Extended Fasting

Extended Fasting

The length of a healthy water fast can vary depending on an individual's health, medical history, and overall condition. Generally, short-term water fasting for 24 to 72 hours can be safe for many people and may provide certain health benefits, such as improved metabolism, reduced inflammation, and enhanced cellular repair processes.

A friend of ours, @HaroldisFasting is on a 45 day water fast for health and religious reasons. He's crushing it, and also tracking his body's progress along the way. Check out the journey on TikTok at https://www.tiktok.com/@haroldisfasting. 

You'll see that on DAY NINE (!!) Harold drinks fasting hydration FAST:RX as a treat and for ultra hydration - because it doesn't break his fast and can help him get through a little easier. One day at a time!

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Frequently Asked Questions

Does FAST:RX break a fast? 

No — FAST:RX is completely fasting-safe. It contains zero sugar, zero calories, and no ingredients that trigger an insulin response,
so you can drink it throughout your entire fasting window without interrupting
fat burning or ketosis.




What can I drink during intermittent fasting? 

Water, black coffee, plain tea, and fasting-safe electrolyte drinks are all compatible with intermittent fasting. FAST:RX is
specifically formulated for fasting — it replenishes your electrolytes without
any sugar or calories that would break your fast.

Why do I feel tired and hungry while fasting? 

Fatigue and hunger during fasting are most often caused by electrolyte depletion, not true caloric need. When sodium, magnesium, and potassium drop, your body sends hunger and fatigue signals. Replenishing electrolytes with FAST:RX can dramatically reduce these symptoms without breaking your fast.

Do electrolytes break a fast? 

No — electrolytes in their pure form contain no calories and do not trigger insulin. FAST:RX delivers sodium, potassium, and
magnesium in a completely fasting-safe formula, making it the ideal companion
for any fasting protocol.

What is the best electrolyte drink for fasting? 

The best electrolyte drink for fasting is one with no sugar, no artificial sweeteners, and no calories — formulated specifically for
the fasting state. FAST:RX was built from the ground up for fasters, with the
exact electrolyte balance your body needs during a fasting window.

How do I stop feeling dizzy when fasting? 

Dizziness during fasting is almost always a sign of low sodium or magnesium. Drinking plain water can actually make this worse by
further diluting your electrolytes. The fix is to add electrolytes — FAST:RX is
designed to restore balance quickly so you can get through your fast feeling
clear and energized.

Is intermittent fasting safe? 

Intermittent fasting is safe for most healthy adults and is backed by a growing body of research showing benefits for metabolic
health, weight management, and longevity. Always consult your doctor if you
have underlying health conditions. Supporting your fast with proper hydration
and electrolytes like FAST:RX makes it safer and more sustainable.