How much sodium do you need on keto?

On a low-carb diet most people need roughly 4,000–5,000 mg of sodium a day — about two teaspoons of salt all in, counting what is already in your food. That is two to three times the cap on a public-health leaflet, and it is not a mistake: cutting carbohydrate lowers insulin, low insulin tells your kidneys to let sodium go, and at the same time dropping bread, sauces and packaged food quietly removes most of the sodium you used to eat without noticing. Both happen in the same week, which is why beginners feel terrible on a diet that is otherwise working.

Why the usual guidance doesn't apply

The familiar 2,300 mg-a-day ceiling is written for a population eating a normal amount of carbohydrate. Insulin is not only a glucose hormone; it also acts on the kidney tubule to reabsorb sodium. Eat carbohydrate at most meals and insulin stays elevated enough, often enough, that your kidneys hold onto sodium for you in the background. That retention is the hidden assumption behind the advice.

Drop carbohydrate under about 50 g a day and insulin falls to a low baseline. The retention signal goes with it and sodium leaves in urine, pulling water along — which is a large part of the fast scale drop in the first week. You are no longer banking sodium between meals; it has to go in by mouth.

The second half is subtraction. Most sodium in a typical diet comes from packaged and restaurant food, not the salt shaker: bread, deli meat, sauces, dressings, chips, takeout. Low-carb eating deletes that category in one go, so people assume they are salting more because the shaker comes out more often, while their daily total has fallen by thousands of milligrams.

What you're really getting from whole food

Fresh, unsalted animal food is a poor sodium source. Approximate values:

A carnivore day of unsalted steak and eggs can land under 1,000 mg. That is the gap you are closing, and it is why carnivore eaters usually need the most deliberate salting, with ketovore and keto behind them.

The signs you're under

• Light-headedness or a grey-out when you stand up quickly — the clearest single sign, because blood volume follows sodium
• Headache, often dull and all-day rather than sharp
• Calf and foot cramps, especially at night
• Fatigue that lands in the afternoon, and workouts that feel heavier than the weight on the bar
• A real craving for salty food — worth trusting on a low-carb diet rather than overriding
• Heart palpitations or a fluttering feeling
• Constipation, from less water held in the gut

These are the symptoms of keto flu, which largely is this problem arriving all at once in week one. The difference: the sodium need does not end after week one. It lasts as long as you eat this way.

How to actually hit the number

1. Salt your food properly. A few weeks in, taste is a fair guide: food that tastes flat usually is.
2. Use broth as the base layer. A cup in the morning covers 500–1,000 mg before the day starts, and it is the easiest habit to keep.
3. Keep a glass-of-water option. A quarter teaspoon of salt in a large glass of water is about 575 mg and fixes an afternoon headache in roughly twenty minutes.
4. Eat the salty whole foods. Pickles, olives, cured meat and hard cheese all count toward the total.
5. Add more for sweat and heat. Sweat carries roughly 500–1,500 mg of sodium per litre, so a hard sweaty hour is another 500–1,000 mg to replace. Training on keto covers the rest.

Front-load it. Most of the dizziness, fog and flat workouts happen in the morning and early afternoon, so sodium taken early does more work than sodium taken at dinner.

Can you overdo it?

Yes, and the feedback is quick: thirst, puffy fingers and face, and a headache indistinguishable from the one you were trying to fix. A big dose at once also tends to cause loose stools, so spread it across the day. Expect salt to move the scale by a pound or two of water either way within a day; that is water, not fat, and it is the most common false alarm behind a suspected stall.

Who needs to be careful

This guidance assumes normal blood pressure and normal kidney function. Deliberately adding grams of sodium a day is a different decision if you have high blood pressure, heart failure, or chronic kidney disease, and a low-carb diet can itself change how much medication you need. None of this is medical advice: if you take blood-pressure medication, a diuretic, or diabetes or kidney medication, talk to your doctor before you start adding salt — and never stop or change a dose on your own.

The short version

1. Low carbs mean low insulin, and low insulin means your kidneys stop holding sodium for you.
2. Aim for roughly 4,000–5,000 mg a day — about two teaspoons of salt, everything included.
3. Whole unsalted meat and eggs supply almost none of it, so it has to be added on purpose.
4. Dizzy on standing is the signal to act; broth in the morning is the easiest fix.
5. Add more on sweaty days, and check with your doctor first if you take the medications above.

The app's daily checklist turns the morning broth into one box to tick, so the sodium habit holds on week six as well as week one — start free.