Creatine is one of the most studied supplements in sports. This guide covers how it works, dosing protocols, timing, and what the research actually shows.
Creatine often comes up in conversations among teammates, coaches, and in the gym. People mention gains, raise questions about kidney function or hair loss, and share a variety of opinions. However, the science supporting creatine is well established and grounded in decades of research, making it one of the most thoroughly studied supplements.
Creatine is a compound naturally produced by the body. It is stored in muscles and plays a crucial role in regenerating cellular energy. Decades of research across thousands of participants support its benefits. The International Society of Sports Nutrition identifies creatine monohydrate as the most effective supplement for increasing high-intensity exercise capacity and lean body mass during training. This conclusion is based on extensive scientific evidence.
What Creatine Is and How It Works in Your Body
Creatine is a naturally occurring non-protein compound synthesized primarily in the liver. The body produces about 1-2 grams per day from amino acids such as arginine, glycine, and methionine. Dietary sources include red meat and fish.
About 95% of total creatine and phosphocreatine stores are in skeletal muscle, with the remainder in blood, brain, testes, and other tissues. This distribution helps explain the effects of supplementation on both physical and cognitive functions.
The Phosphocreatine Energy System
Adenosine triphosphate is the primary energy source for muscle contraction. Muscles store only small amounts of ATP, sufficient for a few seconds of maximal effort.
This is where phosphocreatine comes into play. Phosphocreatine is a phosphorylated form of creatine that acts as a rapidly mobilizable reserve of high-energy phosphates. During intense muscular effort, phosphocreatine donates its phosphate group, converting adenosine diphosphate back to adenosine triphosphate. This process happens anaerobically and sustains maximal effort for approximately 5-8 seconds.
Supplementing with creatine increases phosphocreatine stores. Typical muscle creatine content is approximately 120 millimoles per kilogram of dry muscle mass, but supplementation can raise this to 160 millimoles per kilogram. Increased phosphocreatine supports greater ATP regeneration during high-intensity activity, allowing for more repetitions, higher power output, and improved recovery.
Natural Creatine Depletion and Daily Requirements
The body degrades about 1-2% of intramuscular creatine daily.
Average maintenance requires about 1-3 grams of creatine per day from both endogenous synthesis and dietary intake.
Athletes with greater muscle mass or who engage in frequent high-intensity training may require more to maintain optimal stores.
Creatine Supplementation Protocols
Research supports two primary approaches to creatine supplementation. The choice depends on how quickly muscle saturation is desired and tolerance for potential side effects.
The Loading Protocol
Take 20-25 grams of creatine monohydrate per day for 5-7 days.
Divide the daily dose into 4-5 servings of 5 grams each.
Alternatively, calculate the dose as 0.3 g/kg/day (for a 70-kg athlete, about 21 g/day).
After loading, transition to a maintenance dose of 3-5 grams per day to sustain elevated creatine stores.
Loading saturates muscles within a week; performance benefits can appear quickly.
Some people may experience gastrointestinal discomfort, bloating, or water retention at higher doses.
The Low-Dose Daily Protocol
Daily intake of 3-5 grams of creatine monohydrate (or 0.1 grams per kilogram of body weight) is adequate without loading.
Full muscle saturation typically occurs over 2-4 weeks of consistent supplementation.
A daily intake of 3-5 grams increases creatine stores over time, with fewer side effects and no need for loading.
Strength and endurance improvements typically appear within 1-2 weeks as muscle creatine stores approach saturation.
| Protocol | Daily Dose | Duration | Time to Saturation | Best For |
|---|---|---|---|---|
| Loading Phase | 20-25g (4-5 servings of 5g) | 5-7 days | 5-7 days | Athletes who want rapid results |
| Loading by Body Mass | 0.3g per kg body mass | 5-7 days | 5-7 days | Precise dosing based on size |
| Maintenance (post-loading) | 3-5g per day | Ongoing | Already saturated | Maintaining elevated stores |
| Low-Dose Daily | 3-5g per day | Ongoing | 2-4 weeks | Gradual saturation, fewer side effects |
| Low-Dose by Body Mass | 0.1g per kg body mass | Ongoing | 2-4 weeks | Precise dosing without loading |
When to Take Creatine
Research is ongoing on the optimal timing of creatine intake. Some studies report greater benefits when creatine is consumed after exercise, but findings are mixed. One study found that post-workout creatine intake led to better body composition and greater strength gains than pre-workout intake. Plasma creatine levels do not necessarily correlate with increased blood flow during exercise, which may explain these results.
Consistency is more important than timing. Taking creatine before or after your workout is preferable to taking it several hours before or after training. The key factor is maintaining a daily intake to keep muscles adequately nourished.
Enhancing Creatine Absorption
Consuming creatine with carbohydrates and protein increases retention by about 25%.
This effect is likely related to increased insulin secretion.
The Australian Institute of Sport recommends taking creatine with a meal containing 50 grams of protein and 50 grams of carbohydrates for optimal absorption.
Taking creatine with a post-workout meal containing protein and carbohydrates can support better absorption.
Forms of Creatine: What the Evidence Says
Creatine is available in several forms, including creatine hydrochloride, buffered creatine, and creatine ethyl ester. Marketing claims often position these alternatives as better absorbed or more effective than creatine monohydrate.
Research consistently supports creatine monohydrate as the optimal choice. It is the most extensively studied form, and no alternative has demonstrated superior results in controlled trials. Creatine monohydrate is also typically the most affordable option.
Choose creatine products with third-party certifications, such as NSF Certified for Sport or Informed Choice.
These certifications help ensure product purity and safety.
Safety Profile of Creatine Supplementation
Creatine has a well-established safety record. The International Society of Sports Nutrition reports no scientific evidence of harm from short- or long-term use of creatine monohydrate in otherwise healthy individuals.
Supplementation with up to 30 grams per day for 5 years is safe and well-tolerated in healthy individuals.
Lower doses of 4-5 grams daily for up to 18 months, and up to 10 grams daily for 5 years, have also been safely used in long-term research.
Creatine and Kidney Function
Concerns about kidney damage are not supported by current evidence in healthy individuals. Randomized controlled trials have not found adverse effects of creatine supplementation on kidney function in these populations.
A 2025 systematic review and meta-analysis found creatine safe for kidney function in healthy persons and various clinical populations when used within standard dosing protocols. The International Society of Sports Nutrition reports that recommended creatine doses do not cause kidney damage or renal dysfunction in healthy individuals.
Creatine supplementation may increase serum creatinine concentration. This increase results from creatine’s conversion into creatinine and does not necessarily signal kidney dysfunction. Elevated creatinine readings should be interpreted within this context.
Creatine supplements should be avoided by those with chronic renal disease or those using potentially nephrotoxic medications.
Anyone with kidney issues should consult a physician before starting supplementation.
Creatine and Hair Loss
A 2009 study in college-aged males reported increased serum dihydrotestosterone concentrations after creatine supplementation. Levels increased by 56% after 7 days of loading and remained 40% higher after 14 days at maintenance. Dihydrotestosterone has been associated with male pattern baldness in genetically susceptible individuals, which led to concern about creatine’s impact on hair loss.
A 2025 randomized controlled trial enrolled 45 resistance-trained males (ages 18 to 40) and assigned them to receive either 5 grams of creatine monohydrate daily or a placebo for 12 weeks. The study measured total testosterone, free testosterone, dihydrotestosterone, and hair follicle health (hair density, follicular unit count, hair thickness).
Results showed no significant differences in dihydrotestosterone levels, hormone ratios, or hair growth parameters between the creatine and placebo groups. This study provides strong evidence against claims that creatine causes hair loss. Most available evidence does not support a link between creatine supplementation and hair loss.
Creatine and Steroids: Clearing Up Confusion
Creatine is not an anabolic steroid. The compounds have different chemical structures and mechanisms of action.
Creatine is an amino acid compound that supports adenosine triphosphate production. Steroids are synthetic compounds that impact hormonal pathways and stimulate muscle protein synthesis. Creatine is legal and permitted in major athletic organizations, while anabolic steroids are controlled substances.
Potential Side Effects
Most side effects from creatine are mild.
Gas, bloating, or stomach upset may occur, especially at higher doses during loading phases.
These effects generally diminish after loading or when using lower daily doses.
Water retention during loading is common, with an average gain of 2 to 4 pounds, primarily due to water weight.
Creatine increases total body water by drawing water into muscle cells.
Water retention from creatine occurs within muscle cells, not beneath the skin.
Increases in total body water are typically short-term and resolve within weeks after loading ends.
Creatine supplementation does not cause dehydration or muscle cramping.
No substantial scientific evidence links creatine to acne development.
What Creatine Does for Performance
The performance benefits of creatine center on high-intensity, short-duration efforts. Meta-analytic findings indicate that creatine supplementation has the most pronounced effect on short-duration activities of 30 seconds or less during high-intensity intermittent exercise. The specific aspects of anaerobic endurance performance improved by creatine were work and power output. Creatine supplementation supports:
Sprints and short bursts of speed
Heavy lifting and resistance training
Repeated high-intensity intervals
Power movements (jumping, throwing)
Recovery between sets during training
Creatine does not provide immediate energy like caffeine. It supports the phosphocreatine system, enabling greater work at high intensities and potentially improving training adaptations over time.
Body Composition Effects
Creatine supplementation does not increase fat mass. Increases in body mass are typically due to water retention and, over time, increased lean muscle tissue.
Creatine supports high-intensity exercise performance, enabling more repetitions, higher training volume, and intensity. This can accelerate muscle protein synthesis and promote lean muscle growth. Increased muscle mass may also support improvements in body composition when combined with appropriate training and nutrition.
Creatine for Female Athletes
Recent research has addressed the underrepresentation of women in creatine studies. Findings suggest that women may experience benefits similar to those in men, including increased strength, sports performance, and fatigue resistance.
Unique Physiological Considerations
Hormone-driven changes throughout the female reproductive system alter endogenous creatine synthesis, transport, and bioavailability.
Women tend to have lower baseline muscle creatine levels, potentially increasing responsiveness to supplementation.
Hormone-related changes are often overlooked in performance studies.
Creatine supplementation may be particularly beneficial during menstruation, pregnancy, the postpartum period, and the pre- and postmenopausal periods.
Creatine Across the Female Lifespan
Pre-menopausal women: Creatine supplementation appears to be effective for improving strength and exercise performance. Creatine may help buffer the impact of hormonal shifts during the menstrual cycle, especially in the luteal phase when energy levels often dip.
Perimenopausal and menopausal women: A 2025 randomized controlled trial specifically examining creatine in this population found that supplementation with medium-dose creatine hydrochloride was superior to placebo in enhancing reaction time, increasing frontal brain creatine levels, and favorably modulating serum lipid profiles.
Postmenopausal women: Research indicates benefits for skeletal muscle size and function with higher creatine doses of 0.3 g/kg/day. When combined with resistance training, creatine further supports body composition and bone mineral density.
Cognitive and Mood Benefits for Women
Women have lower brain creatine levels, especially in the frontal cortex (which is linked to mood, attention, and cognition).
Some studies suggest creatine supplementation may improve brain function, including memory and reasoning, in older women, particularly under stressful conditions such as sleep deprivation.
Creatine supplementation has been shown to support mood and cognition.
Higher dietary creatine intake is associated with lower depression rates.
Reproductive Health Associations
Dietary creatine intake of at least 13 milligrams per kilogram of body mass per day is associated with a reduced risk of irregular menstrual cycles, obstetric conditions, and pelvic pathology, based on U.S. data for women aged 12+.
Creatine Supplementation Summary Table
| Topic | Key Information |
|---|---|
| What is creatine? | Naturally occurring non-protein compound; 95% stored in skeletal muscle |
| Primary function | Regenerates adenosine triphosphate during high-intensity exercise |
| Daily endogenous production | 1-2 grams per day |
| Loading dose | 20-25g per day for 5-7 days (or 0.3g per kg body mass) |
| Maintenance dose | 3-5g per day (or 0.03-0.1g per kg body mass) |
| Time to saturation without loading | 2-4 weeks |
| Best form | Creatine monohydrate |
| Optimal timing | Post-workout or with meals; consistency matters most |
| Absorption enhancement | Take with 50g of protein and 50g of carbohydrates. |
| Weight gain during loading | 2-4 pounds (water retention in muscles) |
| Long-term safety data | Up to 30g per day for 5 years in healthy persons |
| Kidney safety | No harm to kidney function in healthy persons |
| Hair loss | No evidence of causal relationship (2025 study) |
| Legal status | Permitted by the International Olympic Committee and the National Collegiate Athletic Association |
| Best for | Short-duration, high-intensity exercise; power output; recovery between sets |
Beyond Athletic Performance
Research supports the benefits of creatine beyond performance, including:
Helping prevent or reduce injury severity
Enhancing rehabilitation
Supporting tolerance for heavy training loads
The International Society of Sports Nutrition recognizes several potentially beneficial clinical uses for creatine. The organization notes that restricting creatine use may increase risk for athletes in contact sports with head trauma or neurological injury risk.
A 2025 statement from the International Society of Sports Nutrition and leading researchers reported that there is no scientific basis for restricting the sale of creatine-containing products to children and adolescents, given evidence of dietary importance and safety.
Emerging research explores creatine’s potential for brain health, mood, and aging. Some studies suggest benefits for memory and concentration under stress or sleep deprivation. Early findings in women suggest potential benefits for muscle and bone health, particularly post-menopause.
Getting Started with Creatine
If you have read this far and decided to try creatine supplementation, here is a practical approach:
Step 1: Purchase creatine monohydrate from a reputable manufacturer with third-party testing certification, such as NSF Certified for Sport or Informed Choice.
Step 2: Decide on your approach. If you want rapid saturation and can tolerate potential bloating, use the loading protocol of 5 grams taken 4 times per day for 5-7 days. If you prefer a gentler start, begin with 3-5 grams per day and allow 2-4 weeks for full saturation.
Step 3: Take your creatine with food, ideally a meal containing protein and carbohydrates. Post-workout meals work well for this purpose.
Step 4: Maintain consistent daily intake. Missing days allows your creatine stores to begin depleting. The compound’s effects depend on maintaining elevated muscle concentrations over time.
Step 5: Give it time. Performance benefits typically become noticeable within 1-2 weeks after muscle saturation is reached.
Step 6: Stay hydrated. While creatine does not cause dehydration, adequate water intake supports optimal cellular function and increased water retention in muscle tissue.
Creatine FAQs
How much creatine should I take per day?
For most athletes, 3-5 grams of creatine monohydrate per day is sufficient. If using a loading protocol, take 20-25 grams per day, divided into 4-5 doses, for 5-7 days, then reduce to 3-5 grams per day for maintenance.
Does creatine cause weight gain?
Creatine causes an initial weight gain of approximately 2-4 pounds, primarily from water retention within muscle cells. This is not fat gain. Over time, creatine supports lean muscle growth when combined with resistance training.
Is creatine safe for my kidneys?
In healthy persons, creatine supplementation at recommended doses does not harm kidney function. Studies lasting up to 5 years have found no detrimental effects. Persons with existing kidney disease or those on nephrotoxic medications should consult a physician before supplementing.
Will creatine make me lose my hair?
The available scientific evidence does not support a link between creatine supplementation and hair loss. A 2025 randomized controlled trial assessing hair follicle health found no difference between creatine users and placebo recipients.
Can women take creatine?
Yes. Research shows women may benefit from creatine supplementation for strength, performance, and fatigue resistance. Women tend to have lower baseline muscle creatine levels, which may make them exceptionally responsive to supplementation.
Do I need to cycle creatine?
No. There is no evidence that cycling on and off creatine provides any advantage. Continuous daily supplementation maintains elevated muscle creatine stores and consistent performance benefits.
Should I take creatine on rest days?
Yes. Maintaining daily creatine intake, including on rest days, keeps your muscle stores saturated. Skipping days allows creatine levels to begin declining.
Is creatine banned in sports?
No. The International Olympic Committee and the National Collegiate Athletic Association permit the use of Creatine. It is legal and widely used across competitive athletics.
Does creatine give you energy like caffeine?
No. Creatine does not provide an immediate stimulant-like energy boost. It supports the phosphocreatine system that regenerates adenosine triphosphate during high-intensity efforts, allowing you to perform more work at high intensities.
What happens if I stop taking creatine?
Your muscle creatine stores will gradually return to baseline levels over several weeks. Any performance benefits dependent on elevated creatine stores will diminish. Lean muscle gained through enhanced training will remain if you continue training.
Can I mix creatine with protein shakes?
Yes. Creatine can be mixed into protein shakes, and the protein content may enhance absorption via insulin-mediated effects.
Does creatine cause bloating?
Some people experience temporary bloating during high-dose loading phases. Using the lower-dose approach of 3-5 grams can reduce bloating and gastrointestinal upset while still saturating muscles over 2-4 weeks.
The Bottom Line
Creatine monohydrate has established itself as the most extensively studied and effective supplement for athletes. The International Society of Sports Nutrition recognizes it as the most effective ergogenic nutritional supplement currently available for increasing high-intensity exercise capacity and lean body mass.
The research spans decades and thousands of participants across diverse populations. Safety data extend to long-term use at high doses in healthy persons. The concerns that persist in popular discourse, from kidney damage to hair loss, lack direct scientific evidence.
Increased phosphocreatine stores enable greater adenosine triphosphate regeneration during maximal efforts, translating to improved performance during training and greater adaptations over time. The compound is legal, affordable, and well-tolerated by most people.
The practical application is simple. Take 3-5 grams of creatine monohydrate daily with food, ideally near your workout. Be consistent. Give it time to work. That approach, maintained over months of training, is what produces results.
