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The Cramps Showed Up on Day Four and I Wasn't Ready
That's what a coaching client told me when she reached out in her first week on carnivore. Her legs woke her up at 3 AM with cramping bad enough that she nearly quit the diet entirely. She didn't need motivation. She needed electrolytes and she needed them explained properly.
"Eat more salt" is what most beginners get told. It's not wrong, but it's incomplete. And the gap between what people are told and what they actually need is why cramps and fatigue are the most common complaint in the first 30 days of carnivore.
Why Electrolytes Get Depleted So Fast
When you cut carbohydrates, insulin drops. Insulin does a lot of things, and one of them is signal the kidneys to retain sodium. When insulin falls, the kidneys start excreting sodium more aggressively. Sodium brings water with it. That's the "water weight" people lose fast in the first week.
Here's the problem: sodium also pulls other electrolytes with it. As your body flushes sodium, it takes potassium and magnesium along for the ride. Add in the fact that most people come to carnivore from a standard diet where they were relying on plant foods for a good portion of their potassium and magnesium, and you've got a setup for a significant electrolyte deficit within days.
Keto folks know this exact crash as the keto flu, and the shape of it is almost identical on carnivore.
The usual picture is muscle cramps, especially in the legs and feet at night, headaches, fatigue that feels different from ordinary tiredness, and brain fog that doesn't lift. If that's familiar in your first few weeks, you're not failing at this, and food and seasoning are a sensible place to start looking.
Heart palpitations get their own paragraph rather than a place on that list. A racing or skipping heartbeat is not something to answer by adding minerals, because too much potassium and too little potassium both cause it and they feel the same. Ring your doctor and tell them you've recently changed how you eat. If it turns up with chest pain, breathlessness or fainting, that's urgent care today.
Before Any of This: The One Question to Settle
Sodium and potassium are the two minerals where the right answer depends on things a blog post cannot see. If you take a daily pill for your blood pressure or your heart, a water pill, or anything to do with your kidneys, ask your doctor or your pharmacist before you increase either one. That includes salt substitutes like Lite Salt or No Salt and it includes electrolyte packets, because some of those medicines already hold potassium in your body and extra on top is the problem rather than the help. Have the same conversation if a blood test has ever come back with a note about your sodium, your potassium or your kidney function, or if anyone has ever told you to watch your salt. If you're not sure whether that's you, that's a reason to ask rather than to assume it isn't.
Sodium: More Than You're Used To, and Best Judged by Taste
Standard sodium guidance was built around high-carbohydrate diets, where insulin keeps the kidneys holding on to sodium without you doing anything. Cut the carbohydrate and that retention signal weakens, so more goes out than you're used to. That's the mechanism, and it's the genuinely useful thing to understand here.
What I'm not going to do is print a daily milligram target, because the readers who'd be harmed by one are the readers least likely to know it applies to them. Salt your food until it tastes right to you, and expect your taste for salt to climb over the first couple of weeks. Salted bone broth is a pleasant afternoon habit and it's food rather than a dose. If you'd like targets set against your own weight, activity and medication list, that's what a conversation with your own clinician is for.
Timing is worth knowing about. If cramps are waking you, sodium tends to drift down overnight, and a small cup of salty broth in the evening is a reasonable, food-shaped thing to try.
One thing I've taken out of this page on purpose. It used to say that if you feel dizzy standing up you should add more salt before you assume something else is wrong. That's backwards. Dizziness on standing has plenty of causes, several of them worth a look, and it is a common reason a blood pressure medication needs adjusting after a diet change. Mention it to your doctor rather than salting past it.
Magnesium: The Most Overlooked Piece
Magnesium is where most beginners go wrong, partly because they don't think about it at all, and partly because when they do try to supplement, they pick the wrong form.
Magnesium oxide is the most common form in cheap supplements and the hardest one for your body to absorb, at around 4%. At that rate you'd need a large amount to move your levels at all, and you'd get digestive trouble long before you got there. That's the useful thing to know when you're standing in the supplement aisle.
Magnesium glycinate is the form I'd look for instead. It absorbs well, it's gentle on digestion, and it reaches the nervous system, which is why people notice it in their sleep. Magnesium malate is another reasonable option if flat fatigue is your main complaint. Evening is the sensible time to take either one.
How much is right for you is not something I can set from here, because it depends on what else you take. Ask your pharmacist, who can see your actual list, and buy the smallest bottle first. If you notice nothing after a fortnight, it wasn't your lever and there's no sense escalating it.
Beef and salmon carry some magnesium, though probably not all you need, so this is the one mineral where a supplement is often a reasonable idea rather than a reflex.
Potassium: This One Comes Off the Plate
Potassium is the one where I want you to be careful, and the reason is specific rather than vague. Too much and too little both affect heart rhythm, and they feel the same from the inside. That's why I'm not going to print a daily potassium target on this page, and it's why the 99 mg on a supplement label doesn't settle anything either: that number is a serving size the industry chose for itself, not a dose measured against your blood. A target invites you to close the gap, and closing a potassium gap with a supplement or a salt substitute is the move that goes wrong.
The good news is that carnivore food carries a useful amount of it. Ground beef has roughly 300 mg per 4 oz. Salmon has about 500 mg per 6 oz. Beef liver is one of the best sources at around 380 mg per 3 oz. Eggs contribute a little.
Practically, eating a pound and a half to two pounds of varied animal food a day, with liver about once a week, gets most people somewhere sensible without any arithmetic. If cramps are hanging around despite decent seasoning and enough food, the first thing I look at is whether someone is simply eating too little overall, and the second is a conversation with their doctor rather than a bigger supplement.
I used to recommend a measured amount of cream of tartar here as a low-risk way to top up potassium, and I've removed it. Cream of tartar is potassium in a baking wrapper, which is the most misleading packaging a supplement can have, and a teaspoon measure of it is a dose whatever the tub says. If you take an ACE inhibitor, an ARB, or a potassium-sparing diuretic, or your kidney function has ever been flagged, that is exactly the kind of thing your body was already holding onto for you.
A Practical Place to Start
- Season your food until it tastes right to you, at every meal, and let your taste for salt climb over the first fortnight.
- Have a cup of salted bone broth most days in the first couple of weeks. It's food, it's pleasant, and it's self-limiting in a way a measured glass isn't.
- Eat at least a pound and a half of varied animal food a day, with liver about once a week. That's the potassium handled.
- Eat enough. Under-eating causes a lot of what gets blamed on minerals, and it's the first thing I check.
- If you're going to try magnesium, ask your pharmacist what's sensible alongside anything else you take, and take it in the evening.
- If cramps are waking you night after night, or they're one-sided, or the leg is swollen or hot, that's a doctor rather than a bigger dose.
Most people see significant improvement within 48 to 72 hours of dialing in these three electrolytes. The carnivore diet doesn't cause cramps and fatigue because it's harmful. It causes them because the dietary transition changes how your kidneys handle minerals, and nobody warned you to compensate for that shift.
Getting your food variety right also helps naturally, since a range of animal foods covers more nutritional ground than eating only ground beef every day. And if you're dealing with ongoing fatigue beyond the first month, it's worth ruling out thyroid factors that can masquerade as electrolyte issues.
Season your food. Eat enough. Give it two or three weeks. For most people in their first month, that's the whole of it.
And if it isn't, that's information rather than failure. Cramps that don't settle, dizziness on standing, or a heartbeat that feels wrong are all worth a proper look, and none of them are worth more salt.
I'm not a doctor. I've researched this deeply and worked with a lot of people through their first month, but I'm not your doctor. If you take medication for your blood pressure, your heart or your kidneys, or a water pill, or anyone has ever told you to watch your salt, sodium and potassium are theirs to set rather than mine. Everything here is educational. Your situation might be different.