You have probably seen both claims in the same week. One brand says sugar is the enemy and their zero-sugar stick is the only clean option. Another says that without glucose your body cannot absorb sodium at all, so you are basically drinking salty water. Both are confident. Both are selling something.
The real story about sugar in electrolyte drinks is less dramatic and a lot more useful. Sugar is a dial, not a switch. How far you turn it depends on what you are actually doing that day.
What sugar actually does in an electrolyte drink
Your small intestine has a transport protein called SGLT1, the sodium-glucose linked transporter. It does what the name says: it carries sodium and glucose across the intestinal wall together, as a pair. Water follows passively, pulled along by the osmotic gradient that transport creates.
This is not supplement-industry theory. It is the mechanism behind oral rehydration solution, the formula used worldwide to treat dehydration from diarrheal illness. ORS deliberately pairs sodium with a modest amount of glucose in roughly balanced amounts, because that pairing moves water across the gut wall faster than salt or sugar can alone. It is one of the more consequential public health tools of the last century, and the glucose in it is not decoration.
So the pro-sugar camp is pointing at something real. They are just quiet about the rest of it.
Why zero-sugar electrolytes still hydrate you
Here is what gets left out: SGLT1 is not the only door.
Sodium also crosses the intestinal wall through sodium-hydrogen exchangers and alongside amino acids, and neither of those routes needs glucose. Plain water is absorbed perfectly well on its own, too. Humans managed to stay hydrated for a very long time before anyone engineered a stick pack.
A zero-sugar electrolyte drink absorbs somewhat more slowly than a glucose-paired rehydration solution. It does not fail to absorb. That distinction gets flattened in marketing copy, and it matters.
The SGLT1 advantage counts most when the gap between how fast you are losing fluid and how fast you can replace it is wide. Heavy sweating in real heat. An illness that is actively emptying you out. On an ordinary Tuesday, that speed difference is a rounding error you will never feel.
When sugar in electrolyte drinks helps, and when it gets in the way
Long, hard efforts
Past roughly an hour of sustained hard work, you are not just losing fluid and sodium. You are burning through muscle glycogen. Carbohydrate does double duty here: it speeds sodium and water uptake, and it is fuel.
Worth separating those two jobs, though, because they are usually solved by different things. Endurance athletes need far more carbohydrate than any electrolyte stick provides — commonly 30 to 90 grams an hour, which is gels, chews, bananas, or a dedicated fuel mix. No hydration stick on the market is your carb strategy for a four-hour ride, including the sugary ones. What a stick can do well is cover the fluid and sodium side on a predictable hourly schedule while your fuel comes from food. Running those as two separate systems tends to work better than hoping one drink does both jobs adequately.
Recovering from a stomach bug
This is the exact scenario oral rehydration solution was built for, and it is the one case where the glucose pairing genuinely earns its keep at home. Use an actual ORS here rather than a hydration stick — the glucose-to-sodium ratio is the whole point of the formula, and it is not something a zero-sugar mix reproduces. Small, frequent sips beat large gulps. Very sugary drinks like soda or undiluted juice are the wrong tool too, for reasons covered in the next section. If dehydration is severe or prolonged, that is a conversation for a clinician, not a drink mix.
Everyday sipping, desk days, low-carb eating, fasting windows
If you are topping up after a warm afternoon, a normal workout, or a night of poor sleep, absorption speed is not your limiting factor. Whether you actually drink the thing is your limiting factor.
Sugar buys you very little physiologically in this scenario and costs you something real: calories you did not plan for, a glucose bump you did not need, and if you are eating low-carb or inside a fasting window, a reason to skip hydrating altogether. A drink you avoid hydrates you zero percent, no matter how elegant its transport mechanism.
Concentration matters more than grams
The number that governs how a drink behaves in your gut is not grams of sugar on the panel. It is concentration, meaning grams relative to the water you mix them into.
Fluids that are strongly hypertonic, more concentrated than your blood, briefly pull water out of your bloodstream and into the intestine before net absorption can happen. That is the mechanism behind the sloshing, heavy feeling from chugging soda or straight fruit juice mid-workout, and it is why sugary drinks can make diarrhea worse rather than better.
Traditional sports drinks land around six to eight percent carbohydrate, which is tuned for fueling during exercise rather than for fastest possible rehydration. Rehydration-focused formulas sit lower. This is the part almost no label explains: the same grams of sugar in half the water is a completely different drink.
Practical version: if a mix tells you to use twelve or sixteen ounces of water, use twelve or sixteen ounces of water. Mixing a stick into a small glass because you like it stronger changes the physiology, not just the flavor. If you need more electrolytes over a long session, the answer is another stick in another full bottle — not a stronger one.
How to read your own label
A few questions that cut through most of the noise:
- How many grams of sugar, and in how much water? Calculate the concentration yourself. Grams divided by milliliters of water, times one hundred, gives you a percentage. One wrinkle specific to supplements: FDA rules bar a Supplement Facts panel from printing a nutrient that rounds to zero, so a missing sugar line means the rounding handled it rather than the brand hiding it. We unpack that in how to read an electrolyte label.
- Is the sugar doing a job, or just tasting good? A gram or two for flavor is flavor. Fifteen grams is fuel. Both are legitimate. They are not the same product.
- What is the sweetener actually doing? Non-nutritive sweeteners — stevia, monk fruit, sucralose, or fermentation-derived Reb M — make a drink taste sweet without contributing to SGLT1 transport. That is fine if you did not need the transport boost. It is worth knowing either way.
- Does the sodium content match your use case? Sugar is only half the equation, and a heavily loaded sodium formula has its own tradeoffs.
This is roughly how we think about burbo. It is built for everyday hydration and workout support rather than for four-hour race days, which is why we went the no-sugar-load route: zero-calorie Reb M for sweetness, a trace of organic agave for flavor, and 327 mg of sodium per stick.
The way that plays out on a long, hot day is by the hour rather than by the bottle. 327 mg sits at the bottom of the American College of Sports Medicine's 300–600 mg-per-hour band, so roughly one stick per hour of sustained sweating keeps you inside the guidance, and a heavy salty sweater can take two in a hard first hour and still be within it. If the effort also runs long enough to need fuel, add the carbohydrate from food or gels alongside — that is a different job, and it is better solved by something built for it than by switching to a sweeter drink and hoping it covers both. Two sticks a day is comfortably fine and three is our practical ceiling, since each one also carries a full day's folate and B vitamins. Past that, keep the rhythm and get the extra sodium from food or a plain vitamin-free electrolyte.
The supplement facts panel is right there on the pack — worth checking against everything here, ours included.
The practical takeaway
There is no universally correct amount of sugar in a hydration drink, which is exactly why both marketing camps sound so certain. Match the drink to the day instead:
- Hard effort over an hour, or real heat: replace fluid and sodium hourly, and take carbohydrate alongside if the effort is long enough to need fuel.
- Illness with fluid loss: use an oral rehydration solution. The glucose and sodium pairing is doing real work there. Sip slowly.
- Everything else, which is most days: a low-sugar or sugar-free formula with sensible sodium is fine, and the flavor you will actually reach for matters more than the transport math.
Sugar in your electrolyte drink is not a moral question. It is a specification. Pick the one that matches the job.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. How this article was researched and written: our editorial standards.