High blood pressure is a condition where the force of blood pumping is elevated, thus causing excess stress on the walls of the veins. Left untreated, high blood pressure often leads to hypertension, stroke, or heart attacks.
Unfortunately, high blood pressure does not derive from just one underlying factor. Many lifestyle decisions affect blood pressure, including hydration levels and diet. Let’s take a closer look between hydration (or more specifically, dehydration) and elevated blood pressure; and when to see your doctor.
Over half of the body is made up of water, so hydration levels affect many aspect of health. A well-hydrated body is a well-lubricated body — everything flows better and easier when hydration is prioritized.
Dehydration occurs when the body does not receive enough water. Heavy sweating can easily lead to dehydration, as can failing to drink any water upon waking. Sicknesses like vomiting and diarrhea can also lead to dehydration.
How does hydration affect blood pressure?
Dehydration will cause your blood volume to decrease. Blood volume refers to the amount of fluid in your blood vessels, and volume is important to maintain because it allows your blood to reach all the tissues and organs in your body. Lowered blood volume can cause your blood pressure to drop.
Therefore, dehydration can cause your blood pressure to drop, which is called hypotension (as opposed to hypertension, which signals elevated blood pressure). When blood pressure drops below normal levels, organs and other extremity tissue are deprived of oxygen and nutrients.
“When left untreated, low blood pressure can cause other issues, like heart and/or brain damage,” Dr. Jason Varghese points out.
Alternatively, dehydration can sometimes lead to high blood pressure in some patients. When your body is dehydrated, it releases higher amounts of a chemical called vasopressin, which helps the kidneys retain water. Vasopressin is meant to prevent you from losing more water through urination during times the body is under immense stress. The chemical also causes the blood vessels to constrict, which then causes blood pressure to increase. Too much vasopressin in the body almost certainly leads to high blood pressure.
How much water should you drink to avoid dehydration?
The body doesn’t need nearly as much water as it would like to have. Most doctors suggest drinking about eight glasses of water a day for optimal hydration. Many health and wellness experts like to try to drink one gallon of water per day, and they’ll use the color of their urination as a sign of how well they’re doing (clear pee means you’re doing great).
“The ‘correct’ amount of water you should be drinking every day can vary per person. It depends on numerous factors such as your weight, physical activity level, etc.,” Dr. Varghese explains.
If you’re unsure how much water to drink, ask your doctor. Your doctor can review your medical history, talk to you about your lifestyle, and make the best recommendation based on this information. But drinking water has almost zero downside and virtually unlimited upside, so best to err on “too much” water rather than not enough. You’ll notice a difference in how you feel almost immediately, especially if you’re engaging in an activity that makes you sweat or physically exhausts you. Plus, your blood pressure has a better chance of stabilizing with proper hydration and nutritional choices.