The best creatine supplement for longevity in 2026 is a pure micronized creatine monohydrate — ideally Creapure® branded — taken at 5 g/day. Creatine monohydrate is the most studied form (over 1,000 published trials) and the only form repeatedly shown to preserve muscle, support brain function, and improve recovery in adults over 40. There is no evidence that the more expensive forms (HCL, ethyl ester, nitrate) outperform plain monohydrate.

Creatine is no longer just a "lifter's supplement". Modern aging research positions it as a top-3 highest-evidence longevity intervention you can buy at the supermarket. Three reasons:

1. Sarcopenia prevention. Adults lose 3–8% of muscle mass per decade after age 40. A 2014 meta-analysis (Chilibeck et al.) showed creatine + resistance training increased lean mass gains by ~1.4 kg over training alone in older adults.

2. Brain energy and cognition. A 2018 meta-analysis (Avgerinos et al., Experimental Gerontology) found creatine improved short-term memory and reasoning in healthy adults — with the largest effects in older subjects and vegetarians.

3. Bone and recovery support. RCTs show creatine + resistance training slows bone mineral density loss in postmenopausal women better than training alone.