Study Notes on Creatine in Health and Disease
Background Information
Authors: Richard B. Kreider and Jeffery R. Stout
Title: Creatine in Health and Disease
Journal: Nutrients, 2021, 13, 447.
Date of Publication: January 29, 2021
License: Creative Commons Attribution (CC BY) license.
Affiliations:
Texas A&M University, Department of Health & Kinesiology
University of Central Florida, School of Kinesiology and Physical Therapy
Abstract Summary
Creatine has primarily been studied as an ergogenic aid; however, it also provides health benefits.
It plays a critical role in cellular metabolism, particularly during stresses and disease, where its availability can impact metabolic functions.
This review investigates the role of creatine in promoting health and treating chronic diseases, suggesting benefits throughout the lifespan.
Introduction
Creatine Supplementation:
Known as an effective ergogenic aid for athletes.
Promotes anaerobic energy capacity and muscle mass.
Recent research has explored creatine’s potential therapeutic role in various health conditions:
Diabetes
Sarcopenia
Cancer
Cognitive health
Cardiovascular health
Methodology
A systematic review was conducted using PubMed, reviewing a total of 1322 articles related to creatine supplementation. Relevant studies were highlighted to discuss the effects on metabolism, performance, and health.
Metabolic Role of Creatine
**Chemical Composition: **
Creatine (N-aminoiminomethyl-N-methyl glycine): A nitrogen-containing compound derived from amino acids.
**Synthesis: **
Formed from arginine and glycine via arginine glycine amidinotransferase (AGAT) to guanidinoacetate (GAA), followed by methylation by guanidinoacetate N-methyltransferase (GAMT).
GAA is primarily synthesized in the kidney, converted to creatine in the liver.
Endogenous synthesis accounts for about 50% of daily needs for creatine.
Dietary Sources:
Obtained from red meat and fish or via supplements. Vegetarians may have lower levels.
Storage:
Approximately 95% of creatine is stored in muscle (2/3 as phosphocreatine and the rest as free creatine).
Breakdown:
Creatine is broken down into creatinine (1-2% daily) and excreted in urine.
Recommended daily intake of creatine for a healthy adult is 2-4 g/day.
Mechanisms of Action
Energy Production:
Creatine and its phosphagens provide energy through the creatine kinase (CK) and phosphocreatine (PCr) system, replenishing ATP during high-energy demand situations (e.g., intense exercise).
ATP Synthesis:
The degradation of ATP into ADP and inorganic phosphate (Pi) allows creatine sources to facilitate ATP resynthesis.
Role in Oxygen Supply:
Enhances ATP availability when oxygen supply is compromised (ischemia, hypoxia).
Antioxidant Properties:
Reduces reactive oxygen species (ROS) levels, acting as an antioxidant.
General Health Benefits
Proven effects linked to creatine supplementation include:
Increased Muscle Mass and Strength:
Improvements in physical performance of 10-20% on high-intensity tasks (fitness and sports activities).
Enhanced Muscle Recovery and Injury Management:
Has been shown to mitigate risks related to chronic diseases and aid recovery.
Cognitive Function Improvement:
Particularly beneficial in older populations, enhancing mental capacity and coordination.
Organizations such as the International Society of Sports Nutrition endorse creatine as one of the best-supported ergogenic supplements available.
Aging Population Considerations
Sarcopenia
Sarcopenia is characterized by losing muscle mass and strength with age. Creatine supplementation can counteract these effects, particularly when combined with resistance training.
Studies supporting this include:
Brose et al. (2003): Found improvements in muscle mass and strength in older adults after creatine supplementation.
Chrusch et al. (2001) & Candow et al. (2008): Reported gains in muscle mass, strength, and reduced muscle degradation markers.
Cognitive Function
Creatine supplementation can increase brain phosphocreatine levels and mitigate cognitive fatigue.
Evidence from various studies indicates improvements in memory and cognitive performance in older populations.
Glucose Management & Diabetes
Enhances glucose uptake and insulin sensitivity. Studies indicate improvements in HbA1c levels among those with diabetes through supplementation, influencing GLUT-4 transporters positively.
Heart Disease
Plays a pivotal role in myocardial bioenergetics during ischemic conditions. Creatine can facilitate recovery during rehabilitation post-heart failure and improve overall heart health.
Clinical studies suggest adjunctive therapies involving creatine for functional improvements.
Spinal Cord Injury and Rehabilitation
Clinical evidence points towards effective outcomes from creatine in muscle recovery and enhancing rehabilitation for injuries.
Additional Therapeutic Roles
Pregnancy
Limited data suggests creatine could support neural development in fetuses and aid post-birth recovery, though more research is necessary.
Cancer & Anti-inflammatory Effects
Early results show potential antitumor effects of creatine. The accompanying anti-inflammatory benefits may also assist muscle recovery during exhaustive activities.
Immune Response and Fertility
Studies indicate creatine can support immune function, by modulating cytokines and have beneficial effects on sperm function, potentially improving fertility outcomes.
Summary and Conclusions
Overall, creatine supplementation is beneficial in enhancing energy metabolism, supporting cognitive and muscle functions, improving glucose management, and offering protective effects in various medical conditions.
Recommendations for consumption include:
A daily intake of at least 3 g is suggested for general health and maintenance amidst aging.
Possible adjunct therapies in case of specific conditions like neurodegenerative disorders, chronic fatigue, or muscle degradation diseases.
Further research is necessary to explore the full extent and specific applications of creatine in health and various diseases.
Creatine, a nitrogen-containing compound, plays a critical role in cellular metabolism. While primarily recognized as an effective ergogenic aid for athletes, enhancing anaerobic energy capacity and muscle mass, it also offers significant health benefits across the lifespan. Its therapeutic potential is being explored in conditions such as diabetes, sarcopenia, cancer, and for cognitive and cardiovascular health.
Endogenously synthesized and obtained from diet or supplements, 95% of creatine is stored in muscle. It functions by replenishing ATP through the creatine kinase (CK) and phosphocreatine (PCr) system, crucial during high-energy demand. It also aids ATP availability during oxygen scarcity and acts as an antioxidant.
General health benefits include improvements in muscle mass, strength, and physical performance by , enhanced muscle recovery, and improved cognitive function, especially in older adults. Key organizations like the International Society of Sports Nutrition endorse its efficacy.
For aging populations, creatine counteracts sarcopenia (muscle loss) when combined with resistance training and improves cognitive function by increasing brain phosphocreatine. It also enhances glucose uptake, insulin sensitivity, and improves HbA1c levels in diabetes, and supports myocardial bioenergetics post-heart failure. Evidence also suggests benefits in spinal cord injury rehabilitation.
Emerging therapeutic roles indicate potential in supporting fetal neural development during pregnancy, exhibiting antitumor and anti-inflammatory effects, and boosting immune function and fertility.
Overall, creatine supplementation is beneficial for energy metabolism, cognitive and muscle functions, glucose management, and offers protective effects. A daily intake of at least is recommended for general health and as a possible adjunct therapy in specific conditions. Further research is needed to fully understand its applications.