This paper delineates the challenges linked to estimating creatine intake from a typical diet, and explores opportunities to improve the assessment of population-wide creatine intake.
This special article explores creatine requirements for infants aged 0 to 12 months, presents a summary of creatine content in human milk, and proposes reference intakes for creatine in this population.
The mean creatine intake of 0.83 g per day for pregnant women is ∼11% above the estimated dietary creatine requirements. However, approximately 6 out of 10 pregnant women (57.2%) consumed creatine below the recommended amounts for an adult female, suggesting a possible risk of creatine malnutrition in this population.
The average daily intake of creatine across the entire sample was 0.70 ± 0.78 g (95% confidence interval [CI], from 0.69 to 0.71) and 13.1 ± 16.5 mg/kg body weight (95% CI, from 13.0 to 13.2). A significant negative trend for dietary creatine intake was found in infants (r = − 0.019; P = 0.042), and children and adolescents (r = − 0.024; P < 0.001).
Nonhuman milk, infant formulas, and other milk products were a source of creatine in 438 out of 597 children (73.4%), and creatine-containing meat-based foods were consumed by 205 children (34.3%). A total of 149 children (24.9%) were exclusively fed with breast milk (number of breastfeeding sessions 1–31 per day). The mean dietary intake of creatine across the sample was 0.28 ± 0.24 g/day (95% confidence interval, from 0.25 to 0.30).
The average intake of creatine in the U.S. population is 1.38 g/d. Of the studied population, 42.8% have an average intake below the recommended levels of 1 g/d of dietary creatine, indicating widespread creatine malnutrition in the U.S. population.
After salmon intake, serum concentrations of 1-MeHis and creatine, and urine concentrations (relative to creatinine) of 1-MeHis and creatine were increased when compared to control group.
The branched-chain amino acids, creatine, lysine, 2-aminobutyrate, glutamine, glycine, trimethylamine, and 1 unidentified metabolite were among the most important metabolites in the discriminating patterns in relation to intake of both meat and other animal products.
Previous risk assessments (AESAN, 2012; EFSA, 2004; SCF, 2000; VKM, 2010) all concluded
that creatine supplementation with 3.0 g/day is unlikely to cause adverse health effects in
adults. This is supported by human and animal data obtained in a literature search and
assessed in the present report.
Metabolite super-pathways affected by meat consumption were primarily amino acids, in particular creatine, trans-4-hydroxyproline and pyroglutamine. We report a novel association between reported red meat intake and trans-4-hydroxyproline, an amino acid that forms part of the collagen structure with elevated levels observed following gelatin consumption. We also identified a unique association between reported intakes of red meat and poultry and circulating creatine levels, of which red meat is the major source and vegetarians have lower blood levels.