A review of creatine supplementation in age-related diseases: more than a supplement for athletes

Abstract

Creatine is an endogenous compound synthesized from arginine, glycine and methionine. This dietary supplement can be acquired from food sources such as meat and fish, along with athlete supplement powders. Since the majority of creatine is stored in skeletal muscle, dietary creatine supplementation has traditionally been important for athletes and bodybuilders to increase the power, strength, and mass of the skeletal muscle. However, new uses for creatine have emerged suggesting that it may be important in preventing or delaying the onset of neurodegenerative diseases associated with aging. On average, 30% of muscle mass is lost by age 80, while muscular weakness remains a vital cause for loss of independence in the elderly population. In light of these new roles of creatine, the dietary supplement’s usage has been studied to determine its efficacy in treating congestive heart failure, gyrate atrophy, insulin insensitivity, cancer, and high cholesterol. In relation to the brain, creatine has been shown to have antioxidant properties, reduce mental fatigue, protect the brain from neurotoxicity, and improve facets/components of neurological disorders like depression and bipolar disorder. The combination of these benefits has made creatine a leading candidate in the fight against age-related diseases, such as Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, long-term memory impairments associated with the progression of Alzheimer’s disease, and stroke. In this review, we explore the normal mechanisms by which creatine is produced and its necessary physiology, while paying special attention to the importance of creatine supplementation in improving diseases and disorders associated with brain aging and outlining the clinical trials involving creatine to treat these diseases.

An Update on Effects of Creatine Supplementation on Performance: A Review

“…This reaction produces free-form CR and S-adenosyl-L-homocysteine [1,19,21]. Storage occurs predominantly in the skeletal muscle (approximately 95%) with the remaining 5% distributed between the heart, brain, liver, kidneys and testes [22]. The muscle fibres are unable to synthesize CR and it must be absorbed and transferred via the blood, through the use of a specific protein; CR transporter protein, which enables distribution of CR throughout cells.…”

“…The average CR pool (male: 70 kg) is approximately 120-140 g, although this varies depending on fat-free mass [23] and skeletal muscle fibre type [22]. In general, oral supplementation aims to enhance this CR pool, with research showing a maximum increase of approximately 20% following a high dosage loading programme [13].…”

“…While some claim this can lead to an increased load on both the liver and kidneys, empirical research is yet to find any such side effects in healthy individuals [26,27]. It is also worth noting that once supplementation has ceased, serum CR levels will return to their pre-supplementation level within a 30-day period [22]. Milk (1% Fat) 250 ml/8oz 0.05 Table 1: Creatine content as present in raw food products [28].…”

Creatine in Sport and Medicine

“…Akceptacja stosowania kreatyny budzi wiele kontrowersji i na przykład we Francji jest to zabronione [11]. W Stanach Zjednoczonych produkuje się rocznie ok. 4 mln kg tego związku o wartości 200 mln dolarów [12]. COMS (Centralny Ośrodek Medycyny Sportowej) i Komisja Medyczna PKOl (Polskiego Komitetu Olimpijskiego) [13], AIS (Australijski Instytut Sportu) [14], ISSN (Międzynarodo-we Towarzystwo Żywienia w Sporcie) [15], ADA (Amerykańskie Towarzystwo Dietetyczne), Towarzystwo Dietetyków Kanady oraz Amerykańska Szkoła Medycyny Sportowej [16] zakwalifikowały ten związek do grupy suplementów A. W grupie tej znajdują się środki o udowodnionej skuteczności rekomendowanej przez PKOl i COMS opierającej się na: "rzetelnych badaniach naukowych opublikowanych w recenzowanych czasopismach, potwierdzających korzystny wpływ na zdolność do wysiłku fizycznego" [13].…”

“…Syntezowana jest z 3 aminokwasów: metioniny, argininy i glicyny [9,12,17] w trzustce, nerkach, wątrobie [9] i w niewielkich ilościach w mózgu oraz jądrach [17]. Jej zawartość w organizmie wynosi około 120-140 gramów [18].…”