Urinalysis is frequently used to screen for urinary tract infections (UTIs), kidney and liver issues, and diabetes. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. The bilirubin test is one of a comprehensive panel of liver function tests that measure different liver products in your blood. However, too much can be toxic. Put the cap on the container and return it as instructed. Ketones are by-products of fat breakdown in the body. Place the strip against the blood and leave it there until the meter registers. High amounts of ketones in the urine is what is known as ketonuria. You may opt-out of email communications at any time by clicking on A urinary pH close to 8 reflects a more alkaline urine. These abnormal results are usually transient, meaning they will go away once the infection is treated. What are the causes of urine ketones? Before the infant is born, there are various forms of haemoglobin in the body. A bilirubin blood test measures bilirubin levels in your blood. Why examine the urine sediment? The moment an infant is born, the old haemoglobin breaks rapidly, which leads to a high level of bilirubin. Urine . Seattle (WA). Most of the time, hyperbilirubinemia in newborns is predictable and self-limited. It is a by-product of the breakdown of red blood cells. If it builds up in your blood, it can make you feel ill. I just got a call though that my culture came back clear, so it's not a UTI. You are not required to obtain permission to distribute this article, provided that you credit the author and journal. Fatigue or general weakness. When found in the urine during pregnancy indicates that there are not enough calories at regular intervals during the day or it could mean that the blood glucose is too high. A bilirubin in urine test is often part of a urinalysis, a test that measures different cells, chemicals, and other substances in your urine (pee). Jaundice becomes visible when your bilirubin levels are two to three times the normal range. How long does Adderall, THC, Molly, Opiates and Nicotine stay in your system ? Too little urobilinogen can indicate liver dysfunction, too much may indicate liver disease such as cirrhosis or hepatitis. Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. Bilirubin and urobilinogen are byproducts of the normal breakdown of red blood cells. An antiviral medication is used to treat high level of bilirubin of viral origin. A bilirubin in urine test is only one measure of your liver health. Travel history would give the clinician insight into whether the patient has been into hepatitis endemic regions. This part only takes a few minutes. Review article: quantitative tests of liver function. At these levels, unconjugated bilirubin exceeds the amount of available albumin to bind it. A healthcare provider may also order a bilirubin urine test specifically if you have visible jaundice or dark-colored urine. 2. Krishna RP, Lal R, Sikora SS, Yachha SK, Pal L. Unusual causes of extrahepatic biliary obstruction in children: a case series with review of literature. Chen M, Suzuki A, Borlak J, Andrade RJ, Lucena MI. Jaundice is often the first symptom that would prompt a healthcare provider to check your bilirubin levels. Your test will show these values separately, as well as your total bilirubin. While I was there, the optician asked if I or anyone in my family had diabetes. Can diet help improve depression symptoms? Ketones are essential to maintaining a healthy body. Blood in your urine requires additional testing. The light helps break down the bilirubin into a water-soluble form so that the body can excrete it without conjugating it in the liver. Bilirubin chemistry and metabolism; harmful and protective aspects. Your body makes. A Word of Caution "Urobilinogen and etodolac [arthritis drug] may cause false-positive . Mast EE, Alter MJ, Margolis HS. Urinalysis; [cited 2022 Mar 13]; [about 1 screens]. You can learn more about how we ensure our content is accurate and current by reading our. Ketones are chemicals produced by the liver that increase whenever glucose (blood sugar) levels are low. Urinate into the toilet for a few seconds and then stop the flow. However, they can include ongoing nausea, fatigue, or difficulty breathing. Evaluation of the urinalysis results with other tests can help your provider determine next steps. Available from: Saint Francis Health System [Internet]. Newborn jaundice is common and usually nothing to worry about, but very high bilirubin levels in newborns can be toxic. Use a lancet to prick your finger. Most urobilinogen is excreted in the feces (90%). Click here for an email preview. Bilirubin is a yellowish to brownish pigment found in the bile and produced by the liver. Urinate at least 1 to 2 ounces (30 to 60 milliliters) into the collection container. Open the container without touching the inside. Make a donation. The treatment of bilirubinuria is targeted towards thedifferent clinical etiologies responsible for the laboratory abnormality. Note: Only conjugated bilirubin can be excreted as bilirubinuria. Several proteins can be found in the urine, but the most relevant to kidney disease is albumin. It is often used to help find and diagnose liver disease. someone on a severe weight reduction diet where the body is starving, and there isn't enough available glucose and fat will burn for energy and the by product of that are ketones. Bilirubin is a yellow substance that your body makes during the normal process of breaking down red blood cells. Ketones are most common in people who do not consume enough carbohydrates. Creeden JF, Gordon DM, Stec DE, Hinds TD Jr. Merck Manual Professional Version. Wash your hands with soap and water and dry them. Urobilinogen is a by-product of bilirubin, which is a yellow compound processed by. Not eating meals on time or taking long gaps between meals. Social history with a special focus on alcohol consumption should be sought as they may contribute to hepatic dysfunction. [Level 5], Evaluation of bilirubinuria (updated). If it is bacterial in origin, the doctor will prescribe antibiotics. Abnormal amounts of bilirubin in the urine are associated with liver disease or red blood cell destruction (called hemolysis), and should always be investigated. Page K, Morris MD, Hahn JA, Maher L, Prins M. Injection drug use and hepatitis C virus infection in young adult injectors: using evidence to inform comprehensive prevention. Bilirubin is a byproduct of broken-down old red blood cells. A urinalysis may be performed during a routine check-up, to evaluate certain . [1], With a wide range of etiologies for bilirubinuria, an entire interprofessional team must work hand in hand to ensure the best outcomes for the patient. Available from: Testing.com [Internet]. . Ketones in the urine are usually the result of a glucose deficiency and may lead to DKA. The lab will measure your bilirubin levels to determine whether theyre in the normal range. Access free multiple choice questions on this topic. A complete urinalysis evaluates several different aspects of your urine through physical, chemical, and microscopic examination. For specifics about what your urinalysis results mean, talk with your health care provider. False positives can be associated with highly colored substances that can mask the results such as phenazopyridine, indicans, chlorpromazine, or etodolac metabolites which cause reddish discoloration of urine. When your liver processes the bilirubin, it unbinds it from the albumin and binds it to a sugar molecule, making it water-soluble. This causes the level of bilirubin in the blood to rise. The information on this site should not be used as a substitute for professional medical care or advice. However, an abnormal or high result could be due to other factors such as: If a person is unsure of their results, they should contact a healthcare professional to interpret the results, especially for at-home testing. For adults, hyperbilirubinemia might signal a dangerous condition, but the bilirubin itself isnt dangerous. Usually, glucose, ketones, protein, and bilirubin are not detectable in urine. Around 5% is transported back to the liver and re-secreted into bile again. Don't let the container touch your body. stress, pregnancy, and other factors can cause a temporary rise in urine protein levels. A: A urinary tract infection causes a significant amount of irritation in the bladder and can cause the urine dipstick to show protein, red blood cells and white blood cells. other information we have about you. This allows it to mix with bile and pass through your intestines. It may suggest a problem that needs attention. It may even show up before you have symptoms. The urine sample is sent to a lab for analysis. While having low or moderate amounts of ketones may result in weight loss, high levels can be dangerous or even fatal. The second one showed blood, bilirubin, and ketones. A dipstick test checks for: Sometimes performed as part of a urinalysis, this test involves viewing drops of concentrated urine urine that's been spun in a machine under a microscope. In general, you can reduce overall stress on your liver by eliminating alcohol and drugs including over-the-counter (OTC) medications, if possible and maintaining a healthy diet. This is often witnessed in case of pregnant ladies, Diabetes type 1 patients and people who starve or fast. MNT is the registered trade mark of Healthline Media. A false-negative test can occur in prolonged cholestasis where despite the presence of conjugated hyperbilirubinemia, the predominant fraction of bilirubin which is covalently bound to albumin, delta bilirubin, will not be filtered by the glomerulus. How to safely use glucose meters and test strips for diabetes. In most people, ketones don't pose a problem. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Photo Source: healthsaline.com, Image 3: A comparison image of a bilirubin test using two different samples: blood and urine. It only becomes alarming when it is accumulated in the bloodstream. (5, 10), Total Parenteral Nutrition (TPN) and Enteral Nutrition. Drug-induced liver injury: Interactions between drug properties and host factors. https://www.uptodate.com/contents/search. The presence of bilirubin or urobilinogen in the urine may indicate abnormally increased breakdown of red blood cells, liver disease or a blockage of bile flow into the intestines. A healthy liver removes most of the bilirubin from your body. Start urinating again, this time into the container. [17], On physical examination, a thorough skin and ocular exam are important to denote the presence of jaundice and scleral icterus. Here is how to conduct an at-home blood test: Always use a sterile, unopened, non-expired test strip and blood glucose meter for accurate, safe testing. Bilirubinuria might be the earliest sign of a pathological process in the liver. Your health care provider may recommend additional urinalysis tests if a high level of protein is found This . Available from: Testing.com [Internet]. Urine bilirubin levels are commonly assessed with the urinalysis dipstick test; this test involves use of a pad that produces a diazotization color reaction in the presence of bilirubin. Check for ketones in the blood and urine via at-home or in-lab testing. Newborns produce bilirubin faster than adults do, and they conjugate it much slower. Consumption of alcohol should be restricted too. Johns Hopkins Medicine; c2022. Bilirubin is conjugated and becomes water-soluble in the liver and is then excreted through the biliary and cystic ducts to either become stored in the gallbladder or pass through the duodenum. False positives can be associated with highly colored substances that can mask the results such as phenazopyridine, indicans, chlorpromazine, or etodolac metabolites which cause reddish discoloration of urine.[21]. Elevated urinary bilirubin occurs in patients with obstructive jaundice or jaundice due to hepatocellular disease or injury. Skipping snacks or meals during pregnancy. Starvation Starvation ketones are formed since the body uses fat reserves instead of carbohydrates to obtain energy. The results are typically listed as small, moderate, or large as follows: Small: <20 mg/dL. The test may also be ordered if you have symptoms of a liver condition, gallbladder disease, or a problem with your bile ducts (the small tubes that carry bile out of your liver). A normal healthy body can pass out the body during the digestive process. To understand the presence of bilirubin in the urine, it is important to understand the physiology behind bilirubin metabolism which can be divided into three phases: prehepatic, hepatic, and posthepatic.[11][12][13]. This is especially so in people with type 1 diabetes. If there is hepatocellular dysfunction or biliaryobstruction, some of the direct conjugated bilirubinescapes into the bloodstream, gets filtered by the kidneys, and excreted in the urine. Cleanse the urinary opening. http://creativecommons.org/licenses/by-nc-nd/4.0/. It can also help diagnose liver problems and many other medical conditions. When red blood cells finish their life cycles in your body, they break down and pass through your bloodstream to your liver for processing. Advertising on our site helps support our mission. Dhatariya, K. (2017). Review the management options available for bilirubinuria. You might have a higher total bilirubin count if something is temporarily stressing your liver, such as a new medicine or a high dose of alcohol. They may suggest further blood tests or imaging tests to help diagnose your condition. Symptoms that may accompany higher than normal levels of bilirubin in urine may include: Yellowing of the skin and whites of the eyes. This condition is usually a sign of diabetic ketoacidosis (DKA). What to know about urine tests for creatinine, Debra Rose Wilson, Ph.D., MSN, R.N., IBCLC, AHN-BC, CHT. False negatives can be associated with urinary nitrates, acidic urine with a pH below 5.5, antibiotic use, which decreases the intestinal flora, oxidation by vitamin C, (as bilirubin will not react with the diazonium salts). Its presence is abnormal and can be the first clinical pointer of serious underlying hepatobiliary disorder even before clinical jaundice is appreciated. This site complies with the HONcode standard for trustworthy health information: verify here. Once in the hepatocyte, the unconjugated bilirubin is taken to the endoplasmic reticulum, where it is conjugated with a sugar via the enzyme glucuronosyltransferase and is then soluble in the aqueous bile. Best food forward: Are algae the future of sustainable nutrition? We do not endorse non-Cleveland Clinic products or services. Protein in urine can make it appear foamy. Normal levels for newborns can range anywhere between 1.0 and 12.0 mg/dL. 2004-2023 Healthline Media UK Ltd, Brighton, UK, a Red Ventures Company. Gently squeeze your finger to make it bleed. Any use of this site constitutes your agreement to the Terms and Conditions and Privacy Policy linked below. All brands of reagent strips can detect the following ketones: acetoacetic acid, diacetic acid. Visible jaundice (yellowing of your skin and eyes) is a sure sign to see a healthcare provider for a bilirubin test. A single copy of these materials may be reprinted for noncommercial personal use only. Its presence is abnormal and can be the first clinical pointer of serious underlying hepatobiliary disorder even before clinical jaundice is appreciated. In a normal physiological state,conjugated bilirubin is notpassed in urine. (4). What could small amounts of leukocytes, ketones, and protein in urine indicate? The level of bilirubin is affected by the age and general health condition of the patient. But, it has been in found that in certain cases where the levels of Bilirubin in urine is high, it might be an inherited condition. An abnormal result means you have ketones in your urine. Summary According to the Centers for Disease Control and Prevention, people who have low insulin levels and high blood sugar are most likely to have a buildup of ketones, which develops into diabetic ketoacidosis. High or low bilirubin levels might indicate that some part of the process of breaking down and clearing old red blood cells isnt working correctly. Bilirubin appears in the urine if there is an increase in the serum concentration. Collect at least an ounce or two of urine into the container. Bilirubin-Protein - Urobilinogen-Glucose - Nitrite-Ketones - leukocytes -Blood - Specific Gravity. Bilirubin and related breakdown metabolites are well known for causing the characteristic coloring in bile and stool; however, its presence in the urine is not normal, and for it to be present there, it must be water-soluble and excreted by the kidney. You don't need any special preparations to test for bilirubin in urine. Bilirubin in urine (bilirubinuria) isnt normal, but it might happen when your conjugated bilirubin levels are very high. Unusual urinalysis results often require more testing to find the source of the problem. A liver panel is a group of blood tests that measures many different enzymes, proteins, and other substances in the liver. While preparing for the test, certain medications and supplements should be avoided. You may have a bilirubin urine test as part of a comprehensive urinalysis, a panel of tests that analyze the content of your urine. This activity reviews the evaluation and management of patients presenting with bilirubinuria and highlights the interprofessional team approach in evaluating and treating this condition. Most people with kidney lupus (lupus nephritis) will have an abnormal urinalysis. In fact, both fat and protein consist mainly of ketones. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. This condition is called hemolytic anemia. For a vagina, separate the labia (the folds of skin around the vagina) and wipe the inner sides from front to back. High ketone levels can be dangerous, and may lead to ketoacidosis. Shin SJ, Park H, Sung YN, Yoo C, Hwang DW, Park JH, Kim KP, Lee SS, Ryoo BY, Seo DW, Kim SC, Hong SM. A urinalysis involves checking the appearance, concentration and content of urine. Alcoholic liver disease (alcoholic steatosis, alcoholic hepatitis, cirrhosis), Cholangitis (bacterial, recurrent pyogenic, primary sclerosing, secondary sclerosing), Extrahepatic malignancy (lymphoma, pancreatic cancer). The meter will beep when the strip has enough blood on it. So, your provider may order a bilirubin in urine test if you have a high risk for liver damage or disease because of: You will need to give a urine sample for the test. Urine ketones were confirmed with Acetest and bilirubin was confirmed with Ictotest (Bayer Corp, Elkhart, Indiana). More answers below http://creativecommons.org/licenses/by-nc-nd/4.0/ Vtek L, Ostrow JD. The causes of high levels of ketones and therefore urine ketones include: Poorly controlled diabetes. Lifestyle change is highly recommended in patients with increased level of bilirubin. Drink lots of water and avoid strenuous activity as it can worsen the condition. privacy practices. Ketones or ketone bodies are types of acids. Persistently elevated l. Read More Popular treatments include insulin therapy, fluid replacement treatment, and electrolytes replacement. However, bilirubinuria can also be present in patients with acute liver and biliary disease. Some at-home urine tests, that you buy without a prescription, may measure bilirubin in urine. Liver Panel; [modified 2021 Nov 9; cited 2022 Mar 15]; [about 13 screens]. Bilirubin: This is a normal substance made by the liver from the breakdown of red blood cells. An interprofessional team approach will always be the optimal approach to yield the best possible outcomes. Normally, bilirubin is carried in the blood and passes into your liver, where it's removed and becomes part of bile. health information, we will treat all of that information as protected health Let your finger dry for 30 seconds. What to know about 24-hour cortisol urine tests, Debra Sullivan, Ph.D., MSN, R.N., CNE, COI. The bilirubin released from the reticuloendothelial system that reaches the hepatocyte is unconjugated/insoluble and is bound to albumin. Healthcare providers recommend treatment for newborns when bilirubin levels rise above 15 mg/dL in the first 48 hours or 20 mg/dL after 72 hours. (2019). Unconjugated bilirubin is water insoluble and cannot pass through the glomerulus; conjugated bilirubin is water soluble and. All rights reserved. Diabetic ketoacidosis: Evaluation and treatment. The container should have markings to show how much urine is needed. Theyll insert a hollow needle and draw out a small sample into a vial. You might collect a urine sample at home or at your health care provider's office. In: Carstens E, Akiyama T, editors. Create a dietary plan that includes carbohydrates to increase glucose levels. Holmes I, Berman N, Domingues V. Acute Renal Failure and Jaundice without Methemoglobinemia in a Patient with Phenazopyridine Overdose: Case Report and Review of the Literature. An active baby can move the bag causing urine to go into the diaper. It can also help diagnose liver problems and many other medical conditions. A little bit of protein in the urine can be present in a urinary tract infection, but bilirubin can mean liver problems or hemolysis of red blood cells. The conjugated bilirubin is then excreted into bile. A doctor will often conduct this test in a lab. What is the latest research on the form of cancer Jimmy Carter has? Westerberg, D. (2013). DKA is a severe complication of diabetes that can damage vital organs. Case managers and social workers will help patients with substance addiction to join the services needed and become better. These chemicals are not normally found in urine. Small amounts of ketones in your morning urine can result from eating . Bilirubin may have been oxidized to biliverdin, bottle of . Touch the end of test strip to the drop of blood. New York: American Liver Foundation; c2017. A lab technician examines the urine's appearance. Contact a health care provider if you have questions about your health. Your liver sorts bilirubin with other waste products into a fluid called bile. no blood, nitrites, ketones, bilirubin. DKA is a potentially life-threatening condition, as well as one of the first signs that a person has diabetes prior to diagnosis. In the intestines, the bilirubin gets metabolized by the colonic bacteria into urobilinogen, eighty percent of which gets excreted into feces as stercobilin, given its unique color. Pregnancy symptoms like severe vomiting. Ketones in urine pregnancy are very common. Bilirubin is a yellowish substance in your blood. If any of the following levels are above average, you might need more tests: A urinalysis alone usually doesn't provide a definite diagnosis. Check out these best-sellers and special offers on books and newsletters from Mayo Clinic Press. This is done with a combination of diet, exercise, and sometimes insulin treatment. Contributed by Gilles Hoilat, MBBS. DKA is a severe complication of diabetes that can damage. Youll get these results back later. The treatment of gestational diabetes is aimed at keeping your blood sugar under control. It is a process in which the stone is destroyed via a series of ultrasound treatment. Your health care provider may have ordered a bilirubin in urine test as part of your regular checkup. Available from: Mayo Clinic [Internet]. However, if the stone is quite big, the best approach is lithotripsy. It deels with the function of the liver. You might feel a quick prick or sting when the needle goes in or out. This content does not have an English version. If the bilirubin gets out of control, it could lead to jaundice (yellowish discoloration of the skin), which could be an indicator of a liver disease. A bilirubin test can help confirm your providers suspicions of certain types of diseases and narrow down the cause. A portion of it is absorbed back into the blood (around 10%). There is no known risk to having a urinalysis or a bilirubin in urine test. On the other hand, conjugated bilirubin is water-soluble and thus can be renally excreted and detected in the urine. There is a problem with A bilirubin urine test strips are readily available over the counter and can be purchased even without the doctors prescription. Only conjugated bilirubin (water soluble) may be passed into urine in pathologic states. Evaluation of the renal patient. When Bilirubin is traced in the urine, it indicates that there are problems with your liver or the gallbladder. Heart failure: Could a low sodium diet sometimes do more harm than good? If your levels are higher, your healthcare provider may want to investigate further to look for the cause. Bile exits your body through your intestines. Bauer M, Press AT, Trauner M. The liver in sepsis: patterns of response and injury. Nothing was done. However, for people with diabetes, an excess of . People with type 1 diabetes should do the following to prevent ketones from building up in the body: By taking these steps and establishing and following an insulin therapy or treatment plan, people who are at higher risk of developing DKA can help prevent or manage it. information and will only use or disclose that information as set forth in our notice of This might indicate a biliary disease or gallstone disease, such as: Conditions that affect your livers ability to process bilirubin will cause high levels of both types to build up in your blood. Available from: Testing.com [Internet]. Bilirubin is not found in the urine of healthy cats but may be found in small quantities in the urine of healthy dogs. High bilirubin in your blood can also leak out in your pee, making it darker. bleach), peroxide contaminants High specific gravity, ascorbic acid, high ketones, improperly stored specimens (i.e. Patients with biliary obstruction might also complain of dark brown urine, light-colored stool, or pruritis. [14]Surgical history should be taken, especially if the patient has an extensive abdominal past surgical history as well as family history is important to see there are any inherited disorders (Dubin-Johnson and Rotor syndrome). Deliver the sample as directed by your health care provider. A urinalysis is a test of your urine. Before a urinalysis, tell your doctor about medications, vitamins or other supplements you take. . Bilirubinuria is the presence of bilirubin in the urine, usually detected while performing a routine urine dipstick test. Abdominal pain. It is estimated that 3.9% to 6.9% of Americans have some form of chronic liver disease. Large: >80 mg/dL. Diaper as usual over the secured bag. Mortel KJ, Wiesner W, Cantisani V, Silverman SG, Ros PR. When the body does not have enough glucose, or when it does not have sufficient insulin to use the glucose, it begins to use fat for energy instead. What causes bilirubin in urine? Failure of conjugated bilirubin to reach the intestines (e.g. If you have large or elevated levels of ketones in your urine, the test will show results of over 80 mg/dl and it is a medical emergency as ketoacidosis is developing quickly. Bilirubin is a product of red blood cell breakdown. Other health concerns related to high levels of ketones in the urine include hyperglycemia, high blood sugar, and organ damage. High levels of ketone in urine may result from uncontrolled diabetes. I've had 3 urine samples done. Ketosis is common in low-carb diets such as the keto or Atkins diet and is not generally cause for concern. Foley KF, Wasserman J. For the test, a healthcare provider will give you a small container to a collect a sample of your urine in. This depends on the condition. Other reasons why a person may develop ketoacidosis include: DKA is a medical emergency that requires immediate medical care. The conjugated/soluble bilirubin is transported through the biliary and cystic ducts to the gallbladder where it gets stored, or it passes through the ampulla of Vater to enter the duodenum. Acetest confirmed 35 of the 42 ketone-positive samples as ketone positive ( Table ). Your liver uses bilirubin to make bile, a fluid that helps you digest food. Bilirubin is not a bad thing. Certain medications can lower your bilirubin levels, including antibiotics, birth control pills, sleeping pills and seizure medications. Low levels arent generally a cause for concern. This results in the production of ketones. Usual and unusual causes of extrahepatic cholestasis: assessment with magnetic resonance cholangiography and fast MRI. You might have higher levels of unconjugated (indirect) bilirubin if your body is breaking down red blood cells faster than your liver can keep up with. How Viagra became a new 'tool' for young men, Ankylosing Spondylitis Pain: Fact or Fiction, Causes and risk factors for ketones in urine, Centers for Disease Control and Prevention, Treatment and prevention of ketones in urine, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5734222/, https://www.cdc.gov/diabetes/basics/diabetic-ketoacidosis.html, https://www.nhs.uk/conditions/diabetic-ketoacidosis/, https://www.diabetes.org/diabetes/complications/dka-ketoacidosis-ketones, https://www.fda.gov/consumers/consumer-updates/how-safely-use-glucose-meters-and-test-strips-diabetes, https://medlineplus.gov/lab-tests/ketones-in-blood/, https://www.joslin.org/patient-care/diabetes-education/diabetes-learning-center/ketone-testing-0, https://www.ucsfhealth.org/medical-tests/ketones-urine-test, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5922738/, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4944103/, https://www.ncbi.nlm.nih.gov/books/NBK537084/, https://www.cdc.gov/physicalactivity/basics/adults/index.htm, https://www.aafp.org/afp/2013/0301/p337.html.