Guanidinoacetate-Creatine Supplementation Improves Functional Performance and Muscle and Brain Bioenergetics in the Elderly: A Pilot Study

Creatine with guanidinoacetic acid improves prefrontal brain oxygenation before, during, and after a cognitive task: A randomized controlled pilot trial

Background: Preliminary studies suggest that creatine and guanidinoacetic acid (GAA) may function as moderate vasodilators, enhancing tissue oxygen saturation. However, the potential effects of this combination on brain oxygenation in humans remain unknown. Aim: The primary objective of this randomized controlled pilot trial was to assess cerebral blood oxygenation indices following a 7-day administration of a mixture containing creatine and GAA in healthy adults. Methods: Nineteen apparently healthy young adults (mean age 21.2 ± 0.4 years; 9 females) were randomly assigned to receive either a mixture (consisting of 2 g of creatine and 2 g of GAA) or a placebo in a crossover design. Oxygen saturation (SpO2) and hemoglobin index (tHb) in the prefrontal cortex were assessed at rest (REST), during meditation that focused on mindful breathing (MED), during a three-component cognitive task (TASK), and during a post-task recovery (REC) before and after 7 days of supplementation. Results: Two-way ANOVA with repeated measures revealed statistically significant differences (treatment vs. time interaction) between interventions for SpO2 during the REST (F = 5.733, P = 0.028), MED (F = 5.897, P = 0.026), and REC phases (F = 6.715, P = 0.018), indicating that the creatine-GAA mixture was more effective than placebo in enhancing oxygen saturation in the prefrontal brain both before, during, and after a cognitive task. Conclusion: These promising findings are of considerable interest for nutritional neuroscience but require validation through well-designed longitudinal trials with larger sample sizes. The study is registered at ClinicalTrials.gov (NCT06371651).

The Impact of Short-Term Supplementation With Guanidinoacetic Acid and Creatine Versus Creatine Alone on Body Composition Indices in Healthy Men and Women: Creatine-Guanidinoacetic Acid Affects Body Composition

The main objective of this pilot study was to compare the effects of short-term supplementation with a mixture containing creatine and guanidinoacetic acid (GAA) versus creatine alone on body composition indices in men and women. Twenty-three apparently healthy young adults (mean age: 21.4 ± 0.6 years; 10 females) were randomly assigned to receive either a mixture (consisting of 2 g of creatine monohydrate and 2 g of GAA) or an equimolar amount of creatine monohydrate in a pretest-posttest control group experimental crossover design. After the intervention period, participants entered a 2-week washout phase to minimize any residual effects of the treatment. Body composition was assessed using a multifrequency bioelectrical impedance analysis at baseline (preadministration) and at the 7-day follow-up (postadministration). A significant interaction effect was found for extracellular mass (p=0.009), with creatine-GAA outperforming creatine in augmenting extracellular mass across the whole sample. In the male subsample, creatine was superior to the mixture in increasing intracellular water (p=0.049), whereas the mixture increased extracellular mass, contrasting with the reduction observed with creatine alone (p=0.008). No significant differences between interventions were reported in the female subsample (p > 0.05), indicating that adding GAA to creatine may produce unique, sex-specific effects on body composition. Further studies are needed to validate our findings across different demographic cohorts and various interventional regimens.

Post-marketing surveilance study of creatine-guanidinoacetic acid safety in healthy adults

A post-marketing surveillance study assessed the adverse events and possible risk of elevated homocysteine levels after the supplementation with creatine-guanidinoacetic acid mixture in apparently healthy adults. The participants were recruited through social media platforms and online discussion boards, with side effects and total plasma homocysteine (T-Hcy) levels evaluated regularly during a supplementation period of 6 months. Thirthy eight individuals (n = 38, 34.2% female) completed the evaluation period and were included in the final analyses. Serious side effects were absent. Two participants (5.3%) reported transitional nausea during the introductory weeks of the supplementation; no participants stopped the treatment. Baseline T-Hcy levels were 11.6 ± 3.1 μmol/L (95% confidence interval [CI], from 10.6 to 12.6). The intervention induced a mild reduction in T-Hcy levels across the monitoring period (p = 0.028), with T-Hcy levels after 1, 2, 3, and 6 months were 10.4 ± 3.0 μmol/L, 10.6 ± 2.9 μmol/L, 10.1 ± 2.7 μmol/L, and 9.3 ± 2.8 μmol/L, respectively. These findings suggest the overall tolerability of creatine-guanidinoacetic mixture in healthy adults, with homocysteine-increasing risk of no concern.

Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials

CONTEXT

From an energy perspective, the brain is very metabolically demanding. It is well documented that creatine plays a key role in brain bioenergetics. There is some evidence that creatine supplementation can augment brain creatine stores, which could increase memory.

OBJECTIVE

A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to determine the effects of creatine supplementation on memory performance in healthy humans.

DATA SOURCES

The literature was searched through the PubMed, Web of Science, Cochrane Library, and Scopus databases from inception until September 2021.

DATA EXTRACTION

Twenty-three eligible RCTs were initially identified. Ten RCTs examining the effect of creatine supplementation compared with placebo on measures of memory in healthy individuals met the inclusion criteria for systematic review, 8 of which were included in the meta-analysis.

DATA ANALYSIS

Overall, creatine supplementation improved measures of memory compared with placebo (standard mean difference [SMD] = 0.29, 95%CI, 0.04-0.53; I2 = 66%; P = 0.02). Subgroup analyses revealed a significant improvement in memory in older adults (66-76 years) (SMD = 0.88; 95%CI, 0.22-1.55; I2 = 83%; P = 0.009) compared with their younger counterparts (11-31 years) (SMD = 0.03; 95%CI, -0.14 to 0.20; I2 = 0%; P = 0.72). Creatine dose (≈ 2.2-20 g/d), duration of intervention (5 days to 24 weeks), sex, or geographical origin did not influence the findings.

CONCLUSION

Creatine supplementation enhanced measures of memory performance in healthy individuals, especially in older adults (66-76 years).

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. 42021281027.

Guanidinoacetic Acid as a Nutritional Adjuvant to Multiple Sclerosis Therapy

Tackling impaired bioenergetics in multiple sclerosis (MS) has been recently recognized as an innovative approach with therapeutic potential. Guanidinoacetic acid (GAA) is an experimental nutrient that plays a significant role in high-energy phosphate metabolism. The preliminary trials suggest beneficial effects of supplemental GAA in MS, with GAA augments biomarkers of brain energy metabolism and improves patient-reported features of the disease. GAA can also impact other metabolic footprints of MS, including demyelination, oxidative stress, and GABA-glutamate imbalance. In this mini-review article, we summarize studies evaluating GAA effectiveness in MS, explore mechanisms of GAA action, and discuss the challenges of using dietary GAA as an element of MS therapy.

Effects of Creatine Supplementation on Brain Function and Health

While the vast majority of research involving creatine supplementation has focused on skeletal muscle, there is a small body of accumulating research that has focused on creatine and the brain. Preliminary studies indicate that creatine supplementation (and guanidinoacetic acid; GAA) has the ability to increase brain creatine content in humans. Furthermore, creatine has shown some promise for attenuating symptoms of concussion, mild traumatic brain injury and depression but its effect on neurodegenerative diseases appears to be lacking. The purpose of this narrative review is to summarize the current body of research pertaining to creatine supplementation on total creatine and phophorylcreatine (PCr) content, explore GAA as an alternative or adjunct to creatine supplementation on brain creatine uptake, assess the impact of creatine on cognition with a focus on sleep deprivation, discuss the effects of creatine supplementation on a variety of neurological and mental health conditions, and outline recent advances on creatine supplementation as a neuroprotective supplement following traumatic brain injury or concussion.

Safety of Dietary Guanidinoacetic Acid: A Villain of a Good Guy?

Guanidinoacetic acid (GAA) is a natural amino acid derivative that is well-recognized for its central role in the biosynthesis of creatine, an essential compound involved in cellular energy metabolism. GAA (also known as glycocyamine or betacyamine) has been investigated as an energy-boosting dietary supplement in humans for more than 70 years. GAA is suggested to effectively increase low levels of tissue creatine and improve clinical features of cardiometabolic and neurological diseases, with GAA often outcompeting traditional bioenergetics agents in maintaining ATP status during stress. This perhaps happens due to a favorable delivery of GAA through specific membrane transporters (such as SLC6A6 and SLC6A13), previously dismissed as un-targetable carriers by other therapeutics, including creatine. The promising effects of dietary GAA might be countered by side-effects and possible toxicity. Animal studies reported neurotoxic and pro-oxidant effects of GAA accumulation, with exogenous GAA also appearing to increase methylation demand and circulating homocysteine, implying a possible metabolic burden of GAA intervention. This mini-review summarizes GAA toxicity evidence in human nutrition and outlines functional GAA safety through benefit-risk assessment and multi-criteria decision analysis.