Creatine: More Than a Muscle Supplement: A closer look at its role in muscle, brain, and overall health, including dosing and safety considerations

Creatine has long been one of the most studied supplements in sports nutrition, primarily recognized for its role in supporting strength and high-intensity exercise performance.  

There is growing interest in its role in recovery, muscle preservation, and broader aspects of health, including its potential relevance in aging and neurologic function. While not all of these applications are fully established, they reflect a shift in how creatine is being viewed from a performance supplement to a compound that supports how the body produces and uses energy, particularly in tissues like muscle and the brain [1]. 

What Creatine Is and How It Works

Creatine is a naturally occurring compound synthesized from amino acids and found primarily in skeletal muscle, with smaller amounts present in the brain and heart. Its primary function is to support the regeneration of ATP, allowing cells to meet short-term, high-energy demands more efficiently [2].

The body is able to produce creatine on its own, primarily in the liver and kidneys, from the amino acids arginine, glycine, and methionine. This internal production helps maintain baseline creatine levels needed for normal function [2].

In addition to what the body makes, creatine is also obtained through diet, with the highest amounts found in animal-based foods such as red meat and fish. However, dietary intake varies widely. Plant-based foods contain little to no creatine, which means individuals following vegetarian or vegan diets rely almost entirely on the body’s own production of creatine [2].

While the body adapts by increasing its own production, studies show that circulating and muscle creatine levels in individuals who follow a vegan or vegetarian diet tend to remain lower compared to those who consume creatine through red meat and fish [2].

Why Skeletal Muscle Is Central to This Conversation

The renewed interest in creatine is closely tied to our expanding view of skeletal muscle and its broader implications on overall health and longevity.

Skeletal muscle functions as a metabolic organ. It plays a key role in glucose uptake, insulin sensitivity, and overall metabolic regulation [3]. Over time, declines in muscle mass and strength (sarcopenia) are associated with reduced overall function, increased risk of falls, and diminished metabolic health [4].

This makes the preservation of muscle an important focus not only for physical performance, but for long-term health. Creatine enters this conversation as a tool that may support that goal when paired with appropriate lifestyle strategies.

What the Research Shows for Muscle Health

The most consistent and well-established evidence for creatine relates to skeletal muscle.

Creatine supplementation has been shown to increase lean muscle mass and improve strength, particularly when combined with resistance training [1]. These effects are not limited to younger individuals. In older adults, creatine has been shown to enhance the benefits of strength training, supporting both muscle mass and physical function [5].

Creatine does not directly build muscle or replace protein intake or exercise. Rather, it supports the body’s ability to produce energy during training, allowing for more effective workouts and, over time, greater improvements in strength and muscle [1].

Creatine and Brain Health: What We Know So Far

Creatine’s role in brain health has become an area of growing interest.

The brain requires a significant amount of energy to function, and creatine helps support the body’s ability to produce and manage that energy [6]. Some research suggests that supplementation may support cognitive performance in situations of increased demand, such as sleep deprivation or mental fatigue. There is also emerging research exploring its role in neurological conditions.

At this stage, the evidence is less consistent than it is for muscle. While the underlying physiology is compelling, findings in healthy populations have been mixed, and consistent improvements in cognitive performance have not been clearly demonstrated [7].

Overall, this is an area of growing interest, but one that is still evolving.

Dosing, Type and Practical Use

Creatine monohydrate remains the most studied and recommended form. A typical maintenance dose is 3 to 5 grams per day [1].

Some individuals choose to begin with a loading phase of approximately 20 grams per day (divided into 5 doses) for 5 to 7 days to more rapidly increase muscle stores, followed by a maintenance dose. This approach is more likely to cause water retention and GI side effects. A consistent daily intake will achieve similar results over time [1].

Creatine Cheat Sheet:

• Creatine monohydrate powder is the most studied form

• 3-5 g per day (may start with 3 g and increase slowly)

• A loading dose of 20 g for 5-7 days is optional

• It can be mixed into water or another cold or slightly warm beverage. Avoid adding to hot liquids like tea or coffee as it degrades.

• It can be taken with or without food, but taking with food containing carbohydrates and protein may aide in absorption and reduce any GI side effects.

• Some research suggests that it is most beneficial to take creatine right before or shortly after a workout, however, daily consistency is more important than timing

Safety and Considerations

Creatine is generally well tolerated in healthy individuals when used at recommended doses [1].

Some individuals may experience mild gastrointestinal discomfort, particularly with higher doses. A small increase in body weight can also occur early on, typically reflecting increased water content within muscle tissue rather than fat gain.

Historically concerns about kidney function have been raised; current evidence does not support adverse effects in healthy individuals using standard doses [1].

As with any supplement, it is important to discuss use with your healthcare provider before starting. When purchasing a creatine supplement look for third-party testing and certifications like Good Manufacturing Practice (GMP) or USP-verified to ensure safety and quality.

We recommend the creatine product through Thorne due to the high quality, purity, and rigorous third-party testing, including NSF Certified for Sport®.

Where Creatine Fits in an Integrative Approach

Creatine is best used as a supportive tool, not a primary intervention.

Its benefits are most meaningful when layered onto foundational health behaviors, including adequate protein intake, resistance training, sleep, and overall metabolic support.

As the conversation around muscle, metabolism, and aging continues to evolve, creatine offers a well-researched option to support these systems. Its strongest role remains in skeletal muscle health, with emerging research continuing to explore its broader applications.

References

Kreider RB, Kalman DS, Antonio J, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation. JISSN. 2017.

Ostojic SM, Forbes SC.Creatine as a conditionally essential nutrient: building the case. Adv Nutr. 2022.

DeFronzo RA, Tripathy D. Skeletal muscle insulin resistance is the primary defect in type 2 diabetes. Diabetes Care. 2009.

Cruz-Jentoft AJ, et al. Sarcopenia: European consensus. Age Ageing. 2010.

Chilibeck PD, et al. Creatine + resistance training meta-analysis. Med Sci Sports Exerc. 2017.

Dolan E, Gualano B, Rawson ES. Beyond muscle: the effects of creatine supplementation on brain creatine, cognitive processing, and traumatic brain injury. Eur J Sport Sci. 2019 Feb;19(1):1-14. doi: 10.1080/17461391.2018.1500644. Epub 2018 Aug 7. PMID: 30086660.

Avgerinos KI, et al.

Creatine and cognition systematic review. Exp Gerontol. 2018.