Can dehydration affect your kidneys? The answer is yes.
About 60-70% of your body weight is made up of water, and every part of your body needs it to function properly. Dehydration happens when you lose an excess amount of this important body water. This water loss can happen because of diarrhea, vomiting, sweating, or extra losses in your urine, such as poorly controlled diabetes.
Water helps remove wastes from your blood in the form of urine. Water also helps keep your blood vessels open so that blood with important nutrients can travel freely to your kidneys. But if you become dehydrated, then it’s harder for this delivery system to work. Mild dehydration can make you feel tired, and it can also impair normal body functions. Severe dehydration can lead to kidney damage, so it’s important to drink enough when you work or exercise very hard, and especially in warm and humid weather. Some studies have shown that frequent dehydration, even if it’s mild, may lead to permanent kidney damage.
Dehydration can cause a build-up of wastes and acids in the body, and it can clog the kidneys with muscle proteins (myoglobin). All these things can hurt the kidneys. Dehydration can also contribute to the formation of kidney stones and urinary tract infections, both of which can lead to kidney damage if not treated quickly. Kidney stones form less easily when you have enough water to prevent stone-forming crystals from sticking together. Water helps dissolve antibiotics used for urinary tract infections, thus making them more effective. Water also helps you make more urine to flush out germs.
You can get a rough idea about how well you’re hydrated by looking at your urine. If it’s a very dark yellow, that may mean you may need more water. But if it’s always very dark, then you should check with your healthcare professional to see if something like a certain drug is changing the color of your urine, and not your hydration status. There is no set rule about the amount of water everyone should drink. We all have different needs for water depending on differences in age, climate, exercise intensity, as well as states of pregnancy, breastfeeding, and illness. If you have kidney failure, or low kidney function, then you may need to restrict your water and fluid intake. All questions and concerns about dehydration and water intake should be discussed with your healthcare professional.