Keeping Our Kidneys Healthy and Happy
The kidneys exist to maintain fluid balance, regulate function of organs and remove any impurities of metabolism to preserve homeostasis (equilibrium) in our bodies.
The two bean shaped organs that are situated on either side of our spine at the small of the back just above our waist.
To find them place your hands on your hips – the kidneys are just below where the thumbs are located. About the size of our fists, the kidneys weigh approximately 150 grams each.
The kidneys are an extremely efficient waste disposal system. Each day, the kidneys filter 180 litres of blood in a healthy adult, removing about 2 litres of waste and water that our body excretes as urine.
Each kidney contains about 1.0 million filters known as nephrons that balance electrolytes such as sodium and phosphorous in our blood. They are protected from injury by a large padding of fat, our lower ribs and several muscles.
Kidneys and Homeostasis
For such small organs, the kidneys play an enormous and important role in our bodies!
Some of the more important functions of the kidneys are:
- Regulation of pH levels (acid/alkaline).
- Regulation of electrolytes.
- Regulate the amount of fluid in our system (internal water balance).
- Maintain blood pressure – If our blood pressure increases, the kidneys excrete more water and salts so that the volume of blood goes down and our blood pressure decreases. If our blood pressure gets too low, the kidneys decrease the amount of water and salts they excrete so blood volume goes up and blood pressure increases.
- Excretion of wastes and environmental toxins.
- Reabsorption of glucose and amino acids.
- Production of active vitamin D3.
- Help in the production of red blood cells.
- Maintain blood composition.
- Maintain strong and healthy bones and help to keep mineral balance.
The Kidneys – Hormone and Enzyme Factories
The kidneys are crucial hormone and enzyme factories that directly impact on blood, bones and our cardiovascular system.
Three key substances the kidneys control are:
- Erythropoietin (EPO) – When kidney cells sense that the bodys oxygen levels are low, they release more EPO, which stimulates the bone marrow to make more red blood cells to help carry more oxygen to the entire body. If this process is impaired anaemia can result. EPO also plays a role in wound healing and assisting the brain in cases of neuronal injury.
- Calcitriol – The kidneys help regulate levels of calcium and phosphorus which are minerals critical to bone health. The kidneys do this by converting an inactive form of vitamin D, which is produced in the skin and is also present in many foods, to an active form of vitamin D known as calcitriol that acts like a hormone to stimulate absorption of calcium and phosphorus from the small intestine.
- Renin – Renin is not a hormone but an enzyme that eventually produces the hormone angiotensin II. Its role is to regulate the arterial blood pressure by controlling extracellular volume of blood plasma, lymph and interstitial fluid and arterial vasoconstriction. Renin causes the kidneys to retain more water and salt, increasing blood pressure when it drops too low.
How the Kidneys Work
The kidneys remove waste from the blood and eliminate it in urine. This process occurs when blood enters the kidney through the renal artery, blood is then cleaned in the kidney as it passes through tiny filters called nephrons.
There are about one million of these nephrons in each kidney and each nephron contains a filtering apparatus called a glomerulus.
As the filtered blood passes through each nephron, water and waste products are removed. Most of the water returns to the blood via the renal vein, the waste products collect in the bladder and then leave the body as urine.
Kidney Health in Australia 2014 – At a Glance
- Kidney disease has increased by 16% in Australia over the past decade.
- 1 in 3 Australians are at risk of developing kidney disease.
- It is believed that as many as 2 million Australians may have some form of undiagnosed chronic kidney disease.
- 80-90% of cases of chronic kidney disease may go unrecognised/ undiagnosed.
- Chronic kidney disease is the seventh most common cause of death, exceeding diabetes, respiratory disease and suicide.
Chronic Kidney Disease
If someone were to lose over one third of their kidney function for over 3 months this is termed chronic kidney disease (CKD).
A 2006 study published in the Annals of Internal Medicine found that people who are even moderately overweight are seven times more likely to have kidney failure than their thinner counterparts.
Losing as little as 5 kilograms reduces blood pressure in most people who are 10% above a healthy weight. This can assist the kidneys if they are chronically diseased.
Other reasons for CKD include autoimmune disease, taking NSAIDs (non-steroidal anti-inflammatory drugs) for several years and chronic inflammation.
Kidney failure happens for the most part gradually and over many years except in cases of poisoning or there is a physical injury to the kidney area.
Symptoms of the kidneys failing are: fever or chills, swelling of the ankles, puffy eyes, fatigue, weight loss, dark urine, abdominal pain, itching, or pale skin.
In most cases however there are very few symptoms. Cruelly symptoms don’t usually appear until 60 to 70 percent of kidney function is lost.
Kidney failure requires the individual to be under close medical supervision and may require dialysis or a kidney transplant.
Tests Used to Determine Kidney Function and (Possible) Damage
Estimated Glomerular Filtration Rate (eGFR) – This test shows how well our kidneys are cleaning the blood and is the primary test used to determine kidney health.
- eGFR is reported in millilitres per minute per 1.73m2 (mL/min/1.73m2).
- A GFR of 100 mL/min/1.73m2 is in the normal range so it is useful to say that 100 mL/min/1.73m2 is about equal to ‘100% kidney function’.
- A GFR of 50 mL/min/1.73m2 could be called ‘50% kidney function’.
Creatinine – Creatinine is a waste product made by the muscles. Under normal conditions creatinine is removed from the blood by the kidneys and passes out in the urine but when the kidneys aren’t working well, creatinine stays in the blood. Creatinine levels vary with age, gender and body weight so is not an accurate way of measuring overall kidney function. When on dialysis creatinine levels are always high.
Urea – Urea is a waste product that is made as the body breaks down protein. High urea levels suggest decreased kidney function.
Albumin Creatinine Ratio –This urine test is used to measure the amount of albumin (a protein) that leaks into our urine when there is kidney damage.
Urinalysis – An examination of a urine sample to detect medical conditions like kidney disease as well as diabetes and urinary tract infections. This is a visual examination for colour and clearness. A chemically treated strip or dipstick is used to test for pH, sugar (glucose), blood, bacteria or waste products. A urine sample can be sent to a laboratory for an examination under a microscope or to grow a culture if an infection is suspected.
Lifestyle Modifications to Improve Kidney Health
- Stop smoking. The results of a 2007 study published by the American Physiological Society suggest that nicotine is a major factor in the development of kidney disease.
- Control key biomarkers: cholesterol (recommended level is no higher than 5.5 mmol/litres), blood pressure (below 130/90) and blood sugar (normal levels are 4-6 mmol/L before meals and 4-8 mmol/L two-hours after meals).
- Avoid soft drinks (especially ones with high-fructose corn syrup, a known cause of obesity and inflammation).
- Avoid pain medications and any other prescription or over-the-counter medications that may tax the kidneys.
- Stay hydrated. Drink at least eight to ten glasses of water (preferably filtered) every day.
- Cut back on alcohol consumption. Overindulgence can increase blood pressure (a problem for the kidneys) and urination (which can cause dehydration). Heavy drinking can increase blood pressure and contribute to heart disease, which over time may also contribute to kidney disease.
Key Nutrients and Herbs that Assist with Kidney Health
Cleavers – Galium aparine
Cleavers is indicated for improved detoxification and to support urinary waste elimination. An infusion/ tea can be used to stimulate the kidneys, to help the body eliminate excess water, help reduce the impact of cystitis and to expel kidney stones.
Couch grass – Agropyron repens
Couch grass has been used medicinally since about 25 AD. Couch grass increases urine production and treats urinary tract infections such as cystitis and urethritis. Couch grass is believed to relieve and even partially dissolve kidney stones. Additonally Couch grass has diuretic, demulcent and antibacterial properties.
Uva ursi – Arctostaphylos uva-ursi
Uva-ursi is one of the best urinary antiseptics and can enhance the bodies own natural resistance mechanisms helping to resist or address infections. Used extensively in herbal medicine since the 2nd century, uva-ursi is primarily used to help disinfect and tone the kidneys. Uva-ursi also has antibacterial properties. Note: uva-ursi should not be used by pregnant women. While promoting kidney health, uva-ursi should not be used to treat existing kidney infections. Also known as bearberry.
Buchu – Barosma betulina
A strong tea of dried Buchu leaves assists in reducing painful urination and for inflammation, gravel and excessive discharge and inflammation of the bladder.
Dandelion – Taraxacum officinale
Dandelion is a tonic herb, so it feeds, tone, rehabilitate and strengthen the kidneys. Dandelion leaves have a slightly bitter flavor that goes well in salads.
Dandelion leaves contain vitamins A, B-complex, C and D, provides the minerals iron, potassium and zinc. Dandelion has diuretic effects and also replaces potassium that may be lost in the urine.
Dandelion roots have antiviral effects and when combined with the herb uva ursi, which has antibacterial properties, may also help decrease frequency of urinary tract infections in women.
Nettle Leaf – Urtica dioica
Nettle is an anti-inflammatory herb. Nettle can act to increase urinary volume and the loss of water from your body, which can help to wash out bacteria out of the urinary tract.
Nettle is a great diuretic and it can remove excess water from the body through the kidneys. More bacteria, viruses and small calcium crystals can also be flushed out with this increased urinary output. This reduces the impact of conditions like urinary tract infections, kidney infections, kidney inflammation and kidney stones.
People with chronic kidney disease often experience symptoms like swelling in the cheeks, legs, feet, ankles and other parts of the body due to sodium and fluid retention as the impaired kidneys can not remove excessive fluid from the body. Nettle can assist with addressing these symptoms.
Crataeva- Crataeva nurvala
Crataeva is useful in reducing tissue inflammation, reduces bleeding and discharge while supporting healing. Crataeva additionally strengthens membranes in the urinary tract to protect against infections. Best taken as a decoction/tea.
- Cystitis (Urinary Tract Infection)
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