Does Drinking More Water Protect The Kidneys Or Hurt Them?
Mar 23, 2023
Water is an important part of the human body
Water is the most important substance that makes up the human body. When the fetus is conceived in the amniotic fluid of the mother, water accounts for 90% of the body weight, 80% in the neonatal period, 70% in early childhood, 60% in males, and 55% in females after adulthood -50%. With age, the proportion of body water to body weight decreases.
Click to Check what is Cistanche used for kidney disease
Water is the solvent of all nutrients and metabolic substances, directly mediating the digestion, absorption, transport, metabolism, and excretion of the nutrients we ingest; water also maintains the activity of various enzymes in the body, promotes various biological activities and biochemical reactions, Participate in oxidation-reduction reactions, water also regulates body temperature, and water also acts as a lubricant, such as tears, saliva, body fluids in the joint cavity, and so on.
How much water do people need every day?
Adults generally need about 3000 ml of water per day.
The main sources of water in the body are:
Drink 1500~2000ml of water directly every day (recommended by the Chinese Nutrition Society: drink at least 1500~1700ml of water every day);
Water in food, about 750ml;
The water generated by oxidation in the body (also called metabolic water, is the water generated by the oxidation of sugar, fat, and protein in the body. Every 100 grams of sugar can produce 55 ml of water when oxidized, and every 100 grams of fat can produce 107 ml of water. Every 100 grams of protein Can produce 41 ml of water. The metabolic water produced in the human body is about 300 ml every day).
The water intake and excretion of the human body are balanced. The ways of water excretion of the human body are urine 1500-1800 ml, stool about 150 ml, respiration about 400 ml, and skin 500-800 ml. If you get hot and sweat, more water will be lost through the skin.
Kidneys and water
The kidney is the organ with the most abundant blood flow in the whole body. Its main function is to excrete metabolic waste and maintain the body's water, electrolyte, acid-base balance, and internal environment stability. Normal people have 1000~1200ml of blood flowing through the kidneys every minute, accounting for 20%-25% of cardiac output. 20% of the plasma (accounting for 55% of the blood) flowing through the kidneys is filtered by the glomerulus into primary urine. The glomerulus is filtered to produce about 180L of primary urine every day, and after a series of treatments such as concentration and dilution of the renal tubules, about 1.8L of urine is finally formed. That is, 99% of the fluid filtered out by the glomerulus is reabsorbed, and only 1% is excreted.
Adult urine output is about 1800ml per day:
Urine output <400mL/d is oliguria;
Urine output <100ml/d is anuria
Urine output >2500ml/d is polyuria
Urine volume>4000ml/d is diabetes insipidus
Under normal circumstances, the ratio of daytime urine output to nighttime urine output is about 2:1. If the nighttime urine output is more than the daytime urine output or the urine output is greater than 750ml every night during sleep, it is called nocturia.
Urine output is affected by many factors, such as how much you drink, how much you sweat, and the state of your kidney function. Drinking less water and sweating more will lead to decreased urine output. On the contrary, if you drink more water and sweat less, you will urinate more. If you drink a lot of water, don't urinate much, or even experience edema in your lower limbs and face, you may have kidney disease.
Humans produce about 600mOsm of metabolic waste every day, even if they use the most concentrated urine to excrete, at least 500ml of "necessary urine volume" is required. A urine output of less than 500ml means that the kidneys cannot complete the task of excreting metabolic waste that day. Therefore, the daily urine output should be at least 500ml or more.
Patients with renal insufficiency have poor urine concentration function, and the usual urine output is not enough to eliminate the metabolic waste produced by the body every day, so an appropriate increase in urine output is required.
Should kidney patients drink more water or less water? The general principle is "according to need" and "according to output", the amount of drinking water is mainly determined according to the needs of the body and the amount of urine. Drink more water when the body is dehydrated (dehydration); drink less water when the body is dehydrated (edema). Under normal circumstances, the daily water intake is urine output + 500ml. If you drink a lot of soup or gruel, drink less water.
Comparison of water consumption in different types of kidney disease
Of course, patients with kidney disease drink different amounts of water according to their general conditions, different types of kidney disease, renal function status, and cardiac function status.
1. For patients with insufficient blood volume such as oliguria (strong tea-like), low blood pressure, and rapid heart rate due to reasons such as drinking less water, fever, excessive sweating, and diarrhea, it is necessary to drink plenty of water and strive to maintain daily The urine output is about 1800ml.
2. If patients with iodine contrast, crush syndrome, rhabdomyolysis, and multiple myeloma cast nephropathy need active hydration, they should quickly drink a lot of water or rehydration, and supplement sodium appropriately, and strive to achieve a urine output of 2500ml per day. Promote the rapid excretion of myoglobin, light chains, and contrast agents from the body.
3. For patients with urinary tract infection, urinary tract stones, and hyperuricemia, after taking sulfa drugs, mild to moderate renal insufficiency combined with azotemia and no edema, drink plenty of water and keep the daily urine output at About 2500ml, to promote the excretion of urinary tract bacteria, small stones, uric acid crystals, drug crystals, and nitrogenous substances, and maintain renal function at a stable level.
4. For patients with renal disease with normal hematuria, proteinuria, and normal renal function, treat them as normal people. The daily water intake is about 2000ml, and the daily urine output is kept at about 1800ml.
5. For patients with nephrotic syndrome (including minimal change, membranous nephropathy, focal segmental glomerulosclerosis, diabetic nephropathy, renal amyloidosis, etc.) Eat less salt (sodium chloride) and drink less water. If necessary, diuretics are also used for diuresis and to reduce swelling. The amount of water intake should be less than the output, and strive to lose about 0.25kg (half a catty) of body weight every day until the swelling subsides.
6. For dialysis patients with oliguria in acute renal failure, decreased urine output in the late stage of chronic renal failure, and anuria, as well as patients with liver cirrhosis, massive ascites, congestive heart failure, breathlessness, and inability to lie supine at night, strict "measurement is required" ", strictly limit the intake of salt and water, and ensure that the weight gain between dialysis is within the allowable range. The daily weight gain should not exceed 0.5% of the body weight (within half a catty to 1 catty), and the weight gain during the two dialysis periods should not exceed dry. 3-5% of body weight (within 2-3 patties), to ensure the effect of dialysis.
If you drink too much water between two dialysis sessions, it will cause much harm due to long-term excessive water load:
High blood pressure, and cerebrovascular events: If a dialysis patient drinks too much water, the blood volume of the body will increase, and the blood vessels will be excessively congested and dilated. Elevated, may manifest as nausea, dizziness, and other symptoms. Discomforts such as dizziness and headache will also increase the risk of cerebrovascular accidents.
Left heart failure: If a dialysis patient drinks too much water, it will cause an increase in blood volume, which will increase the load on the heart. After the excess blood enters the heart, it will cause greater pressure on the heart. If the pressure exceeds the capacity of the heart, cardiac insufficiency, and acute heart failure are prone to occur, which may manifest as symptoms such as rapid heart rate and dyspnea, accompanied by fatigue and emotional anxiety. Coughing, expectoration, dyspnea, inability to lie down, and death can occur in severe cases.
Edema: Including face, limbs, and even pulmonary edema, fatigue, and difficulty breathing. During the next dialysis, due to excreting too much water, will cause hypotension, muscle cramps, and pain during dialysis.
In general, water is very important for the human body and the kidneys. Drinking less water will affect the excretion of metabolic waste, and dehydration will aggravate kidney damage. It is very important to drink enough water every day to maintain normal urine output. If you have edema and heart failure, you should drink less water. Patients with uremia and dialysis should strictly control their water intake.
Why eating Cistanche is good for kidney disease
Cistanche is a type of herb commonly used in traditional Chinese medicine. It has been suggested to have a protective effect on kidney function and may have potential benefits for those with kidney disease. One study published in the Journal of Ethnopharmacology found that cistanche had a renal protective effect in rats with kidney damage caused by diabetes. The study showed that cistanche helped to reduce the levels of creatinine and blood urea nitrogen (BUN), which are markers of kidney function. Additionally, it was found that cistanche helped to prevent oxidative damage and inflammation in the kidneys. Another study published in the Journal of Medicinal Food looked at the protective effects of cistanche on kidney function in rats with liver damage. The study found that cistanche helped to improve kidney function by reducing oxidative stress, inflammation, and fibrogenesis. Overall, while more research is needed in humans, studies suggest that cistanche has the potential as a natural supplement to support kidney function.
Reference:
- Chinese Herbal Medicine for the Management of Chronic Kidney Disease: An Overview of Systematic Reviews; Yu-Feng Qin, Jiang-Hua Chen, Ming-Hua Guo, Dan-Dan Liu, Ling-Li Zhang; Evidence-Based Complementary and Alternative Medicine; Volume 2018, Article ID 8094231, 14 pages.
- Curative effect of Cistanche tubulosa aqueous extract against diabetic renal damage and the underlying mechanisms; Qian L, Ma X, Jiang N, Wang Y, Jiang Y, Zhou Y, Xu R; J Ethnopharmacol. 2016 Jan 11;177:113-9.
