Crenitrate
Also known as: Creatine, Crenitrate, Creatine monohydrate
Overview
Creatine monohydrate is a naturally occurring nitrogenous organic acid found primarily in skeletal muscle and brain tissue, and obtained from dietary sources like meat and fish. It is widely used as a nutritional supplement and ergogenic aid, primarily to enhance muscle mass and strength in resistance training. Increasingly, it is also studied for its potential cognitive benefits. Creatine supports rapid ATP regeneration via the phosphocreatine system, enhancing energy availability in muscle and brain cells. It is well-researched, with extensive high-quality evidence from randomized controlled trials and meta-analyses supporting its efficacy and safety.
Benefits
Creatine monohydrate offers several evidence-based benefits. For muscle hypertrophy, supplementation combined with resistance training produces a small but statistically significant increase in muscle thickness (0.10–0.16 cm) compared to placebo, with a pooled mean effect size of approximately 0.11. This benefit is more pronounced in younger adults. For cognitive function, evidence suggests beneficial effects on specific domains such as memory, attention, and information processing speed, particularly in populations with lower baseline creatine levels, such as vegetarians. While a meta-analysis found no significant effect on overall cognitive function, individual studies show positive effects in memory and attention. Muscle hypertrophy benefits are typically observed after at least 6 weeks of combined supplementation and resistance training, while cognitive benefits may require longer-term supplementation.
How it works
Creatine primarily functions by replenishing adenosine triphosphate (ATP) stores through the phosphocreatine system. This system rapidly regenerates ATP, the primary energy currency of cells, enhancing energy availability in both muscle and brain cells. By increasing the pool of phosphocreatine, creatine supports high-intensity, short-duration activities and may improve brain energy metabolism, thereby potentially supporting cognitive processes. Creatine monohydrate is well absorbed orally, but its ability to cross the blood-brain barrier is limited, restricting its uptake into the brain.
Side effects
Creatine monohydrate is generally regarded as safe for healthy adults, with a well-established safety profile. Common side effects, occurring in more than 5% of individuals, include minor gastrointestinal discomfort. Uncommon side effects, affecting 1-5% of users, primarily involve weight gain due to water retention. Serious adverse events are rare and have not been reported in high-quality clinical trials. There are no significant reported interactions with common medications. However, caution is advised for individuals with pre-existing kidney disease. Vegetarians may experience more pronounced cognitive benefits due to lower baseline creatine stores, while older adults might see slightly smaller muscle hypertrophy benefits compared to younger individuals.
Dosage
The typical maintenance dosage for creatine monohydrate is 3–5 grams per day. A loading phase of 20 grams per day, divided into 4 doses, for 5-7 days is common to rapidly saturate muscle creatine stores, but it is not strictly necessary for long-term benefits. Long-term supplementation at 3–5 g/day is generally considered optimal. While short-term doses up to 20 g/day are safe, long-term doses above 5 g/day are usually not required. Timing relative to exercise may enhance muscle uptake but is not critical for overall efficacy. Co-ingestion with carbohydrates can improve creatine uptake. Creatine monohydrate is the most studied and effective form. Adequate hydration is important during supplementation.
FAQs
Is creatine safe for long-term use?
Yes, extensive research supports the long-term safety of creatine monohydrate supplementation in healthy adults without adverse effects on kidney or liver function.
Does creatine improve cognition?
Evidence suggests modest benefits in specific cognitive domains like memory and attention, particularly in individuals with lower baseline creatine levels, such as vegetarians.
How quickly do effects appear?
Muscle hypertrophy benefits typically appear after 4–6 weeks of consistent supplementation combined with resistance training. Cognitive effects may require a longer duration of use.
Is a loading phase necessary?
A loading phase (e.g., 20g/day for 5-7 days) can speed up muscle creatine saturation, but it is not mandatory. Consistent daily low-dose supplementation (3-5g/day) will achieve saturation over a longer period.
Does creatine cause kidney damage?
No, numerous studies have shown that creatine supplementation does not cause kidney damage in healthy individuals. However, caution is advised for those with pre-existing kidney conditions.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/39070254/ – This systematic review and meta-analysis by Xu et al. (2024) investigated the effects of creatine supplementation on cognitive function. It found that creatine may improve memory, attention, and processing speed, though it did not show a significant effect on overall cognition. The study highlighted high heterogeneity among included trials and small sample sizes in some studies, but was conducted following PRISMA guidelines.
- https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2024.1424972/full – This article, also by Xu et al. (2024), provides a detailed systematic review and meta-analysis on creatine's impact on cognitive function. It concludes that creatine supplementation can enhance specific cognitive domains like memory and attention, but notes the need for more robust studies to confirm effects on overall cognitive function due to observed heterogeneity.
- https://pubmed.ncbi.nlm.nih.gov/37432300/ – Burke et al. (2023) conducted a systematic review and meta-analysis of 10 randomized controlled trials, demonstrating a small but statistically significant increase in muscle hypertrophy when creatine supplementation is combined with resistance training in healthy adults. The study used imaging-based measures for hypertrophy, lending high quality to its findings, despite a small effect size.
- https://academic.oup.com/nutritionreviews/article/81/4/416/6671817 – Prokopidis et al. (2023) performed a systematic review and meta-analysis focusing on creatine's effects on memory performance. The review found a beneficial effect on memory, with vegetarians showing greater responsiveness. It noted limitations in determining a clear dose-response relationship and the need for more long-term studies, but provided detailed subgroup analyses.