabolically stressed groups may be more relevant. In overweight women over 60, higher dietary creatine intake correlated with better performance on a task measuring selective attention and inhibition, especially when the task required resisting distracting information [3]. This was observational, so it cannot prove creatine caused the difference. One double-blind placebo-controlled study of creatine ethyl ester reported improvements on several cognitive measures, but the authors said the findings need replication and better objective checks of compliance [4]. Animal and cell studies also suggest creatine can protect brain function under inflammatory, ischemic, or toxic stress, but those findings do not directly prove benefits in healthy humans [8], [12], [15].

Creatine helps cells buffer and move energy. The brain has high and changing energy demands, and creatine is transported through the blood to tissues including the brain [9]. That is why researchers think it might matter more when brain energy supply is under pressure, such as aging, stress, disease, inflammation, or low dietary intake [1], [3]. In cell and animal models, creatine and phosphocreatine appear to protect neurons partly by supporting high-energy phosphate stores, which are molecules cells use to rapidly maintain energy availability [12]. A rat model of mild cognitive impairment found that creatine improved LPS-induced learning and recognition memory deficits and increased markers linked to synaptic plasticity, meaning the brain’s ability to strengthen or remodel connections between neurons [15]. Other mechanistic work points toward mitochondria, the cell structures that produce usable energy. In a cerebral ischemia model, creatine was linked to reduced mitochondrial damage and neuronal apoptosis, which is programmed cell death [8]. Reviews also connect creatine with brain energy metabolism, mitochondrial function, neuroprotection, and possibly hippocampal neurogenesis, the formation of new neurons in a memory-related brain region [7], [13].

The human cognition evidence is still limited. The main systematic review included only six randomized trials and 281 people [1]. Some studies tested healthy young adults, who may already have enough brain creatine or enough energy capacity to see little benefit [1], [2]. Several included papers are not direct evidence that creatine supplementation improves cognition in healthy humans. Some are observational, some are reviews, and several use animal, cell, or disease models [3], [8], [12], [13], [15]. The results should not be stretched into a claim that creatine prevents dementia or broadly boosts brain performance. The evidence also does not settle who benefits most. Vegetarians responded better than meat-eaters on memory tasks in the systematic review, but not across other cognitive domains [1]. Older adults, people under cognitive stress, and people with low dietary creatine are plausible groups to study, but the abstracts do not provide enough proof for firm guidance.