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athleticinsight
Buyer's Guide · Updated June 2026

The Best Electrolytes for Fasting

Most electrolyte drinks are loaded with sugar and calories that quietly break your fast. The right one replaces the minerals you lose, sodium, potassium, and magnesium, without anything that pulls you out of the fasted state. Here is what to look for, and the formula we built to do exactly that.

The short answer

The best electrolyte for fasting is zero sugar, zero calorie, and complete. Athletic Insight Hydration pairs 5 electrolytes with a full B-vitamin complex for clean energy while you fast, with nothing that breaks the fast.

Built for Fasting Athletic Insight Hydration Electrolyte Powder mixed in water
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4.7 · 323 reviews

Athletic Insight Hydration

0g sugar · 0 calories · won't break your fast

water_dropZero Added Sugar
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ecoZero Calories
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timerWon't Break Your Fast
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boltB-Vitamin Energy Support
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verifiedIn-House Tested
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flagUSA Manufactured
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Why electrolytes matter when you fast

When you stop eating, insulin drops. Falling insulin tells your kidneys to flush sodium, and water and other minerals follow it out. That is why the headaches, fatigue, brain fog, and muscle cramps people blame on hunger are usually just an electrolyte shortfall.

Replacing sodium, potassium, and magnesium keeps you feeling normal through a fast. The catch is that most electrolyte drinks fix one problem and create another: they pack in sugar and calories that spike insulin and pull you straight out of the fasted state.

So the bar for a true fasting electrolyte is simple. It has to replace the minerals you are losing without adding anything your body has to digest.

What to look for

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Zero sugar & calories

Anything you have to digest can trigger insulin and break the fast. Sugar, dextrose, and maltodextrin are out.

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The 3 key minerals

Sodium, potassium, and magnesium are the three you lose fastest. A complete formula covers all of them.

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Energy without food

B vitamins help convert stored fuel into energy, so you stay sharp through the fast without eating a thing.

The Formula

The best electrolyte for fasting

Athletic Insight

Hydration Electrolyte Powder

star star star star star
4.7 · 323 reviews

Why it works for fasting: it keeps you fully fasted and supports energy. Zero sugar, zero calories, five electrolytes in highly absorbable citrate form, and a complete B-vitamin complex most electrolyte drinks leave out.

  • check_circle0g sugar, 0 calories so it never breaks your fast
  • check_circle5 electrolytes (sodium, potassium, magnesium, calcium) in citrate form, gentle on an empty stomach
  • check_circleFull B-vitamin complex for clean energy while fasted
  • check_circleActually tastes good so daily fasted hydration is easy to stick to
Athletic Insight Hydration Electrolyte Powder pouch
$34.99
One-time purchase

$15.01 away from free shipping.

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The Formula

What's in every serving

Five electrolytes in gentle citrate form, plus a full B-vitamin complex. Everything your body loses while fasting, and nothing it has to digest.

Sodium

100mg

Sodium Citrate

The mineral you shed fastest once insulin drops. Replacing it stops the headaches and fatigue people blame on hunger.

Potassium

200mg

Potassium Citrate

Works with sodium to keep muscles firing and prevent the cramps that show up on longer fasts.

Magnesium

20mg

Magnesium Citrate

Drives energy production and muscle relaxation, in a citrate form your body actually absorbs.

Calcium

40mg

Calcium Citrate

The fourth core electrolyte most formulas skip, supporting nerve signalling and muscle contraction.

B Vitamins

B1–B12

Full B Complex

Help turn stored fuel into clean energy, so you stay sharp through the fast without eating a thing.

Citrate Forms

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Gentle Absorption

Every mineral uses the citrate form, which absorbs efficiently and sits easy on an empty stomach.

0gSugar
0Calories
0gNet carbs
Why It Wins

Built for the fasted state

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Energy without food

A full B1–B12 complex helps turn stored fuel into usable energy, so you stay sharp deep into the fast.

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5 electrolytes

Sodium, potassium, magnesium and calcium cover every mineral a fast depletes, not just one or two.

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Gentle citrate forms

Citrate minerals absorb efficiently and sit easy on an empty stomach, unlike harsh chloride or oxide forms.

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Nothing that breaks it

Zero sugar, zero calories, zero net carbs. Keto, OMAD and intermittent fasting all stay intact.

Simple Routine

How to use electrolytes while fasting

1

Start in the morning

Mix one scoop into a large glass of water when you wake. This front-loads minerals before the most common mid-morning fasting slump.

2

Spread it through the day

On longer fasts you can have a second serving in the afternoon. Steady mineral levels feel far better than one big dose.

3

Add a pinch of salt if you fast long or hard

For 24-hour fasts or heavy training, a little extra sodium on top covers the higher losses without breaking anything.

Verified Reviews

What fasters are saying.

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"I do 18:6 every day and this killed the mid-morning headaches I always blamed on hunger. No sugar, no crash."

Marcus T. · Verified Buyer

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"The B vitamins are the difference for me. I actually have energy on fasting days now instead of dragging."

Priya S. · Verified Buyer

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"Other electrolyte mixes were too salty on an empty stomach. This is way easier to drink first thing."

Dana R. · Verified Buyer

Illustrative customer feedback. Replace with the live Judge.me widget when published to Shopify.

Fasting electrolyte FAQs

Do electrolytes break a fast? expand_more
Pure electrolytes do not. Sodium, potassium, and magnesium have no calories and do not raise insulin, so they keep you fully fasted. What breaks a fast is the sugar and calories added to many electrolyte drinks. A zero-sugar, zero-calorie formula like Athletic Insight Hydration keeps you in the fasted state.
Is the sucralose a problem for fasting? expand_more
For the vast majority of people, no. Sucralose has zero sugar and zero calories and does not raise blood glucose, so it keeps your fast intact for fat loss and metabolic benefits. If you follow a strict autophagy or zero-sweetener protocol, you can simply take it during your eating window instead.
How many servings can I have while fasting? expand_more
One serving in the morning is enough for most intermittent fasting windows. On longer or 24-hour fasts, a second serving in the afternoon helps keep mineral levels steady. Since there are no calories, extra servings will not break your fast.
Can I add it to black coffee or tea? expand_more
Yes. Many people add electrolytes to water alongside their morning coffee. It is best mixed into water rather than into the coffee itself, so you stay hydrated and the flavor stays clean.
Is the sodium dose enough for fasting? expand_more
For everyday intermittent fasting, yes. The balanced dose replaces what you lose without the unpleasantly salty taste of mega-dose formulas on an empty stomach, and it comes alongside potassium, magnesium, calcium, and a full B-vitamin complex. If you run 24-hour fasts or train hard while fasted, a pinch of extra salt tops you up easily.
Fast Clean

Stay fasted. Stay energized.

Replace what fasting depletes without breaking your fast. Five electrolytes, a full B-vitamin complex, zero sugar.

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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. Consult your healthcare provider before fasting if you are pregnant, nursing, or managing a medical condition.