What are the potential harms of taking 20g of creatine?

Creatine 20g Daily: Safety Profile

Taking 20g of creatine daily as a loading dose for 5-7 days is safe and well-established in healthy individuals, with no negative health effects when following appropriate protocols, though this dose should be divided into four equal 5g doses throughout the day rather than taken as a single bolus. 1

Established Safety at 20g Loading Dose

The 20g daily dose is specifically recommended as a standard loading protocol by the British Journal of Sports Medicine guidelines for elite athletes 1:

• Loading phase protocol: ~20g/day divided into four equal daily doses (5g each), for 5-7 days 1
• This is followed by a maintenance phase of 3-5g/day 1
• No negative health effects have been documented following appropriate protocols 1

Expected Effects (Not Harms)

The primary physiological change at this dose is:

• Potential 1-2 kg body mass increase after creatine loading 1
• This weight gain is primarily water retention due to the osmotic effect of increased intramuscular creatine stores 2
• This is a predictable effect, not an adverse event 1

Documented Safety Evidence

Short-term Safety

• Creatine supplementation up to 8 weeks with high doses (20g) has not been associated with major health risks 2
• The most common "adverse effect" is transient water retention in early supplementation stages 3
• Gastrointestinal disturbances and muscle cramps are occasionally reported but remain anecdotal and not necessarily linked to creatine itself 4, 5

Organ Function

Liver and kidney function remain normal in healthy subjects:

• No changes in liver enzymes or urea production during medium-term (4 weeks) supplementation 5
• No adverse effects on renal function during short-term (5 days), medium-term (9 weeks), or long-term (up to 5 years) supplementation when monitored by clearance methods and urine protein excretion 4, 5
• Despite unproven allegations, kidneys show no change in glomerular filtration, urea, or albumin excretion rates in healthy subjects 4

Important Contraindications

Avoid high-dose creatine (>3-5g/day) in specific populations:

• Individuals with pre-existing renal disease 4
• Those with potential risk for renal dysfunction: diabetes, hypertension, reduced glomerular filtration rate 4
• When combined with other supplements or taken at higher than recommended doses for several months, isolated cases of liver and renal complications have occurred 3

Practical Implementation

To minimize any potential issues:

• Divide the 20g into four 5g doses throughout the day 1
• Take with meals to improve gastrointestinal tolerability 3
• Concurrent consumption with mixed protein/carbohydrate (~50g each) may enhance muscle creatine uptake via insulin stimulation 1
• Ensure adequate hydration given the osmotic water retention effect 2
• Limit loading phase to 5-7 days maximum, then reduce to 3-5g/day maintenance 1

Alternative Lower-Dose Approach

If the 1-2 kg body mass increase is undesirable:

• Lower dose approaches of 2-5g/day for 28 days can avoid the associated increase in body mass while still being effective 1
• This bypasses the loading phase entirely but takes longer to saturate muscle creatine stores 1

Monitoring Considerations

While not required for healthy individuals, consider baseline kidney function assessment in those with risk factors for renal dysfunction before initiating supplementation 4. Regular monitoring during supplementation is compulsory only when idiosyncratic reactions are suspected, as large amounts of exogenous amino-containing substances increase hepatic and renal load 5.