Also known as: Estimated glomerular filtration rate
Estimated glomerular filtration rate (eGFR) is a measure of how well your kidneys function.
GFR is the amount of blood that is filtered every minute by tiny filters in the kidneys called glomeruli [R].
When kidney function declines due to damage or disease, GFR decreases and waste products that are normally released in the urine start to appear in the blood.
Your eGFR is calculated based on your blood creatinine levels, sex, age, and race. Creatinine is a waste product that is normally filtered by the kidneys and released into the urine at a relatively steady rate. When kidney function decreases, less creatinine is removed and levels in the blood increase.
Early detection of kidney dysfunction is important to prevent further kidney damage. Conditions such as wasting disease and obesity require alternative ways to obtain eGFR. For body builders, high muscle mass may lead to underestimation of eGFR when using creatinine [R].
Range
mL/min/1.73 m2
Critical < 29.99
Low 30 - 59.99
Sub-Optimal 60 -
89.99 Optimal 90 - 120
Supra-optimal > 120.01
Optimal
Your eGFR is within the normal range! Your kidneys are likely functioning optimally, and are able to efficiently filter toxins out of your body.
Low
Your eGFR is below the normal range! Levels in this range mean you have moderately decreased kidney function. The lower your value, the less efficiently your kidneys are working. It is important to monitor your values. Levels that stay below 60 mL/min/1.73 m2 for 3 or more months are a sign of chronic kidney disease. Alternatively, low GFR may be caused by: Eating cooked meat before the test [R]. This increases creatinine levels in the blood. Starvation and long fasting periods [R] Bodybuilding and creatine supplementation [R] Other factors that can increase creatinine in the blood, such as dehydration [R] Drugs such as NSAIDs and ACE inhibitors (or angiotensin receptor blockers) [R] These increase your risk of chronic kidney disease: High blood pressure [R, R] Diabetes [R, R] Heart disease [R] Obesity [R] Smoking [R, R] A family history of kidney disease [R] Age (being 60 years old and above) [R] Previous kidney injury [R] Low birth weight [R, R]
Aim for a healthy weight [R, R]. Lose weight if overweight. Consume a diet rich in fruits and vegetables [R]. Quit or reduce smoking [R, R, R]. Exercise for at least 30 minutes several times per week [R, R, R, R]. Make sure your blood pressure is in the healthy range (around 120/80) [R, R]. Control your blood sugar levels if you have diabetes [R, R]. Avoid lemongrass tea as it can decrease eGFR [R]. Check your creatinine marker for more lifestyle and supplement suggestions.
High
A high eGFR is usually not of concern, at least when it comes to your kidney function. High eGFR is normal in pregnancy. Check your creatinine marker for more information. Check your creatinine marker for more lifestyle and supplement suggestions."
Creatinine
Also known as:
Creatinine, Serum
This test measures the levels of creatinine in the blood.
Creatinine is a waste product created from the normal wear and tear of muscles [
R]. It is produced from creatine, a protein needed to generate the energy for muscle contractions [
R]. Its production essentially reflects lean body mass, and because this mass changes little from day to day,the production rate is also fairly constant. Women, children, and older people tend to have lower levels of creatinine compared to adult men because they have less muscle mass [
R].
Creatinine is removed from the body by the kidneys, which filter almost all of it from the blood into the urine. That is why blood levels are usually a good indicator of how well your kidneysare working [
R,
R]. The creatinine level can be tested as a part of your basic metabolic panel (BMP) or your comprehensive metabolicpanel (CMP).
Range
mg/dL
Low < 0.59
Sub-Optimal 0.6 - 0.69
Optimal 0.7 - 0.9
Supra-optimal 0.91 - 1.2
High > 1.21
Optimal
Your creatinine is within the optimal range! Your kidneys function well, and are able to remove toxins efficiently!
Low
Your creatinine is low.
Low creatinine levels are not always a concern. They often just indicate a diet low in protein [
R].
However, low creatinine can also be caused by:
Malnutrition [
R]
Muscle wasting (in illness or aging) [
R,
R,
R]
Extreme weight loss [
R,
R]
Liver disorders [
R]
Limb amputation (lower is normal) [
R]
Pregnancy (lower is normal) [
R]
Low creatinine increase your all-cause mortality risk and the risk of diabetes [
R,
R].
If low creatinine is caused by an underlying disease, seek medical treatment.
Adjust your diet! Make sure you are well nourished and your diet contains enough protein.
Increase physical activity - exercise increases creatinine levels + it helps build muscle [
R,
R].
Avoid alcohol. It may decrease blood creatinine [
R,
R]
Supplements that can help:
Protein supplements
Creatine
High
Your creatinine levels are high!
As the kidneys become impaired for any reason, they can’t efficiently filter out waste products and toxins anymore. As a result, creatinine levels in the blood will rise.
A high creatinine increases your all-cause mortality risk [
R].
High creatinine can be caused by:
Dehydration [
R]
A diet high in protein [
R,
R]
Cooked meat. This happens because cooking converts the creatine present in meat (which is muscle) into creatinine [
R,
R]
Vigorous exercise [
R,
R]
Creatine supplements [
R]
Kidney disorders/diseases [
R,
R]
Hypothyroidism [
R]
Some drugs also cause high creatinine levels:
Antibiotics such as trimethoprim/sulfamethoxazole (Bactrim, Cotrim, Septra) and cefoxitin (Mefoxin) [
R]
Histamine H2 receptor blockers that inhibit stomach acid production: cimetidine (Tagamet), famotidine (Pepcid), and ranitidine(Zantac) [
R]
NSAIDs such as indomethacin (Indocid, Indocin) and ibuprofen [
R,
R,
R]
Anticonvulsants such as phenacemide (Phenurone) [
R]
Acetaminophen (Tylenol, Panadol, paracetamol) [
R]
A high level of creatinine will not cause symptoms on its own. Even if you have above-normal levels you may notice no change. However, high creatinine is often caused by an underlyingdisease that affects kidney function, such as kidney disease, diabetes, high blood pressure, or hypothyroidism. In these cases, you will experience the symptoms of the underlying disease/disorder.
Seek treatment for any underlying disease!
Avoid creatine and creatine-based supplements.
Increase fluid intake, try to drink at least two liters of water a day! High blood creatinine may be a result of dehydration [
R].
Increase dietary fiber! It improves kidney health and can lower blood creatinine levels [
R]. Fruits, veggies, whole grains and legumes are good sources of fiber.
Lower your protein intake - kidneys must work harder when there’s more protein in the diet. A high-protein diet can further aggravate kidney function [
R].
Limit potassium - if creatinine is high, that means that potassium is not filtered well either, and you may be at risk of having elevated potassium levels [
R]. Decrease potassium-rich foods such as avocados, bananas, prunes, potatoes, spinach, tomatoes, beans, and brown rice.
Decrease phosphorus containing foods such as soft drinks, artificial sweeteners, snack foods, and processed foods. If creatinine is not filtered efficiently, neither is phosphorus,and the levels may increase above optimum [
R].
Avoid strenuous exercise [
R,
R].
Lose some weight if overweight. Weight loss can increase your kidney health and decrease creatinine levels [
R].
Supplements that can help and are beneficial for kidney function:
Alpha lipoic acid [
R,
R]
Salvia miltiorrhiza (red sage) [
R]
Nettle (
Urtica dioica) [
R]
Astragalus [
R,
R]
Ginseng [
R,
R,
R,
R,
R]
Chamomile [
R]
Spirulina - protects the kidneys [
R,
R,
R]
Chitosan [
R]
