When we talk about “getting enough electrolytes,” we usually mean the big three: sodium, potassium, and magnesium. There are many others, including calcium, chloride, and bicarbonate, but the big three are the ones targeted by supplement and sports nutrition companies.
In part, that’s because sodium especially, but also potassium and magnesium, are lost through sweat. Athletes need to replenish these electrolytes during and after hard workouts or endurance outings in order to maintain optimal hydration and performance. Sodium and potassium work together to manage fluid balance throughout the body and facilitate muscle contractions and nerve firing. Magnesium is critical for cellular energy production and the transport of sodium and potassium across cell membranes.
I’m not going to go into a lot of detail about the other functions of electrolytes in the body since Mark recently covered the topic in his Electrolytes 101 post. Suffice it to say that if you don’t maintain the proper levels of electrolytes, you’re in a world of hurt.
Should I Be Taking Electrolyte Supplements?
Not everyone needs to supplement with electrolytes, but everyone needs to get the right amount. Your kidneys do a good job keeping electrolytes in balance by retaining or excreting specific electrolytes as needed. However, the kidneys can only do their job if you provide enough electrolytes to begin with, and there’s the rub. Even Primal folks who consume abundant produce and animal products may struggle to get enough electrolytes from their food due to mineral-depleted soil. Paleo godfather Loren Cordain speculates that potassium intake in particular lags behind our biological needs.1
Furthermore, if you’ve jumped on the ketogenic train, you need more electrolytes than the average person. When you drop your carb intake, insulin secretion decreases accordingly. This triggers ketone production as well as a rapid flush of electrolytes. Failure to replenish lost electrolytes, particularly sodium, is probably the number one culprit behind the dreaded keto flu.
Sports drinks are not the best way to up your electrolyte intake, though. Most of them are designed to provide energy (read: sugar) and hydration first and foremost. They probably won’t offer the amount of electrolytes you want, plus they usually contain other undesirable ingredients you don’t need. Luckily, it’s easy to up your electrolyte intake with better, more Primal-friendly sources.
How Much Sodium, Potassium, and Magnesium Do You Need?
Sodium: The current recommended daily intake for adults is 1,500 mg per day, but that’s probably not enough for most people. The sweet spot seems to be between 4 and 6 grams per day for adults who do not have salt-sensitive hypertension or kidney disease.
Potassium:2 The FDA’s recommended daily intake (RDI) is 4,700 mg per day.
Magnesium:3 For adult females, 310 mg per day up to age 30, 320 mg per day thereafter. For adult males, 400 mg per day up to age 30, 420 mg per day after that.
Keto Dieters’ Electrolyte Requirements
Keto dieters should aim for:
3 to 5 grams (3,000 to 5,000 mg) of sodium
1 to 3.5 grams (1,000 to 3,500 mg) of potassium
300 to 500 mg of magnesium
These are in addition to what you get from food. If you are already getting at least the RDI of potassium from your diet, you might choose not to add more. However, as I said, it’s unlikely that you consistently get enough.
How to Get Electrolytes without Sports Drinks
Start with Food
Getting electrolytes from your diet is preferable to supplementing. Start by estimating your typical daily electrolyte intake, ideally by tracking your food for a few days using an app. I prefer Cronometer, but any app that provides detailed nutritional information will do. Don’t forget to track beverages, too.
If you find that you’re not hitting your targets, try adding more electrolyte-rich foods first, then supplement as needed.
How to Get Sodium in Your Diet
(Note: All the nutrition information below comes from Cronometer.)
Bacon and other cured meats, canned fish, or salted nuts can contribute up to a few hundred mg of sodium per serving. Smaller amounts naturally occur in some produce like beets and carrots, and in seaweed and fresh seafood. Dairy products also contain sodium, and even your drinking water contributes a little.
By and large, though, most of the sodium you consume in a day comes from the salt you add to your food. Different types of salt contain different amounts of sodium. A teaspoon of sea salt has about 2,100 to 2,300 mg of sodium, whereas a teaspoon of kosher salt only has between 1,100 and 1,900 mg.
Primal eaters should feel free to salt their food liberally. Your food will taste better if you do! Also, adding a generous pinch of salt to your drinking water enhances the body’s ability to absorb the water so you stay hydrated. (Add a squeeze of lemon to mask the taste.)
Foods Rich in Potassium
Primal eaters usually don’t include many of the highest-potassium foods in their diets: legumes, dried fruits, bananas. No worries! A medium-sized banana contains 422 grams in a medium-sized fruit. There are plenty of Primal-friendly options that beat it. Here’s just a sampling:
Avocado (1 whole, 136 g): 690 mg
Clams, cooked (10 small, 100 g): 628 mg
Butternut squash (1 cup cubed, 205 g): 582 mg
Spinach, raw (3 cups, 90 g): 502 mg
Beets, cooked (1 cup diced, 157 g): 479 mg
These don’t beat bananas, but they still get honorable mentions:
Potatoes are still controversial in the ancestral health space, but they contain more potassium than any of the foods listed above. A medium-sized baked potato (131 g) clocks in at 512 mg of potassium. Eating the skin nets you an additional 400 mg! If you don’t want to eat white potatoes, and you’re not aiming for very low carb intake, a medium-sized sweet potato (150 g) delivers 713 mg of potassium.
As you can see, though, it takes quite a lot to hit the RDI of 4,700 mg per day, even if you eat plenty of these relatively high-potassium foods.
Best Foods for Magnesium
With both magnesium and potassium, you’ll get some from most Primal foods. Some of the higher-magnesium foods are:
Almonds, dry roasted (¼ cup, 35 g): 96 mg
Spinach, raw (3 cups, 90 g): 71 mg
Pumpkin seeds, roasted (¼ cup, 16 g): 42 mg
Chia seeds (1 Tbsp, 10g): 39 mg
Avocado (1 whole, 136 g): 39 mg
Sockeye salmon, raw (3 ounces, 85 g): 23 mg
Remember, you don’t need nearly as much magnesium as you do potassium or sodium.
Supplement Electrolytes as Needed
You can purchase magnesium and potassium as individual supplements. Check your daily multivitamin/multimineral formula, too, to see how much you’re getting there.
The easiest way to add sodium is from good ol’ salt. Losalt is a lower-sodium salt that contains 1800 mg of potassium and 688 mg of sodium per teaspoon.
You can also buy electrolyte powders that you add to water. Read the labels to see how much sodium, potassium, and magnesium you are getting with each product and to make sure they don’t have added sugar. Some products don’t contain all three electrolytes, which might be desirable or not depending on what you need. Others contain all three but in paltry amounts. My personal favorite is LMNT, which contains good amounts of the big three in the correct proportions.
What about Baking Soda?
Some evidence suggests that baking soda is anti-inflammatory and can buffer acidosis, which is why it’s becoming increasingly popular among athletes and folks with autoimmune issues. It also seems to boost ketone production.4
The chemical formula for baking is sodium bicarbonate (NaHCO3). One-quarter teaspoon contains 315 mg of sodium, plus bicarbonate, another electrolyte. The downside to using baking soda as a supplement is that it can cause significant GI distress if you overdo it. Start small!
A Note on Safe Supplementing
It’s almost impossible to overdo electrolyte intake when you’re talking about the minerals that naturally occur in real food. However, supplementing is a different story. With any electrolyte, you can run into problems by taking too much. That’s why I suggest tracking your food intake first—so you know how much more of each you actually need.
In particular, excessive potassium can lead to heart arrhythmias. When taken correctly, potassium supplements are generally considered to be safe for adults whose kidneys are healthy. As always, ask your doctor if you’re not sure if they’re right for you.
Lindsay Taylor, Ph.D., is a senior writer and community manager for Primal Nutrition, a certified Primal Health Coach, and the co-author of three keto cookbooks.
As a writer for Mark’s Daily Apple and the leader of the thriving Keto Reset and Primal Endurance communities, Lindsay’s job is to help people learn the whats, whys, and hows of leading a health-focused life. Before joining the Primal team, she earned her master’s and Ph.D. in Social and Personality Psychology from the University of California, Berkeley, where she also worked as a researcher and instructor.
Lindsay lives in Northern California with her husband and two sports-obsessed sons. In her free time, she enjoys ultra running, triathlon, camping, and game nights. Follow along on Instagram @theusefuldish as Lindsay attempts to juggle work, family, and endurance training, all while maintaining a healthy balance and, most of all, having fun in life.