Establishing Dietary Reference Intakes for Creatine in Adults

Area of Science:

• Nutritional Science
• Human Physiology
• Dietary Reference Intakes

Background:

• Creatine is crucial for energy metabolism, stored in muscles and brain.
• Dietary intake is vital for maintaining creatine status, especially for those avoiding animal products.
• No established dietary reference intakes (DRIs) for creatine currently exist for adults.

Purpose of the Study:

• To estimate daily creatine needs in adults aged 19-65 years.
• To propose adequate intake (AI) values for creatine based on physiological data.
• To identify populations at risk of creatine insufficiency.

Main Methods:

• Integrated physiological data on creatine turnover and endogenous synthesis.
• Assessed population-level dietary exposure to creatine.
• Calculated creatine losses via conversion to creatinine and estimated dietary requirements.

Main Results:

• Estimated daily creatine losses: 20 mg/kg/day (men) and 15 mg/kg/day (women).
• Endogenous synthesis covers 73% of losses; diet supplies the remaining 27%.
• Proposed AI: 5.4 mg/kg/day (men) and 4.1 mg/kg/day (women).

Conclusions:

• Established the first evidence-based creatine AI values for adults.
• Creatine is a conditionally essential nutrient, requiring dietary planning for at-risk groups.
• Identified vegetarians, vegans, and older adults as potentially susceptible to creatine insufficiency.