HeraSphere #47: To Electrolyte or Not?

Hi friends,

My 15 year old son has been asking me to buy him electrolytes for soccer practice. Nuun one day, LMNT the next. I said yes mostly because there didn’t seem to be any harm. But I personally always thought that electrolytes were a marketing ploy for people who already eat enough salt.

With the heat dome July 4th weekend parking itself over the DC over as its epicenter, I thought it would be an appropriate time to finally get to the bottom of the electrolyte hype. So I did the research I'd been putting off.

The TL;DR

• Electrolytes are minerals your body runs on constantly. Sodium, potassium, calcium, and magnesium regulate fluid balance, blood pressure, and how your muscles and nerves fire.

• However, most of us don't need to supplement them. Your kidneys already manage sodium balance on their own, and you'll make up what you lose through regular meals.

• The format you buy matters more than the brand. Powder delivers 500-1,000mg of sodium per serving because it's almost entirely minerals. Tablets cap around 300mg because a chunk of the tablet has to be citric acid and bicarbonate just to fizz.

• Heat, duration, and sweat rate over hours decide who actually needs this, not a fixed 60-minute clock. Two hours of soccer in a heat dome is a real demand.

• The supplement aisle has no regulation, so caveat emptor. One hydration researcher found arsenic in electrolyte powders given to college athletes.

What Electrolytes Actually Do

• Electrolytes are minerals that carry an electrical charge, and sodium, potassium, magnesium, and calcium do most of the work. Sodium controls fluid balance and blood pressure. Potassium works opposite sodium to regulate fluid inside your cells and keep your heart rhythm steady. Magnesium supports muscle contraction and nerve signaling. Calcium triggers muscle contraction, including your heartbeat.

• You're already eating most of what you need. Potassium is in a banana, sodium is on a pretzel, magnesium is in spinach and almonds, calcium is in yogurt. They're in the food most people eat every day.

• Sweat carries out a mix of these minerals, not just sodium, and losing too much of any of them causes problems. Low potassium contributes to muscle cramps and irregular heartbeat. Low magnesium shows up as cramping and fatigue too, which is part of why cramping gets blamed on "electrolytes" broadly instead of one specific mineral.

• Sodium is the one that actually needs replacing during real exertion, which is why it dominates every serious electrolyte formula. Sports nutrition guidance generally lands on 200-800mg of sodium per serving with potassium at roughly a third to a half of that, and magnesium in smaller amounts still, since potassium and magnesium losses are usually covered by a normal diet even when sodium losses aren't.

• Most electrolyte products are formulated almost entirely around sodium, with small or token amounts of the other three. That's worth knowing before you assume a packet is replacing everything sweat takes out.

When Water is Not Enough

• Your kidneys already run a return-and-refund system for sodium, which is why most exercise doesn't require supplementation. A hormone rises when sodium runs low to pull it back into your bloodstream, and drops when you've eaten more than you need so your kidneys flush the excess. This is constant, automatic, and unaffected by whether you drink a sports drink.

• It's been established for over a decade that electrolytes don't move the needle on performance. The marketing from sports drink companies is louder than the science.

• An ultramarathon study found sodium supplements had no measurable effect on race performance, and dehydrated runners actually finished faster than overhydrated ones. The evidence against routine supplementation is strong,

• The threshold where this flips is roughly 60 to 90 minutes of real exertion, and heat shortens that window further. The American College of Sports Medicine’s heat stress guidance marks this as the point where sweat losses can outpace what water and a normal diet replace. Three hours of soccer practice is well past it, especially in a heat wave

• Hyponatremia, sodium too low from drinking more fluid than your body can balance, is the risk. It shows up in endurance events lasting hours when people over-hydrate on plain water without replacing sodium, and severe cases cause seizures or death.

• This is about exercise and heat, not illness. If you're dealing with vomiting or diarrhea, the fluid and sodium loss is faster and different, and the standard "drink water, take electrolytes" advice is correct there. That's a separate situation from soccer practice.

Powder, Tablet, or Capsule: The Format Actually Matters

• A tablet spends its size budget on chemistry before it gets to spend any on sodium. Effervescent tablets use citric acid and sodium bicarbonate to create the fizz. That reaction produces sodium citrate, which your body absorbs like any other sodium source, but the acid and bicarbonate still take up most of the tablet's fixed size. Nuun Sport tops out at 300mg of sodium per tablet as a result.

• Powder skips the reaction and spends the whole serving on minerals. A typical scoop delivers 500-1,000mg of sodium.

• Capsules are the lowest-dose format. 100-200mg of sodium each means four to six capsules to match one scoop of powder, and swallowing pills skips the fluid-pacing benefit of drinking electrolytes dissolved in water.

• Hypernatremia, sodium too high, is a medical condition but not a realistic risk from a sports drink or supplement. There isn't enough sodium in a standard serving to push a healthy person's blood sodium too high.

What Hormonal Shifts Actually Mean for Midlife Women

• Your kidneys' sodium regulation runs through estrogen and progesterone too, not just your sweat glands. Research found progesterone competes with aldosterone, the hormone that tells your kidneys to hold onto sodium, while estrogen affects water retention on its own. Perimenopause moves both hormones in and out of range unpredictably.

• Dizziness or fatigue during exercise in heat isn't automatically "just a hot flash." Exercise scientist Dr. Stacy Sims collapsed from hyponatremia at the Ironman World Championship in Kona during the luteal phase of her cycle, when progesterone was highest and most actively displacing sodium retention. Three other women in the medical tent that day had the same pattern.

• Even though most of us are not doing Ironman’s, if you're perimenopausal and active in heat, treat dizziness or unusual fatigue as a possible sodium signal.

Nobody's Checking the Contents of the Packet

• None of what's actually in electrolyte products is verified. The FDA classifies electrolyte powders as dietary supplements, which means the agency doesn't check contents or claims before a product hits shelves.

• A hydration researcher found arsenic in the products she was studying. In 2015, a study tested Muscle Milk and Gatorade powders given to college athletes and found unsafe arsenic levels. The athletes showed no signs of harm, but it's a real example of what an unregulated category means in practice.

• Sodium content ranges from 10mg to 1,000mg per serving with zero standardization. "Clean" doesn't mean what the label implies either: flavored LMNT sticks contain maltodextrin as a flavor carrier, disclosed only in the fine print.

• Read the sugar content, not just the sodium claim. Some drinks can carry nearly as much sugar as soda!

I'm still buying my son electrolytes, but now I check the label for sodium and sugar content. I was mostly right about the marketing hype. Its important for my son when he has 3 hour long practices in heat to avoid cramping and mitigate sodium loss- but a banana and pretzels before practice may do the same thing.

For me personally, unless I'm sweating through extreme heat for a long stretch, I'm sticking with water. Not an exciting conclusion, but it saves me some money :)

Stay cool out there,
Lilly

P.S. If you've got a kid begging for a specific electrolyte brand and you're not sure if it's hype, send this to the parent standing next to you at practice. She's likely asking herself the same question.

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Note: While I love diving deep into research and sharing what I've learned about women's health and wellness, I want to be crystal clear: I'm a passionate health advocate and researcher, not a medical professional. Think of me as your well-informed friend who does extensive homework – but not your doctor.

Everything I share in HeraSphere comes from careful research and personal experience, but it's meant to inform and inspire, not to diagnose or treat any medical conditions. Your body is uniquely yours, and what works for one person might not work for another. Always consult your healthcare provider before making significant changes to your diet, exercise routine, or wellness practices, especially if you have underlying health conditions or take medications.

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