What is Creatinine?
Creatinine is a chemical waste product produced by the normal metabolism of muscles in the body. It is derived from creatine, an amino acid the liver makes and stored in the muscles. The process of creatinine production involves the breakdown of creatine, which enters your bloodstream. Your kidneys play a crucial role in removing creatinine from your blood, after which it exits your body through urination [1].
Creatinine is an endogenous compound, meaning the body naturally produces it. It is an essential renal (kidney) function indicator routinely monitored in clinical labs. The serum creatinine level assesses how well your kidneys work [2].
The usual range of creatinine levels varies according to body size and muscle mass. For men, the normal range is between 0.6 and 1.2 mg/dl, while for women, it is between 0.5 and 1.1 mg/dl [1]. However, these levels can be affected by factors such as nutritional status, muscle mass, age, and sex [3].
Uses
Creatinine has several uses in medical and health contexts.
As discussed, one of the primary uses of creatinine is in assessing kidney function. The creatinine level in the blood can indicate how well your kidneys are working. High creatinine levels may suggest that your kidneys are damaged and not functioning properly [4].
Creatinine blood tests are often performed alongside other laboratory tests, such as a blood urea nitrogen (BUN) test and a basic metabolic panel (BMP) or comprehensive metabolic panel (CMP). These tests are done during routine physical exams to help diagnose certain diseases and check for kidney function problems [4].
In addition to assessing kidney function, creatinine has been studied for its anti-inflammatory activity. It effectively suppresses various substances' inflammatory responses [5].
Dietary supplements, such as creatine, can also influence creatinine levels. Some athletes use creatine supplements to enhance performance, but these can lead to elevated plasma creatinine levels. However, these elevated levels do not necessarily indicate kidney dysfunction [6, 7].
Furthermore, creatinine levels can be affected by diet. Eating large amounts of protein, particularly red meat, can temporarily increase creatinine levels [8].
Is creatinine in energy drinks safe?
Creatinine, often confused with creatine, is not typically an ingredient in energy drinks. However, creatine, a popular supplement among athletes for enhancing performance, is sometimes found in these beverages.
The safety of creatine in energy drinks has been discussed in several studies. Creatine is usually considered safe for healthy adults when used at recommended doses. Short and long-term creatine supplementation, ranging from 5 days to 5 years, with doses from 5 g/day to 30 g/day, showed no significant effects on kidney function in healthy athletes and bodybuilders without underlying kidney diseases [9].
However, caution is advised for individuals with pre-existing kidney disease or those taking potentially nephrotoxic medications. There have been a few case reports of renal dysfunction associated with creatine use in these populations.
Regardless of creatine content, energy drinks have been related to potential health risks. These beverages can increase blood pressure, leading to conditions such as hypertension, tachycardia, and nervousness, which can result in cardiovascular disorders.
In conclusion, while creatine in energy drinks is generally safe for healthy individuals, it may pose risks for those with kidney issues. Furthermore, the consumption of energy drinks, in general, should be done with caution due to potential hazards.