All About Electrolytes – Sodium, Magnesium, and Potassium
Written by: Ryah Nabielski, MS, RDN
When it comes to hydration, water is the first thought. But electrolytes are the other piece of the puzzle. Electrolytes are essential for life! If you’re like most Americans, you aren’t getting enough of some and too much of others.
Now that it’s spring and we’re moving into warmer weather, your electrolyte needs may increase to support living in a hot or dry climate or with more outdoor activity.
Today’s article will dive into electrolytes and their importance for overall health. Plus, learn how to balance electrolytes to improve hydration and health with food and supplements. We’ll cover:
- What are electrolytes?
- Sodium functions, needs, and food sources
- Magnesium functions, needs, and food sources
- Potassium functions, needs, and food sources
- When to use electrolyte supplements
Let’s jump in!
What Are Electrolytes?
Electrolytes are dietary minerals that naturally occur in food and drinking water. They maintain fluid homeostasis (balance) in the body.
The body is abundant in fluid, which is found inside the cells and outside the cells in blood, lymphatic fluid, and cerebrospinal fluid. Electrolytes are dissolved in the fluids, creating an electrical gradient and allowing cell and body functions.
Electrolyte minerals are essential for life and include:
- Chloride
- Calcium
- Phosphorus
- Bicarbonate
We will focus on sodium, magnesium, and potassium, which play critical roles in health and are typically found in electrolyte supplements.
Sodium Functions
Sodium is the primary electrolyte in fluids outside of cells, and maintaining sodium levels in a tight range is essential for life. Sodium levels help control blood volume and pressure. The brain monitors sodium levels and controls the intake of water and sodium and the excretion of water and sodium by the kidneys to maintain optimal levels.
Low sodium (hyponatremia) is more common in older adults and those with chronic disease. While we commonly think of high sodium (salt) intake associated with high blood pressure, only some people are salt-sensitive, meaning that salty foods will increase blood pressure. Salt sensitivity may be related to genetic factors, underlying medical conditions, and deficiency in other electrolytes.
Sodium Needs and Food Sources
The adequate intake (AI) for sodium is 1.5 grams per day for adults, which is the amount of sodium in 3.8 grams of salt (sodium chloride), or about two-thirds of a teaspoon.
Most whole foods don’t contain much natural sodium. Salt is typically added as a preservative. Helpful dietary sources of sodium are:
- Sea salt
- Fish and seafood
- Seaweed
- Fermented vegetables
About 70% of sodium in the U.S. diet comes from processed, packaged foods like bread, baked goods, deli meat, pizza, canned foods, frozen meals, and salty snack foods like chips and pretzels.
The medical community emphasizes reducing salt in the diet for heart health. However, the emphasis should really be moving away from packaged food and towards whole-food cooking, which will provide a better balance of electrolytes.
Bottom line: Sodium gets a bad rap, but it’s essential for life. Healthy people can add sea salt to home-cooked meals.
Magnesium Functions
Magnesium is a macromineral; we need relatively large amounts to support total body health. Magnesium is a cofactor in more than 300 enzymatic reactions in the body. Along with being an electrolyte, magnesium is essential for:
- Energy metabolism
- Bone structure
- DNA synthesis
- Glutathione production (the body’s “master antioxidant”)
- Building proteins
- Muscle function
- Nervous system function
- Blood sugar balance
- Blood pressure maintenance
Most magnesium is inside cells (like potassium) or stored in the bone, so it’s hard to measure. The kidneys control magnesium balance: when magnesium levels are too high in fluids, the kidneys will release more magnesium into the urine.
Magnesium Needs and Food Sources
The recommended dietary allowance (RDA) for magnesium is 400 mg daily for men ages 19 to 30 and 420 mg per day for men 31 and over. For women, the recommendation is 310 mg per day and 320 mg per day for those 31 and older. Women also have higher needs during pregnancy and lactation.
U.S. data suggest 48% of Americans don’t get enough magnesium in their diet. Because of depleted soils and other factors, magnesium levels in the food supply may be lower than they once were. Even when consuming a nutrient-dense whole-food diet, it can be hard to get enough.
It seems we are all at risk for magnesium deficiency, but those more at risk include people with certain diseases, heavy drinkers, older adults, and those taking specific medications. Low magnesium levels contribute to high blood pressure, osteoporosis, diabetes, and more.
Good food sources of magnesium include:
- Seeds – pumpkin, chia
- Nuts – almonds, cashews
- Peanuts
- Beans
- Spinach and other leafy green veggies
- Fish
- Whole grains – oats, brown rice
- Banana
- Avocado
- Milk
Bottom line: Most people need more magnesium from quality sources. Magnesium is also a very safe supplement.
Potassium Functions
While sodium is the most abundant electrolyte outside cells, potassium is the most concentrated inside cells. (It’s 30 times higher inside cells than outside cells.) Potassium is critical for normal cellular function by maintaining an electrochemical gradient with sodium that allows for nerve conduction, muscle contraction, kidney function, and more.
Like the other electrolytes, the body tightly regulates potassium levels, which works excellently in healthy people. Potassium is absorbed well, and the kidneys excrete excess into the urine.
Low potassium levels result from insufficient potassium in the diet or certain medications, which can contribute to high blood pressure, kidney stones, and bone loss. Interestingly, low magnesium levels can increase potassium excretion in the urine, contributing to lower potassium levels.
Potassium Needs and Food Sources
The adequate intake for adult men is 3400 mg of potassium per day and 2600 mg daily for women. Most people in the United States don’t meet these requirements. The average actual intake is around 3000 mg for men and 2300 mg for women.
Potassium is widespread in whole plant and animal foods. Good food sources include:
- Dried fruit – apricots, prunes, raisins
- Lentils
- Winter squash
- Potato
- Legumes
- Banana
- Dairy – milk, yogurt
- Spinach
- Meat – chicken, beef
- Fish
- Tomato
- Asparagus
- Cantaloupe
Bottom line: You probably need more potassium in your diet!
Electrolyte Supplements and Best Practices
Meeting your daily electrolyte needs with food is a good start, but often, you may need even more electrolytes to support optimal health and prevent dehydration.
Any time you sweat or lose fluids from illness (like the flu), you lose fluids and electrolytes. In mild cases, replacing water may be enough, but here are some circumstances where you want also to replace or increase electrolytes:
- High-intensity exercise
- Endurance exercise
- Hot Yoga
- Passive sweating in a sauna or hot tub
- Living in a hot or dry climate
- Fluid loss from vomiting or diarrhea
- Pregnancy and lactation (water and electrolyte needs are higher)
Twenty2 Nutrition Electrolytes is designed to be used before or during workouts to sustain energy and support rehydration. It does contain some caffeine (60 mg per serving).
For a caffeine-free option, choose Twenty2 Nutrition Stimulant-Free Electrolytes. (Discover if you are caffeine-sensitive here.)
Both Twenty2 Nutrition electrolyte supplements contain:
Electrolytes are minerals that support optimal fluid balance in the body, which is essential for all body functions and life itself. To support healthy electrolytes, choose more whole, mineral-rich foods like fruits, vegetables, beans, and meat while decreasing high-sodium processed foods. Shifting the diet this way can make a significant difference in hydration and exercise performance. When you need more support, choose a quality electrolyte supplement like Twenty2 Nutrition Electrolytes or Twenty2 Nutrition Stimulant-Free Electrolytes. And don’t forget to drink water!
This article is for educational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified healthcare provider before changing your diet or beginning a new supplement, especially if you are pregnant or breastfeeding, take medication, or have a medical condition.
Ryah Nabielski, MS, RDN is a Registered Dietitian, functional nutritionist, writer, and recipe creator. Ryah helps clients use a natural, food-as-medicine approach to improve fertility, pregnancy, hormone balance, autoimmunity, and discover a healthy relationship with food and body. Learn more about Ryah and her private practice at econutrition.co.
References
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9363595/
- https://lpi.oregonstate.edu/mic/minerals/sodium
- https://pubmed.ncbi.nlm.nih.gov/32862203/
- https://www.fda.gov/food/nutrition-education-resources-materials/sodium-your-diet
- https://ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/
- https://ods.od.nih.gov/factsheets/Potassium-HealthProfessional/
- https://pubmed.ncbi.nlm.nih.gov/34578811/
