If you follow our videos on YouTube and other blogs, then you know that we are huge advocates of regular fasting. Humans have fasted for thousands of years, and it is the easiest ways to cut calories and burn fat fast. While intermittent fasting windows like 16:8 are great and highly recommended, completing a full 24-hour fast can offer unique benefits and a deeper reset for your system.
If you are curious about attempting a 24-hour fast, this guide will walk you through the why and the how, ensuring you approach it safely and effectively.
Disclaimer: We are not doctors. This content is for informational purposes only. You should consult a healthcare professional before making significant changes to your diet or attempting extended fasting, especially if you have underlying health conditions or a history of disordered eating.
Why Fast for 24 Hours?
Before diving into the logistics, it is helpful to understand what happens to your body when you stop eating for a full day. While weight loss is a common motivation, the physiological impacts go much deeper.
Metabolic Flexibility
One of the primary benefits of fasting is improved metabolic flexibility. This is your body's ability to switch from burning glucose (sugar) for fuel to burning fat. When you eat frequently, your body relies constantly on the glucose from your last meal. After about 12 to 16 hours of fasting, glycogen stores in the liver begin to deplete, and the body must start mobilizing stored body fat for energy (Mattson et al. 192). A 24-hour fast pushes you deeper into this fat-burning state than shorter fasting windows.
Cellular Cleanup (Autophagy)
Perhaps the most exciting benefit of fasting is a process called autophagy. Think of this as your body’s internal recycling program. When cells are not busy processing nutrients, they turn inward to clean house. They break down and recycle damaged proteins and organelles. Research suggests that autophagy may play a critical role in protecting against neurodegenerative diseases and aging (Longo and Mattson 466).
How to execute a 24-Hour Fast: A Step-by-Step Plan
A 24-hour fast sounds daunting, but it is actually quite manageable if you structure it correctly. Our recommendation is the "Dinner-to-Dinner" approach.
Step 1: Choose Your Window
The psychological hurdle of going a whole day without eating is easier if you sleep through a large portion of it. If you finish dinner between 6:00 and 7:00 PM on Tuesday, you simply don't eat again until 7:00 PM on Wednesday. This way, you still eat every single day—you just skip breakfast and lunch on Wednesday.
Picking a weekend day when you can sleep for 8-10 hours makes it even easier. My personal preference is Friday evening to Saturday evening.
Step 2: The Pre-Fast Meal
Your last meal before the fast sets the tone. Do not binge. Eating a massive meal loaded with sugar and refined carbohydrates. This will spike your insulin and lead to a crash a few hours later, making the fast much harder. Instead, aim for a balanced meal with:
- Protein: Chicken, fish, tofu, or steak.
- Healthy Fats: Avocado, olive oil, or nuts.
- Fiber: Plenty of vegetables.
This combination will keep your blood sugar stable and help you feel satiated longer.
Step 3: Hydration is Key
You cannot eat, but you absolutely must drink. Water is your best friend during a fast. Dehydration often mimics hunger, so if you feel a pang in your stomach, drink a glass of water first. Sipping on fluids also helps keep hunger at bay.
Acceptable liquids during a strict water fast include:
- Plain water (still or sparkling).
- Black coffee (no sugar, milk, or cream).
- Unsweetened tea (green tea is excellent for suppressing appetite).
- Mineral water or water with a pinch of sea salt (to maintain electrolytes).
Step 4: Breaking the Fast
When the 24 hours are up, resist the urge to raid the pantry. Your digestive system has been resting. Hitting it with a heavy, greasy meal can cause stomach distress. Break your fast gently with a small snack—like a handful of almonds, some bone broth, or a small salad—about 30 minutes before your main meal. Then, eat a normal-sized, nutritious dinner.
Tips for Success
Even with a plan, the middle hours of a fast can be challenging. Here is how to navigate the rough patches.
Stay Busy
Boredom is the enemy of fasting. If you are sitting on the couch thinking about not eating, you will be miserable. Schedule your fast on a busy work day or a day full of errands. When your mind is occupied, you will be surprised how easily you can forget about lunch.
Ride the Waves
Hunger is not a linear sensation that gets worse and worse until you explode. It comes in waves. It is often triggered by the hormone ghrelin, which spikes at your usual mealtimes (top of the morning, noon, and evening). If you feel intense hunger, acknowledge it, drink some water or eat a pinch of salt.
Listen to Your Body
There is a difference between discomfort and distress. Feeling hungry or a little foggy is normal. However, if you feel dizzy, faint, shake uncontrollably, or feel ill, stop the fast immediately. There is no prize for suffering. You can always try again another day.
Electrolytes Matter
If you get a headache, it is often due to a lack of sodium rather than a lack of food. When insulin levels drop during a fast, the kidneys excrete more sodium. Adding a pinch of salt to your water or taking an electrolyte supplement (free of sugar and sweeteners) can often cure a fasting headache instantly.
#CUTSZN Challenge
January is fat loss season aka #CUTSZN. We are doing a group challenge through our fitness portal that will include a workout program, meal plan, and weekly fasting and ab workout challenges posted by Coach Kevin. The challenge includes a weekly 24 hour fast. If you want to participate, sign up for our fitness portal. One month is just $14.95. Lets see how much holiday blubber we can shed as a team in 2026.
Want to participate? Click here to get started.
Works Cited
Longo, Valter D., and Mark P. Mattson. "Fasting: Molecular Mechanisms and Clinical Applications." Cell Metabolism, vol. 19, no. 2, 2014, pp. 181-192.
Mattson, Mark P., et al. "Impact of Intermittent Fasting on Health and Disease Processes." Ageing Research Reviews, vol. 39, 2017, pp. 46-58.
