Creatine Powder Storage, Clumping, Taste and Expiry

Dry powder

• A 2022 review states monohydrate is very stable in powder form, showing no signs of degradation to creatinine over years, even at elevated temperatures. [1]
• It cites a report that powder showed no sign of degrading to creatinine at up to 40 degrees C (104 degrees F) for more than three years, and only trace creatinine after 44 months at 60 degrees C (140 degrees F). [1]
• Some creatine salts are less stable. The review reports that storing one salt, tri-creatine citrate, at 40 degrees C for 28 days produced 770 ppm creatinine, compared with no measurable amount for monohydrate powder. [1]
• A 2002 lab study found commercial monohydrate loses its water at about 97-125 degrees C, and forms creatinine at higher temperatures still. [3] That is dry heat in a laboratory, not cooking in food.

These are laboratory results on pure ingredient, not on a retail tub that has been opened many times. Proper evidence not found for effects of humidity or repeated opening on retail creatine tubs (we searched PubMed for creatine powder storage and stability).

Clumping

Proper evidence not found for why powders clump or whether clumped powder is still fine to use; the sources we searched did not address it. Ask the maker or a pharmacist if a product looks, smells or tastes unusual, and do not use a product if you suspect contamination. Related: Product quality and contamination.

Mixing, hot drinks and solubility

• Monohydrate dissolves slowly: about 6 g per liter of water at 4 degrees C, 14 g/L at 20 degrees C, 34 g/L at 50 degrees C and 45 g/L at 60 degrees C. [1]
• Early studies gave creatine in warm to hot water or hot tea, and the review says residue left in the glass has no effect on bioavailability. [1] A 2021 paper says solubility has no influence on tissue uptake. [2]
• In solution, creatine degrades to creatinine faster as pH decreases and temperature rises. [1] In a study the review cites, at 25 degrees C degradation rose from 4% at pH 5.5 to 12% at pH 4.5 and 21% at pH 3.5. [1] The review suggests consuming it right after mixing in an acidic drink, or refrigerating and consuming within a couple of days. [1]
• Proper evidence not found for how much creatine is lost in hot coffee or hot tea specifically (we searched PubMed for creatine in hot beverages). Whether creatine in a hot drink works as well as in a cool one is not described in the sources we read.

Ready-made drinks and liquids

A 2003 lab study of effervescent powders containing di-creatine citrate dissolved in water found 90% creatine degradation within 45 days at room temperature, and 80% in the fridge. [4] A 2021 paper says efforts to make stable beverages with studied amounts have been unsuccessful. [2] See how formats differ.

Taste

Proper evidence not found. The sources we read did not describe taste. Added flavors and sweeteners appear in the ingredient list; see Reading a creatine label.

Expiry

FDA guidance says expiration dating is not required on dietary supplement labels, though a firm may include it if supported by valid data. [5] (That page is dated 2005; check current rules.) Proper evidence not found for how long an opened retail tub of creatine stays good. If a date is printed, it is the maker's date. For general supplement shelf-life questions see Comparing supplement labels.

Creatinine is a different substance from creatine

Creatinine is the breakdown product that kidneys filter and that blood tests measure. A 2021 paper says short-term rises in blood or urine creatinine from creatine supplements are unlikely to reflect lower kidney function. [2] The same paper cautions about using blood creatinine to estimate kidney function in people who take creatine. [2] If you have kidney disease, take medicines that affect the kidneys, or are pregnant or breastfeeding, ask a clinician first; see Creatine and kidney disease and Medication interactions.