Electrolyte marketing treats every athlete as identical. The measurements say otherwise: sweat sodium concentration varies roughly tenfold between individuals, which means generic hydration advice is wrong for most of the people following it.
Baker's review of sweat testing methodology puts typical sweat sodium somewhere in the range of about 10 to 90 mmol/L depending on the person, with sweat rate varying widely on top of that. A heavy, salty sweater training in July is losing an order of magnitude more sodium than a light sweater doing the same session. That's the case for electrolytes — not that everyone needs them, but that some people need far more than a sports drink provides and others need none at all.
The second scenario is dietary rather than athletic. Cutting carbohydrate drops circulating insulin, and insulin is a signal for the kidneys to retain sodium — so when it falls, sodium and water are excreted. That mechanism is a large part of both the rapid initial weight loss on keto and the headaches, fatigue and light-headedness people call "keto flu." It's a salt and water problem dressed up as a mysterious adaptation, and it responds to sodium.
One important caution in the other direction. More water is not automatically safer. Exercise-associated hyponatremia — dangerously diluted blood sodium — is caused primarily by drinking more fluid than you lose, and the international consensus statement is explicit that it can be fatal. Drink to thirst, replace sodium if you're a salty sweater or low-carb, and don't force fluid on a schedule.
How we picked
Most "electrolyte" products are sports drinks with a smaller sugar load and a larger price tag, so the first thing we did was read the sodium line. Sodium is the electrolyte lost in the largest quantity in sweat by a wide margin — typically several hundred to over a thousand milligrams per litre, with large variation between individuals — and it is the one most products under-dose. Anything supplying token sodium alongside a long list of trace minerals was ranked down regardless of how impressive the label looked.
From there: no added sugar unless the product is explicitly aimed at endurance fuelling, where carbohydrate is the point; magnesium in an absorbable chelated form rather than oxide; potassium present but sensibly dosed, since it is more readily obtained from food than sodium is; and a Health Canada NPN. We ranked on cost per serving at the sodium level a real user actually needs, which reshuffles the order considerably compared with cost per stick.
The Rankings
Keto Electrolyte Packets
1000mg of sodium per packet with zero sugar — far more than a conventional sports drink, which is the entire point. Built for low-carb dieters and heavy sweaters, the two groups whose losses the standard products under-serve. Overkill for a light sweater eating normal carbs.
Hydration Electrolyte Powder
The everyday option: lower sodium than LMNT, vegan, zero sugar, and under twenty dollars. Better suited to ordinary training in ordinary weather, where you want some replacement rather than aggressive repletion.
Electrolytes Variety Pack
Single-serve sachets across several flavours, made in Canada. The sensible way to find out whether electrolytes do anything for you before committing to a full tub of one flavour you might not like.
Magnesium Bisglycinate 200mg
The electrolyte everyone forgets. Magnesium is lost in sweat in far smaller amounts than sodium, but intakes are commonly below recommendations to begin with — and cramping, poor sleep and general fatigue are the symptoms people wrongly blame on dehydration.
Organic MCT Oil Powder
Medium-chain triglycerides are absorbed and oxidised more directly than long-chain fats, which is why they raise blood ketones and get used as a keto energy source. The powder is far kinder to the stomach than straight oil. A fuel, not a fat burner — treat the weight-loss claims sceptically.
Which one is right for you
If you are in the first two weeks of a ketogenic or very low-carb diet, this is the clearest use case on the page. Cutting carbohydrate lowers circulating insulin, and lower insulin prompts the kidneys to excrete sodium and water — which is why the early "keto flu" cluster of headache, fatigue, light-headedness and cramping tracks so closely with sodium loss. Replacing sodium deliberately during that transition addresses the actual mechanism.
If you sweat heavily, train in heat, or do sessions over about ninety minutes, an electrolyte drink is doing real work. Below that duration, in a climate-controlled gym, water is almost always sufficient and the electrolyte powder is a preference rather than a need.
If you are a salty sweater — white residue on your cap and clothing, stinging eyes, a persistent tendency to cramp late in sessions — you are likely at the high end of the sodium loss range and a higher-sodium product is worth the cost.
If you are just at a desk, you almost certainly do not need this. A normal Canadian diet already supplies more sodium than most people require, and electrolyte powders are not a general wellness product.
If you have high blood pressure, kidney disease, or heart failure, or take a diuretic or a potassium-sparing medication, talk to a physician before adding a high-sodium or potassium-containing supplement. Deliberately raising these intakes is not neutral if you are managing any of those conditions.
Frequently asked questions
What is “keto flu”, really?
A cluster of symptoms — headache, fatigue, irritability, light-headedness on standing, muscle cramps — that commonly appears in the first week or two of a sharp carbohydrate reduction. The main mechanism is not carbohydrate withdrawal in any dramatic sense; it is fluid and sodium loss. Lower carbohydrate intake lowers insulin, lower insulin reduces sodium reabsorption in the kidney, and sodium leaves with water. Most of the syndrome is dehydration and sodium depletion wearing a branded name, which is why deliberately replacing salt and fluid tends to resolve it quickly.
How much sodium do I actually need to replace?
It depends heavily on how much you sweat and how salty your sweat is, both of which vary several-fold between individuals. Sweat sodium concentration commonly falls somewhere in the range of 400–1500mg per litre, and an hour of hard training in heat can cost well over a litre of sweat. Practically: start at the lower end, increase if you still cramp or feel flat late in sessions, and pay attention to whether you leave salt marks on your clothing.
Can you drink too much water?
Yes, and it is the reason this category exists. Exercise-associated hyponatremia occurs when large volumes of plain water dilute blood sodium, and it is genuinely dangerous — endurance events have recorded fatalities from it. It is far more common in slower marathon and ultra participants who drink at every station than in fast ones. The symptoms overlap confusingly with dehydration: headache, nausea, confusion. The distinguishing signals are drinking a lot and not urinating much, or gaining weight over a long event. Drinking to thirst, with sodium, rather than on a fixed schedule is the standard advice.
Do I need electrolytes for a normal gym session?
Almost certainly not. A 45- to 75-minute indoor session at moderate intensity produces sweat losses that a normal diet and a bottle of water cover comfortably. The case strengthens with duration, heat, humidity, and individual sweat rate. If you finish a standard session and your shirt is barely damp, an electrolyte powder is buying you very little.
Are these better than a regular sports drink?
Different, and better for a specific purpose. A conventional sports drink is built to deliver carbohydrate for fuel, with electrolytes secondary; the products here invert that. If you are doing a long endurance session and need energy, the carbohydrate is a feature and a zero-sugar electrolyte mix leaves you under-fuelled. If you are managing a keto transition or simply want sodium without the calories, the sugar is dead weight.
What is MCT oil powder doing on an electrolyte list?
It belongs to the same low-carb context rather than to hydration. Medium-chain triglycerides are absorbed and metabolised more directly than longer-chain fats and can raise blood ketones, which is why they appear alongside keto products. It is a fuel and satiety ingredient, not an electrolyte, and it will do nothing for cramping or dehydration — worth understanding before you buy it expecting one thing and get the other.
- Baker LB. "Sweating Rate and Sweat Sodium Concentration in Athletes: A Review of Methodology and Intra/Interindividual Variability." Sports Med, 2017;47(Suppl 1):111–128.
- Hew-Butler T, Rosner MH, Fowkes-Godek S, et al. "Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015." Clin J Sport Med, 2015;25(4):303–320. PMID 26102445.
- Tiwari S, Riazi S, Ecelbarger CA. "Insulin's impact on renal sodium transport and blood pressure in health, obesity, and diabetes." Am J Physiol Renal Physiol, 2007;293(4):F974–F984.
- St-Onge MP, Jones PJH. "Physiological effects of medium-chain triglycerides: potential agents in the prevention of obesity." J Nutr, 2002;132(3):329–332.
Educational content only — not medical advice. If you have high blood pressure, kidney disease or heart failure, talk to your doctor before deliberately increasing sodium. Prices last verified 7 August 2026; confirm on Amazon.ca. As an Amazon Associate we may earn from qualifying purchases.