Creatinine is a waste product produced by our muscles as part of daily activity, exertion etc. Kidneys filter out creatinine from our blood and pass it out through urine. Creatinine is usually measured in milligrams per deciliter (mg/dL) or nanograms per millilitre (ng/mL). Doctors use creatinine levels to diagnose kidney disease and other conditions that affect kidney function, such as diabetes or high blood pressure.

A normal creatinine level in blood ranges from 0.7 mg/dL to 1.3 mg/dL. This range however is subjective to many other conditions such as age, gender, muscle mass, recent exercise activity etc.

What does a creatinine test show about your health?

Creatinine is a waste product that’s produced when your body breaks down protein. The kidneys filter creatinine out of the blood and into the urine, where it can be measured to see how well they’re working. High levels of creatinine may indicate that there is a problem with your kidneys, but this isn’t always the case—it can also mean you’re eating too much meat or drinking too much alcohol. Creatinine levels may be higher after even a heavy exercise or strenuous physical exertion, which in most cases is not a reason to be concerned about.

The creatinine test is useful in monitoring kidney health. However, serum creatinine level alone is not sufficient to make conclusions about kidney health. Your doctor might also prescribe other tests including urine analysis. The presence of protein (albumin) in the urine may be yet another indication of impaired kidneys. Parameters such as GFR (Glomerular Filtration Rate), blood urea & uric acid levels, ACR (albumin to creatinine ratio) etc are often read in conjunction by your doctor to assess any sort of kidney damage.

How do doctors test for creatinine?

Creatinine can be measured in the blood (serum creatinine), in urine (creatinine clearance) and even in saliva. Creatinine clearance is a timed test where entire urine is collected for a longer duration (usually 24 hours) and the amount of creatinine is checked. This is hence slightly inconvenient a test but gives a better measure of how effectively the creatinine from blood is flushed out into the urine.

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What leads to a high creatinine level?

The most common cause of kidney damage and elevated creatinine levels is uncontrolled diabetes. Elevated blood glucose levels over a longer duration can damage many organs such as kidneys, eyes, nerves etc. Creatinine levels can be high in other conditions also such as –

• Autoimmune Kidney diseases, chronic kidney failure.
• Lack of water intake/dehydration
• Muscle breakdown
• Highly strenuous exercise
• Consuming large amounts of red meat also can cause a temporary increase in creatinine levels
• Certain medications also can cause a temporary rise in serum creatinine levels. In such cases, please consult your physician

What are the symptoms of high creatinine levels or kidney damage?

If you have creatinine levels, the symptoms you may experience may include:

• Muscle weakness. This can occur as a result of kidney failure and lead to muscle cramps, lack of energy and fatigue.
• High blood pressure due to the kidney’s inability to manage the blood pressure
• Nausea and vomiting. This is caused by an increase in acidity in your body due to changes in your kidneys’ ability to filter out waste products from the blood
• Puffiness around eyes
• Pedal Edema (swelling of the feet and ankles – pitting edema)
• Those with kidney damage are also prone to anaemia and low vitamin d levels.

At extremely high creatinine levels, your doctor may suggest dialysis or a kidney transplant depending on the severity and nature of the disease.

Diet for High Creatinine / Diet for Kidney Damage

Kidney damage is a serious health condition and requires help from a nutrition expert who understands clinical conditions and their complications. Here are some of the points to consider while preparing for a diet suitable for CKD (Chronic Kidney Disease)

• Do not consume too much protein in the diet. Excessive intake of protein can create a higher load on the kidney and exacerbate the kidney damage
• Do not consume too much salt
• Reduce food rich in sodium. Avoid preserved and packaged food – they are high in sodium content. Eat fresh food as much as possible
• Reduce the consumption of raw food. Peel off the skin from vegetables and fruits such as apples that is more prone to be exposed to pesticides
• In case of chronic kidney damage, leaching the vegetables (soak the cut vegetables in water for a couple of hours and drain the water out) may be required. This is done in order to drain out potassium and phosphorus from the food
• Water intake may need to be regulated depending on the severity of the kidney condition. Always ask your doctor about the right amount of water for consumption and stick to the same
• The DASH diet (Dietary Approach to Stop Hypertension) is a dietary habit to control high blood pressure and is recommended for people with heart conditions or kidney damage. However, in case of chronic kidney damage, a DASH diet with certain modifications to reduce potassium, phosphorus etc may be required.

The amount of protein, potassium, phosphorus and water intake can vary from person to person based on the extent of kidney damage. Always consult your doctor before making any sort of drastic dietary changes.

Also READ: Kidney Stones

How is Creatinine different from Creatine?

People often get confused between creatinine and creatine. Creatinine is a metabolic waste (or byproduct) when muscles use creatine to produce energy and aid muscle contraction. In other words – creatine is a molecule that supplies energy to muscles, while creatinine is a waste product of creatine. Athletes commonly use creatine supplementation to improve their exercise and athletic performances, in the form of creatine monohydrate.

Creatine can be synthesized in the liver and kidneys, but it also comes from foods such as meat, fish and beans. It is stored in our muscles and is also present in the brain. Creatine supplementation is widely used and is one of the most researched and safest supplements, especially for strength training and high endurance athletes. It also has the purported benefits of improving (brain) cognitive function and protecting against diseases like Alzheimer’s disease or Parkinson’s disease. The scientific evidence backing up these claims is, however, not conclusive yet and still requires a lot of research.

Creatine supplementation is safe and effective for high endurance and weight training, as long as the kidney function is healthy. Up to 5 grams per day is safe and recommended as a pre-workout. Creatine loading is a practice among some athletes where 20 gms or more is consumed for a period of 7 – 10 days. This is not recommended and does not provide any added benefits over  5 gms daily, especially when compared after 3 weeks.

Also READ: NuvoVivo & World Kidney Day Foundation

Conclusion

The bottom line is that creatinine tests can help doctors understand how well your kidneys are working. If you have kidney disease, then a high level of creatinine in your blood could be an indication that you have damage to these organs or that you have other issues affecting your body’s ability to filter out waste products from the blood. However, if you’re healthy and don’t have any kidney problems, then testing for this substance may not really be necessary at all! Serum Creatinine level has to be analysed with other parameters such as GFR, Urine Albumin etc by your doctor to conclusively diagnose the underlying cause and the course of treatment.