Creatine

With comparable resistance training, chest press gains averaged 2.16 kg more (95% CI 1.13–3.18, 52 comparisons).

Study findings. With comparable resistance training, chest press gains averaged 2.16 kg more (95% CI 1.13–3.18, 52 comparisons).

Comparator — Control groups from the included trials

Across 23 comparisons with comparable resistance training, leg press gains averaged 7.56 kg more. In the overall analysis of 31 comparisons, the estimated difference in gains between groups was 3.13 kg (95% CI −0.74 to 7.00).

Study findings. Across 23 comparisons with comparable resistance training, leg press gains averaged 7.56 kg more. In the overall analysis of 31 comparisons, the estimated difference in gains between groups was 3.13 kg (95% CI −0.74 to 7.00).

Comparator — Control groups from the included trials

The pooled estimate for the squat was +5.64 kg (95% CI 3.87–7.40), an average across different studies.

Study findings. The pooled estimate for the squat was +5.64 kg (95% CI 3.87–7.40), an average across different studies.

Comparator — Control groups from the included trials

For average power across a series of short sprints, the pooled estimate was an SMD of 0.61 (p = 0.002). This value does not express a percentage gain.

Study findings. For average power across a series of short sprints, the pooled estimate was an SMD of 0.61 (p=0.002). This value does not express a percentage gain.

Comparator — Placebo

There was no statistically convincing overall advantage in peak power across the sprint series.

Study findings. There was no statistically convincing overall advantage in peak power across the sprint series.

Comparator — Placebo

There was no statistically convincing overall advantage in how much performance declined across the sprint series.

Study findings. There was no statistically convincing overall advantage in how much performance declined across the sprint series.

Comparator — Placebo

For direct measurements of muscle size, the mean standardized estimate was 0.11, with a 95% Bayesian credible interval of −0.02 to 0.25. The estimated effect is small and imprecise, and an individual gain is not guaranteed.

Study findings. The Bayesian standardized estimate of the increase in muscle size was 0.11, with a 95% credible interval of −0.02 to 0.25. An individual gain is not guaranteed.

Comparator — Placebo

No significant improvement between groups was found in continuous cycling tests lasting 3, 6, and 12 minutes.

Study findings. No significant improvement between groups was found in continuous cycling tests lasting 3, 6, and 12 minutes.

Comparator — Placebo

No significant advantage was found in a standalone 10-second sprint test. The continuous 3-, 6-, and 12-minute rides were conducted separately.

Study findings. No significant advantage was found in a standalone 10-second sprint test. The continuous 3-, 6-, and 12-minute rides were conducted separately.

Comparator — Placebo

With identical training, the pooled strength estimate was g=0.31 (95% CI 0.18–0.45).

Study findings. With identical training, the pooled strength estimate was g=0.31 (95% CI 0.18–0.45).

Comparator — The same resistance training in the control groups, usually with placebo

For physical function tests, the mean standardized difference was 0.47 (95% CI −0.08 to 1.03). The interval includes zero, the value for no difference.

Study findings. For physical function tests, the mean standardized difference was 0.47 (95% CI −0.08 to 1.03). The interval includes zero, the value for no difference.

Comparator — Resistance training in the control group

The time to walk 80 m at a usual pace changed from 48.6 to 47.1 s with creatine and from 48.3 to 48.2 s with placebo (p = 0.0008). The study did not assess walking with a load.

Study findings. The time to walk 80 m at a usual pace changed from 48.6 to 47.1 s with creatine and from 48.3 to 48.2 s with placebo (p=0.0008). The study did not assess walking with a load.

Comparator — Placebo

The group-by-time interaction test did not detect a difference between groups in how femoral neck bone mineral density changed over time (p = 0.84).

Study findings. The group-by-time interaction test did not detect a difference between groups in how femoral neck bone mineral density changed over time (p=0.84).

Comparator — Placebo

The group-by-time interaction test did not detect a difference between groups in how total hip bone mineral density changed over time (p = 0.69).

Study findings. The group-by-time interaction test did not detect a difference between groups in how total hip bone mineral density changed over time (p=0.69).

Comparator — Placebo

No convincing overall advantage was found for lumbar spine bone mineral density.

Study findings. No convincing overall advantage was found for lumbar spine bone mineral density.

Comparator — Placebo

Two calculated measures of structure at the narrow part of the femoral neck changed less. The measure of bending resistance went from 1.35 to 1.34 cm³ versus 1.34 to 1.28 cm³, and the measure of cortical stability went from 10.8 to 11.1 versus 11.0 to 11.6. Fracture risk cannot be assessed from these measurements.

Study findings. Two calculated measures of structure at the narrow part of the femoral neck changed less. The measure of bending resistance went from 1.35 to 1.34 cm³ versus 1.34 to 1.28 cm³, and the measure of cortical stability went from 10.8 to 11.1 versus 11.0 to 11.6. Fracture risk cannot be assessed from these measurements.

Comparator — Placebo

In the pooled analysis of different tests, including sprint and agility tests, performance was higher on average (g=0.30). The gain may differ for any given exercise.

Study findings. In the pooled analysis of different tests, including sprint and agility tests, performance was higher on average (g=0.30). The gain may differ for any given exercise.

Comparator — placebo or control with the same background regimen

The studies found no convincing overall improvement on the specific memory tests.

Study findings. The studies found no convincing overall improvement on the specific memory tests.

Comparator — Placebo

The studies found no convincing overall improvement in attention on the tests reviewed.

Study findings. The studies found no convincing overall improvement in attention on the tests reviewed.

Comparator — Placebo

In a review of 11 trials with 1,093 participants, the pooled estimate converts to about 2.2 points in favor of creatine on the 17-item Hamilton scale. The threshold for a noticeable change is 3 points. Confidence in the result is very low.

Study findings. In a review of 11 trials with 1,093 participants, the pooled estimate converts to about 2.2 points in favor of creatine on the 17-item Hamilton scale. The threshold for a noticeable change is 3 points. Confidence in the result is very low.

Comparator: Placebo, with any existing background care continued in both groups

The total rise in glucose during the glucose challenge test decreased more than with placebo (p=0.034).

Study findings. The total rise in glucose during the glucose challenge test decreased more than with placebo (p=0.034).

Comparator: Dextrose, with moderate aerobic training in both groups

Fasting insulin levels did not differ between groups and did not change significantly over follow-up.

Study findings. Fasting insulin levels did not differ between groups and did not change significantly over follow-up.

Comparator: Dextrose, with moderate aerobic training in both groups

The calculated HOMA index of insulin resistance did not differ between groups and did not change significantly over follow-up.

Study findings. The calculated HOMA index of insulin resistance did not differ between groups and did not change significantly over follow-up.

Comparator: Dextrose, with moderate aerobic training in both groups

Maximal elbow flexor strength was higher immediately after exercise and at 48, 96, and 168 hours. The study examined a single bout of unfamiliar exercise.

Study findings. Maximal elbow flexor strength was higher immediately after exercise and at 48, 96, and 168 hours. The study examined a single bout of unfamiliar exercise.

Comparator: Microcrystalline cellulose

Soreness did not differ in the 2024 trial. In the 2025 trial, soreness was lower immediately after exercise and at 48 and 96 hours. Both trials exercised the elbow flexors.

Study findings. Soreness did not differ in the 2024 trial. In the 2025 trial, soreness was lower immediately after exercise and at 48 and 96 hours. Both trials exercised the elbow flexors.

Comparator: Microcrystalline cellulose

There was no clear change in mean time for single 50 m and 100 m sprints (SMD −0.05, 95% CI −0.26 to 0.15).

Study findings. There was no clear change in mean time for single 50 m and 100 m sprints (SMD −0.05, 95% CI −0.26 to 0.15).

Comparator — Placebo

During a night without sleep, performance on some tests declined less than with placebo. This applied to specific tasks assessing logical reasoning, arithmetic, speech processing speed, and sustained attention.

Study findings. During a night without sleep, performance on some tests declined less than with placebo. This applied to specific tasks assessing logical reasoning, arithmetic, speech processing speed, and sustained attention.

Comparator: Resistant dextrin

No clear advantage was found on any test. The difference fell within the specified limits only for two measures of reaction speed and for the number of correct responses per minute on one memory task.

Study findings. No clear advantage was found on any test. The difference fell within the specified limits only for two measures of reaction speed and for the number of correct responses per minute on one memory task.

Comparator: Tapioca

Over 12 weeks, no differences were found in the measured hair characteristics, including hair density and thickness.

Study findings. Over 12 weeks, no differences were found in the measured hair characteristics, including hair density and thickness.

Comparator: Maltodextrin, 5 g/day

The overall lipid analysis found no clear difference between groups over 12 weeks. The study found no clear effect on total cholesterol specifically.

Study findings. The overall lipid analysis found no clear difference between groups over 12 weeks. The study found no clear effect on total cholesterol specifically.

Comparator — Placebo

The overall lipid analysis found no clear difference between groups over 12 weeks. The study found no clear effect on LDL cholesterol specifically.

Study findings. The overall lipid analysis found no clear difference between groups over 12 weeks. The study found no clear effect on LDL cholesterol specifically.

Comparator — Placebo

The overall lipid analysis found no clear difference between groups. In an additional comparison of participants without an exercise and nutrition program, HDL cholesterol changed more favorably with creatine than with placebo.

Study findings. The overall lipid analysis found no clear difference between groups. In an additional comparison of participants without an exercise and nutrition program, HDL cholesterol changed more favorably with creatine than with placebo.

Comparator — Placebo

The overall lipid analysis found no clear difference between groups. In an additional comparison of participants without an exercise and nutrition program, triglycerides changed more favorably with creatine than with placebo.

Study findings. The overall lipid analysis found no clear difference between groups. In an additional comparison of participants without an exercise and nutrition program, triglycerides changed more favorably with creatine than with placebo.

Comparator — Placebo

After rehabilitation, distance increased by 84 m in the creatine group and 83.8 m in the placebo group (p=1.0).

Study findings. After rehabilitation, distance increased by 84 m in the creatine group and 83.8 m in the placebo group (p=1.0).

Comparator: Lactose alongside the same pulmonary rehabilitation program

Over one week, 14 men rated their sleep better with creatine than with placebo (d=0.81, p=0.009). Most objective sleep measures did not differ significantly.

Study findings. Over one week, 14 men rated their sleep better with creatine than with placebo (d=0.81, p=0.009). Most objective sleep measures did not differ significantly.

Comparator — Placebo

By week six, the sleep regularity measure was 7.4 percentage points higher than with placebo (p=0.015 after adjustment for baseline values). This finding came from an exploratory analysis.

Study findings. By week six, the sleep regularity measure was 7.4 percentage points higher than with placebo (p=0.015 after adjustment for baseline values). This finding came from an exploratory analysis.

Comparator — Placebo

Total sleep duration in the study of men did not differ significantly (p = 0.81).

Study findings. Total sleep duration in the study of men did not differ significantly (p=0.81).

Comparator — Placebo

In an exploratory analysis, women taking creatine reported fewer days with increased temperature sensitivity. This measure did not assess hot flash frequency.

Study findings. In an exploratory analysis, women taking creatine reported fewer days with increased temperature sensitivity. This measure did not assess hot flash frequency.

Comparator — Placebo