Rawstone Learn
Plain-English guides to sodium, electrolytes and hydration. No jargon, no medical claims, just the physiology explained the way we wish someone had explained it to us. General education, not medical advice.
Five checks, about a minute: sodium per serve, sugar, the sweetener grade, the magnesium form, and whether each batch is lab tested.
The ScienceWhy the concentration of sodium in your glass matters more than the milligrams printed on the pack.
SodiumThe calm, plain-English context behind a number that looks big at first glance, and how to start with half.
MineralsThe same milligram number can behave very differently, because the form decides how much your body absorbs.
TasteWhy the cheap stevia grade leaves a bitter aftertaste, and what the cleaner grades cost to use instead.
FastingZero-calorie minerals carry no energy, so the honest answer comes down to the rest of the ingredient list.
KetoWhy cutting carbs flushes more salt through your kidneys, and what the flat, foggy keto-flu feeling often comes down to.
Put in how long you trained and how hard you sweated, and get a rough idea of how much sodium left your body and roughly how many serves that is worth putting back. There is a printable one-page cheat sheet too.
Open the sweat calculator → Get the cheat sheet