Everything You Need to Know About Dehydration and Electrolytes

Dehydration occurs when your body loses more fluids that it takes in, and the fluid is not replaced. When this happens, your body does not have the fluid it needs to carry out normal functions.

What are the signs of dehydration?

Many times, you may not even know that you are dehydrated, because thirst is not always a reliable indicator. If you feel thirsty, you are already dehydrated.

Early signs of dehydration can include many different kinds of symptoms such as dry mouth, headache, dizziness, cramps, excessive fatigue, and, if you are an athlete, you may also see a drop in your physical performance. As things progress, adults can develop extreme thirst, will urinate less frequently , have dark colored urine and may even become confused.

Anyone can easily become dehydrated if they don’t drink enough water during hot and humid weather, especially if they exercise strenuously. Older adults, infants and children and people with chronic illnesses are also at risk of becoming dehydrated.

What is the best way to prevent dehydration?

Drinking plenty of fluids is the best way to prevent dehydration. In other words, stay hydrated. You should do this if you are ill, are exposed to very hot (or cold) weather, are an athlete or very physically active.

If you are an athlete, start hydrating the day before you engage in strenuous exercise and while you are exercising, replenish your fluids at regular intervals. You should also make sure you continue with replacing fluids as you recover from exercising.

Is water enough?

Drinking water is a good way to stay hydrated. How much water you should drink to maintain adequate hydration depends on a lot of things like your level of activity, the temperature outside, humidity and altitude or elevation. Of course, the hotter the weather, the more fluid you lose through sweating and the more you should be drinking.

Now if you are a serious athlete, a sports drink that contains electrolytes and carbohydrates may be your best choice. Almost every study looking at rehydration has found that water alone is not adequate to rapidly replace lost fluids [1]. A study found that a sports drink containing electrolytes can decrease fatigue, improve running speed ( if you are a runner) and increase mental sharpness.

Drinks with electrolytes give your body the fuel it needs in the right quantities, which can help prevent an upset stomach. A drink such as DayLyte that contains potassium, magnesium, calcium and sodium will provide helpful energy during your workouts. Sodium and potassium for example will help move fluid more quickly into your muscles where it can be used efficiently.

You may be wondering, what exactly are electrolytes, and why are they important?

What are electrolytes ?

Electrolytes are minerals in your blood, plasma, and inside your cells that regulate many important processes such as the amount of water in your body, level of hydration, blood PH (how acid or basic your blood is), muscle actions and nerve impulses, among many others.[2] So you can see that they are critical for your body to function properly.

Let’s review valuable information about the following most common electrolytes.

Name Molecular formula Charge Normal blood levels from testing Sodium Na+ Cation-positive 135 - 145 meq/L Potassium K+ Cation-positive 3.7 - 5.2 meq/L Magnesium Mg++ Cation-positive 1.5-2.5 med/L Calcium Ca++ Cation-positive 8.5-10.2 mg/L Chloride Cl- Anion-negative 96 - 106 meq/L Bicarbonate HCO3- Anion-negative 23 to 30 mEq/L

Why is there a plus or minus sign in the molecular formula?

“Electrolyte” is actually the medical word for ions. Ions are molecules that carry a positive or negative electrical charge. Cells that make up your nerves, heart, and muscles rely on electrolytes to maintain the voltage across their membranes – the covering that surrounds your cells- and carry electrical impulses to other cells.

Sodium

Sodium (Na+) is the major positive ion in extracellular fluid (fluid outside of your cells) and controls the amount of water in your body. It also regulates the acid-base balance (pH) in your blood and the voltage across your cells. Movement of sodium in and out of cells is also critical for the proper functioning of cells in your brain, nervous system and muscles. [3]

Sodium balance is mainly maintained by the actions of a hormone- called aldosterone- that works on the kidneys. When you eat a lot of sodium, aldosterone causes your kidneys to excrete it and, conversely, if your sodium intake is low, aldosterone causes your kidneys to slow or stop excreting sodium. Normally, a small amount of sodium is also lost in the feces and sweat.

Imbalance

Low sodium (hyponatremia) is a low serum sodium relative to the water in our body. You can lose a significant amount of sodium through prolonged and heavy sweating, especially in the heat, which can lead to dehydration. Therefore, replacement of this electrolyte in a well-balanced drink is essential maintaining the normal amount of water in your body (proper hydration). Chronic diarrhea or kidney disease can also lead to hyponatremia.

High sodium (hypernatremia) is a high serum sodium concentration due to a decrease in the amount of water in your body. Some causes of hypernatremia are excessive vomiting, burns, excessive sweating ( if you lose more sodium relative to water), or diseases that can affect the kidneys. Hypernatremia is more common in the very young or elderly. [4]

Foods

One of the most common sources of sodium is table salt (Na+Cl-). Processed and prepackaged foods have the highest sodium content compared to fresh fruits and vegetables. Of course, sodium is contained in many hydration beverages since it is the main ion lost in sweat. Even adding sodium to milk or coconut water increases rehydration. [1]

Health effects

Risks

Eating a diet high in sodium (lots of table salt, prepackaged foods and certain restaurant food) increases your risk of developing hypertension (high blood pressure ) and cardiovascular disease (heart and vascular diseases). Hypertension causes less relaxation of your blood vessels so that your heart has to work harder to pump blood. The higher force of the blood flow damages arteries and other organs such as your kidneys and brain.[5]

Benefits

Sodium and potassium both affect blood pressure. In addition to decreasing your sodium intake, if you eat foods high in potassium, this can help to lower blood pressure by decreasing the bad effects of sodium.

For more helpful information, see Dietary Guidelines for Americans

Potassium

Potassium is the major positive ion located inside of your cells (intracellular). The concentration of potassium inside your cells is 30 times higher than outside. It is important to maintain this ratio to keep your cells functioning normally, and potassium works closely with sodium through a pump in your cell membrane (cell’s covering) to accomplish this. Keeping that ratio steady, also allows the small amount of potassium that is in your circulation to help with the proper transmission of nerve impulses, muscle contractions, and blood pressure control. [3]

Your kidneys are the main regulators of potassium balance. Potassium is mostly lost in the urine though some is also excreted in the gastrointestinal tract. Very little potassium is lost through sweat. [3]

Imbalance

Normally, low potassium (hypokalemia) is due to excess loss and rarely from a deficiency in your diet. You can lose potassium if you have chronic diarrhea, vomiting, and use an excess of laxatives. Certain medicines used to treat hypertension (diuretics, ace inhibitors) can also cause you to lose potassium. Certain kidney diseases can result in severe potassium loss. Severe hypokalemia can trigger irregular heart rhythms that can lead to death. [3]

High potassium (hyperkalemia) can result from kidney diseases and certain medicines that decrease the amount of potassium excreted by your kidneys (such as potassium-sparing diuretics). People with type 1 diabetes, congestive heart failure, liver disease and an under-functioning adrenal glands are also at risk of developing hyperkalemia. [6] Sudden, very high levels of potassium can be life threatening and lead to cardiac arrest. [7]

Foods

Fruits and vegetables (especially potatoes) are an excellent source of potassium. Whole wheat flour and brown rice have more potassium that the refined products. Beverages like milk, coffee and tea are also high in potassium.[7] Hydration beverages also contain potassium, which, like sodium, works to reverse dehydration. Coconut water contains potassium, sodium and manganese and is often used for rehydration after physical activity or illness.

Supplements

Many, but not all supplements, have added potassium and, depending, on the form of potassium, may be absorbed through the gastrointestinal tract at different rates. Hydration beverages will contain potassium that, along with sodium, has been shown to improve hydration.

Health effects

People at risk for developing potassium deficiency are individuals with diseases of the bowel (inflammatory bowel disease) and people who are taking certain medications that cause the kidneys to excrete more potassium.

Risks

Inadequate potassium combined with high sodium can increase the risk of hypertension.

Benefits

Higher intake of potassium ( such as taking a supplement) may decrease blood pressure and reduce the risk of stroke and other cardiovascular diseases. Other potential health benefits include a decreased risk of kidney stones, improved bone health and better blood sugar control in people with diabetes.

Side effects

Potassium supplements can cause minor gastrointestinal (gut/intestinal) symptoms.

For more helpful information, see Dietary Guidelines for Americans

Magnesium

Magnesium works with 300 known enzyme systems in your body that regulate numerous bodily processes such as synthesizing proteins, controlling blood glucose (sugar), regulating blood pressure, muscle and nerve function, to name a few. Magnesium is also involved in DNA and RNA synthesis -which are the building blocks of your genes -and helps with the transport of calcium and potassium across the membranes of your cells to keep your nerves, muscles and heart rhythm working properly. [8]

Fifty to 60% of magnesium is stored in your bones, while the rest is stored in other soft tissues. Only 1% of magnesium is in your serum, and this level is very tightly controlled.

Your kidneys are the main regulators of magnesium in your body.

Imbalance

Low magnesium (hypomagnesemia) is uncommon in healthy people. Certain health conditions however can increase the loss of magnesium. For example, alcohol dependence can lead to hypomagnesemia through malnourishment, magnesium loss through the kidneys and gastrointestinal tract through vomiting, diarrhea and fatty stools. Certain medicines-such as diuretics and proton pump inhibitors (PPI), (used to treat heart burn)-, when taken for prolonged periods of time, can also cause magnesium deficiency.

High magnesium (hypermagnesemia) is not very common. Some causes are an overuse of drugs that contain magnesium such as laxatives or antacids, treatment with lithium, and medical conditions such as hypothyroidism ( a poorly functioning thyroid gland).

Foods

Foods that contain dietary fiber as well as spinach, legumes, nuts, seeds, and whole grains are good sources of magnesium. Tap, mineral, and bottled waters can also contain magnesium.

Supplements

There are a number of magnesium formulations available: magnesium chloride, magnesium oxide, magnesium citrate, magnesium carbonate, magnesium sulfate, magnesium lactate, magnesium oxide, magnesium orotate.

Health effects

People at risk of magnesium deficiency are individuals who don’t consume enough magnesium or have health conditions that decrease the amount of magnesium absorbed from the gut or that increase magnesium loss from the body. Individuals with gastrointestinal diseases, chronic alcoholism, type 2 diabetes and the elderly, who are more likely to have chronic health conditions ,have a bigger risk of having low magnesium levels. Low magnesium levels have also been associated with cardiovascular disease, Alzheimer’s disease, diabetes, hypertension, migraine headaches and attention deficit disorder (ADHD). [20]

Risks

High doses of magnesium from taking supplements can cause diarrhea, nausea and vomiting. Extremely high doses of magnesium can actually be fatal, especially in individuals whose kidneys may not be functioning properly.

Magnesium can also interfere with the effectiveness of certain medicines by decreasing the amount of drug absorbed into your system. Examples are some antibiotics and bisphosphonates ( medicines used to treat bone loss).

Benefits

Magnesium supplementation may lower blood pressure, reduce the risk of type 2 diabetes, decrease the risk of osteoporosis and prevent migraine headaches.

For more helpful information, see Dietary Guidelines for Americans

Calcium

Calcium is the most important mineral in the body and is necessary of the relaxation and contraction of blood vessels, muscle and nerve function, and the regulation of hormone secretion. 99% of calcium is stored in your bones and teeth, with only 1% free to circulate in your blood to carry out important functions. Calcium levels in your blood are tightly regulated and are controlled by the release of calcium from your bones. Some calcium is also removed from the body through urine, feces and sweat. [9]

Your bones are constantly being remodeled, resorbing and depositing new calcium into new bone. But as you age, there is more breakdown of bone than formation of new bone, which increases the risk of osteoporosis (brittle and fragile bones).

Imbalance

Low calcium (hypocalcemia) usually is due to medical problems such as kidney failure. Certain medicines can also cause hypocalcemia. Hypocalcemia can also be the result of major treatments such as surgical removal of the stomach.

Only about 30% of the calcium that you ingest is absorbed, and many factors can affect calcium absorption in the intestines. For one, calcium absorption will naturally decrease with age. There are also some foods like spinach, sweet potatoes and collard greens that can actually bind to calcium, so that less is absorbed. Alcohol and caffeine can both increase calcium excretion and reduce calcium absorption, and magnesium containing antacids can increase calcium excretion.

High calcium (hypercalcemia) in the blood can occur with high intake of calcium supplements. Though very high calcium levels are usually due to medical conditions such as an overactive parathyroid gland ( hyperparathyroidism) or cancer. Medicines like certain diuretics can also increase the risk of hypercalcemia.

Factors that improve calcium absorption are Vitamin D (from food, from skin exposed to sunlight, or taking vitamin D supplements)

Foods

Milk, yogurt and cheese provide a rich source of calcium as do vegetables such as kale, broccoli Chinese cabbage.

Supplements

There are several forms of calcium supplements, but calcium carbonate and calcium citrate are the two main preparations. Calcium carbonate is well absorbed when taken with food, while calcium citrate can be taken with or without food. You can also find calcium carbonate in antacid products like Tums®.

Health effects

People who are at risk of developing a deficiency in calcium are postmenopausal women, athletic women who are amenorrheic (who do not have menstrual cycles for prolonged periods of time), as well as individuals with dietary issues like lactose intolerance or who follow diet restrictions such as vegetarians.

Risks

Very high calcium intake from supplements can cause kidney malfunction and kidney stones. Some studies have also linked high calcium intake from supplements with a possible increase in the risk of heart disease and prostate cancer (though other studies have found a decreased risk).

Calcium can interfere with the absorption of several drugs such an antibiotics, thyroid medication, seizures medications among others.

Benefits

Bone loss is one of the serious consequences of calcium deficiency. Regular exercise (both weight bearing and resistance) combined with adequate calcium intake has been shown to support bone health. Calcium supplementation has also been shown to reduce the risk of fractures and falls in elderly people who live in institutions such as nursing homes [10]. The Food and Drug Administration (FDA), supports the health claim that ‘Adequate calcium and vitamin D as part of a healthful diet, along with physical activity, may reduce the risk of osteoporosis in later life ‘. [11]

Calcium supplementation may also reduce the risk of developing hypertension, especially pregnancy-induced hypertension (preeclampsia).

Side effects

A high calcium intake can cause constipation and interfere with iron and zinc absorption. Calcium carbonate may cause more side effects such as gas, bloating or constipation.

For more helpful information, see Dietary Guidelines for Americans

Chloride

Chloride is the main negative ion found in all extracellular fluid (fluid outside of your cells). Chloride works with sodium and potassium to balance acids and bases (pH) in your body. Chloride also helps with proper nerve transmission, digestion of proteins in your stomach, and regulates the movement of fluid inside and outside of cells. Excess chloride is normally removed in the urine, sweat and bowels[13] [14]

Imbalance

A low chloride level (hypochloremia) results from loss of chloride and tends to follow the same pattern as sodium loss. So, conditions like chronic diarrhea, vomiting, heavy and persistent sweating and kidney disease can lead to hypochloremia. Low chloride can also be seen in people with medical conditions like congestive heart failure ( weak heart muscle that can longer pump blood efficiently), poor functioning adrenal gland, chronic lung diseases and individuals who suffer from burns. Certain medicines such as laxatives, diuretics, steroids and bicarbonates can also decrease your blood chloride levels.

Severe dehydration, certain medicines like those used to treat glaucoma , and poorly functioning kidneys can be responsible for high chloride levels (hyperchloremia). [15]

Food

Much like sodium, you get most of your chloride from table salt (Na+Cl-), with much smaller amounts coming from potassium chloride. Processed foods are also high in chloride.

Supplements

Magnesium chloride and potassium chloride are two formulations that contain chloride.

Health

Severe dehydration from poor water intake is the main cause of chloride deficiency from a dietary perspective.

Risks

Consuming high levels of chloride may increase your risk of developing hypertension. [16]

Benefits

See benefits associated with magnesium supplementation.

Bicarbonate

Bicarbonate is an important electrolyte that buffers acid as it builds up in your body. The kidneys regulate bicarbonate production. Once produced, bicarbonate makes its way to the lungs where you exhale it a carbon dioxide (CO2). Bicarbonate controls the acid base balance in your body. For example, when you exercise and your muscles produce too much lactic acid, bicarbonate with help to neutralize the acid build up. Bicarbonate also interacts with sodium, potassium and chloride. [17]

Imbalance

Low levels of bicarbonate can lead to too much acid in your body (metabolic acidosis). Many conditions can lead to low levels of bicarbonate in your blood such as diarrhea, kidney disease and liver failure. A variety of medicines can also lower your bicarbonate level.

High levels of bicarbonate can occur with conditions that cause your blood pH to rise ( become alkaline). For example, vomiting and dehydration can cause you to lose acid. Eating disorders like anorexia and lung diseases can also lead to the same process. Several medicines can also increase your bicarbonate levels.

Formulations

Some formulations of bicarbonate include sodium bicarbonate, potassium bicarbonate and magnesium bicarbonate water solutions. Sodium bicarbonate has many uses. Potassium bicarbonate is used to treat low potassium levels.

Health

Benefits

Sodium bicarbonate can reduce stomach acid and help calm indigestion, help with kidney disease for people whose kidneys cannot excrete enough acid from their blood stream, soothe insect bites, decrease tooth decay, and can also improve the effectiveness of certain chemotherapy drugs used to treat cancer, mainly the drugs that work better in a more alkaline environment. People also take sodium bicarbonate to improve their exercise performance[18]

Sodium bicarbonate is also used intravenously (a solution given through the veins) in emergency situation to resuscitate your heart, to treat overdoses of cocaine, poisoning from certain allergy medicines and fluid in your lungs that has been caused by certain chemicals.

Risks

Taking large amounts of bicarbonate to boost your performance before a run can make you sick. Bicarbonate given intravenously must be done under strict medical supervision since there a certain medical conditions in which sodium bicarbonate should not be used.

Side effects

Very high doses of bicarbonate taken over a prolonged period of time can cause serious complications such as an imbalance in other electrolytes and even stomach rupture. [19]

References
  1. Tai, C.Y., et al., An amino acid-electrolyte beverage may increase cellular rehydration relative to carbohydrate-electrolyte and flavored water beverages. Nutr J, 2014. 13: p. 47.
  2. https://dictionary.webmd.com/electrolytes
  3. https://www.ncbi.nlm.nih.gov/books/NBK234935/
  4. Naganathan, S. and M.A. Al-Dhahir, Hypernatremia, in StatPearls. 2018: Treasure Island (FL).
  5. https://www.accessdata.fda.gov/scripts/InteractiveNutritionFactsLabel/sodium.html.
  6. Viera, A.J. and N. Wouk, Potassium Disorders: Hypokalemia and Hyperkalemia. Am Fam Physician, 2015. 92(6): p. 487-95.
  7. https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
  8. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/
  9. Cranney A, H.T., O’Donnell S, Weiler HA, Puil L, Ooi DS, Atkinson SA, Ward LM, Moher D, Hanley DA, Fang M, Yazdi F, Garritty C, Sampson M, Barrowman N, Tsertsvadze A, Mamaladze V. , Effectiveness and Safety of Vitamin D in Relation to Bone Health. (Prepared by the University of Ottawa Evidence-based Practice Center (UO-EPC) under Contract No. 290-02-0021.AHRQ Publication No. 07-E013. Rockville, MD: Agency for Healthcare Research and Quality., 2007.
  10. https://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation/LabelingNutrition/ucm152626.htm
  11. Curhan, G.C., et al., A prospective study of dietary calcium and other nutrients and the risk of symptomatic kidney stones. N Engl J Med, 1993. 328(12): p. 833-8.
  12. https://www.webmd.com/a-to-z-guides/what-is-a-chloride-test#1
  13. https://www.ncbi.nlm.nih.gov/books/NBK234935/#_ddd0000264_
  14. https://www.healthline.com/health/chloride-test-blood#procedure
  15. McCallum, L., S. Lip, and S. Padmanabhan, The hidden hand of chloride in hypertension. Pflugers Arch, 2015. 467(3): p. 595-603.
  16. https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=bicarbonate
  17. https://www.webmd.com/a-to-z-guides/baking-soda-do-dont#1
  18. https://www.webmd.com/vitamins/ai/ingredientmono-1470/sodium-bicarbonate
  19. Grober, U., Schmidt, J., & Kisters, K. (2015). Magnesium in Prevention and Therapy. Nutrients, 7(9), 8199-8226. doi:10.3390/nu7095388