Postprandial serum creatinine increase in normal subjects after eating cooked meat

Area of Science:

• Biochemistry
• Human Nutrition
• Clinical Chemistry

Background:

• Serum creatinine is a common biomarker for kidney function.
• Dietary factors, particularly meat intake, can influence serum creatinine levels.
• The effect of cooked versus raw meat on serum creatinine requires clarification.

Purpose of the Study:

• To investigate the impact of cooked meat ingestion on postprandial serum creatinine concentrations.
• To compare the effects of cooked versus raw meat on serum creatinine.
• To determine the source of elevated serum creatinine after meat consumption.

Main Methods:

• Participants consumed meals containing either cooked or raw meat.
• Serum creatinine levels were measured at regular intervals postprandially.
• Creatinine clearance was assessed.
• Serum samples were analyzed using conventional and ion exchange methods to rule out interfering substances.

Main Results:

• Ingestion of cooked meat led to a significant postprandial increase in serum creatinine.
• Raw meat consumption did not affect serum creatinine levels.
• A peak in serum creatinine was observed approximately 3 hours after meals.
• No changes in creatinine clearance were detected.
• Analysis confirmed that the increase was due to creatinine, not other chromogens.
• Boiling meat was identified as the process that converts creatine to creatinine.

Conclusions:

• The postprandial rise in serum creatinine after consuming cooked meat is a dietary effect, not indicative of kidney dysfunction.
• Cooking meat, specifically boiling, generates creatinine from creatine.
• Clinicians should consider dietary intake of cooked meat when interpreting serum creatinine levels.