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This science-backed 3 day protocol is designed to fuel your body, boost mental clarity, and help you feel your best without deprivation. With everything you need in one box, FastBurnBox makes fasting simple, effective, and energizing. Most users lose 4–6 pounds – without starving.
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FastBurnBox takes the guesswork out of fasting by giving you everything you need in one simple kit. Backed by science and designed by experts, it combines nutrient-rich broths, fiber for satiety, and electrolytes to keep you hydrated and energized – so you're never running on empty.
Unlike extreme cleanses or DIY fasts, FastBurnBox is structured to support your body with real nourishment while promoting fat burning, reducing bloating, and improving metabolic health. You'll feel mentally sharp, physically lighter, and more in control – all without starving or feeling deprived.
Electrolyte booster (lime) supplement facts
Serving size 1 packet (11 g). Calories 15. Calcium (as calcium lactate) 300 mg (23% DV). Phosphorus (as potassium phosphate) 370 mg (30% DV). Magnesium (as magnesium citrate) 140 mg (33% DV). Chloride (as sodium chloride) 600 mg (26% DV). Sodium 640 mg (28% DV). Potassium 820 mg (17% DV).
Other ingredients: crystallized lime (citric acid, lime oil, lime juice), citric acid, stevia leaf extract, inulin. Allergens: none. Suggested use: add 1 packet to 16 fl oz (480 ml) water and mix well.
Fiber shake (grapefruit)
Serving size 1 packet (7.3 g). Calories 30. Total fat 0.5 g. Total carbohydrate 5 g. Dietary fiber 3 g. Sodium 30 mg. Psyllium husk 4 g. Flaxseed powder 1 g.
Other ingredients: crystallized grapefruit, stevia leaf extract, rice hulls, sea salt, citric acid. Allergens: none. Suggested use: add 1 packet to 14-16 fl oz (420-480 ml) water and mix well.
Notice: this food should be eaten with at least a full glass of liquid. Eating this product without enough liquid may cause choking. Do not eat it if you have difficulty swallowing.
Bone broth
Serving size 1 packet (9.2 g). Calories 30. Total fat 1 g. Saturated fat 1 g. Total carbohydrate 1 g. Dietary fiber 1 g. Protein 3 g. Sodium 500 mg (22% DV). Potassium 100 mg (2% DV). Chicken bone broth 5 g.
Other ingredients: sea salt, natural flavor, coconut MCT oil powder, organic rice hulls. Allergens: tree nuts. Suggested use: add 1 packet to 8-10 fl oz (240-300 ml) warm water or soup.
Percent daily values are based on a 2,000-calorie diet. Confirm these panels against the product you actually ship before publishing.
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Because your body doesn't need more restriction – it needs a reset. We live in a world full of processed foods, blood sugar crashes, constant snacking, and non-stop stress. Over time, this overwhelms your system, slows your metabolism, and makes it harder to feel in control of your health.
That's why you're stuck with bloating, stubborn weight, and fatigue. FastBurnBox breaks the cycle with a guided 3-day fast that restores balance, supports digestion, and kickstarts fat burning – without deprivation.
FastBurnBox activates one of your body's most powerful built-in tools: autophagy – the natural process of cellular cleanup and repair that happens during fasting. When you pause constant digestion, your body finally gets the chance to clear out damaged cells, reduce inflammation, and restore balance at a deep cellular level.
FastBurnBox is a full-body reset. You'll feel the difference – less bloating, more energy, better focus, and a renewed sense of control.
If you fast for an extended period unprepared, it can disrupt the normal pattern of your circadian rhythm – your internal clock carrying out essential body functions. If disturbed, it can lead to poor sleep, low energy levels, and hormonal imbalances. FastBurnBox unique blend of supplements helps your body to maintain or even improve your circadian rhythm.
When fasting, your body quickly runs through a small reserve of its electrolytes. Electrolytes are minerals essential for the normal functioning of almost all of your body's systems and organs. You may experience headaches, fatigue, or muscle cramps if fasting carelessly. FastBurnBox supplements will replenish your electrolytes to keep your body hydrated and avoid unpleasant side effects.
If you're negligent about your fasting preparations, it can deplete your body's vital minerals, vitamins, and amino acids. You may feel tired and weak after your first day. To prevent that, certified dietitians at FastBurnBox created a unique blend of supplements. It supplies your body with all the essential nutrients to maximize the benefits of your program.
If you rush into prolonged fasting unprepared, you may shock your gut and experience digestive problems like constipation, bloating, and stomach aches. That's why your FastBurnBox program includes supplements specifically designed to support your digestive system during fasting.
Hour by hour
Your body does not flip a switch at hour one. It shifts gears. Here is the general rhythm most people notice, so you know what is normal and when the hard part usually passes.
Your body is still working through the food you just ate, so energy comes straight from that plate. Nothing dramatic yet. The clock has started and your job is simply to stop grazing.
Digestion winds down and your body begins leaning on stored energy instead of incoming food. Most people feel completely normal here, maybe a little clearer once the post-meal dip passes.
This is where habit hunger shows up, usually right around the times you normally eat. It tends to arrive in waves and pass in twenty minutes. Water, black coffee or tea, and a walk carry most people through it.
Stored carbohydrate is running low, so your body starts drawing more of its energy from fat. Many people describe this stretch as steady focus without the usual mid-afternoon crash.
The fuel switch is well underway and appetite often quiets down rather than climbing. Keep fluids and electrolytes up here, because a lot of what feels like hunger is really mild dehydration.
Research suggests longer fasts give the body room to run its natural cleanup and repair processes. You will not feel this happening, and that is exactly the point.
An advanced window that experienced fasters use occasionally, not daily. Energy is usually stable, but this is the stage to be honest with yourself and stop if you feel unwell.
Open with protein, fibre and something easy on the stomach rather than the biggest meal you can find. How you break the fast decides how good the next twelve hours feel. Burn fat, not your health.
Timings vary from person to person. This is general wellness information, not medical advice. Talk to your doctor before fasting if you are pregnant, managing a health condition, or taking medication.
Find your fasting windowClinically-Supported Support for Prolonged Fasting
A soluble prebiotic fiber that gently supports digestion and satiety.
Helps promote a feeling of fullness without breaking your fast, reducing hunger pangs and improving compliance.
Supports gut microbiome balance and helps regulate bowel movements, which can slow during extended fasts.
Essential minerals that maintain hydration, nerve function, and energy levels.
Replenishes minerals lost through urine and sweat, preventing fatigue, headaches, muscle cramps, and the dreaded "keto flu."
Key to supporting blood pressure, heart function, and physical performance when no food is consumed.
A nutrient-rich broth made from slow-simmered bones, rich in collagen, amino acids, and minerals.
Offers a gentle, low-calorie way to nourish your body, support gut lining integrity, and provide joint and skin support—all without spiking insulin.
Glycine and glutamine in bone broth help reduce gut inflammation, improve sleep quality, and support detox pathways.
These supplements are your essential toolkit for a successful prolonged fast:
Together, they turn your fast from a struggle into a high-performance metabolic reboot.
Diet and exercise alone can't fully refresh your body. Prolonged fasting triggers autophagy—your cells' natural cleanup process where they break down and recycle damaged components to stay healthy and efficient. This process boosts fat burning and supports longevity. Without it, lasting weight loss and health improvements stay out of reach.
Your body's hormone network is complex—diet and exercise alone aren't always enough to reset it. FastBurnBox uses the power of prolonged fasting to activate deep cellular repair, rebalance insulin sensitivity, and unlock fat loss and longevity at the root.
Real stories of change. Here's what you can look forward to.
I've fasted periodically over the last year with this kit and lost 16 lbs. The energy I have is incredible! The bone broth really helped me stay comfortable during the fast.
I'd considered myself somewhat experienced with fasting but I wanted to try out this kit and see what all the hype is about. So far my longest fast and it wasn't even all that hard, the sachets and info provided really helped!
Honestly went in with low hopes - "fasting kits" always scream gimmick. But after three 20-hour fasts I felt steady, no crashes, no shaky hands. The electrolyte stick tastes kinda like diluted lemonade (in a good way) and the guide kept me on track.
Nice customer support answered a few of my queries, smooth ordering experience, and the product itself is without a fault. Happy with my purchase and fasting experience.
Don't sweat it! We've got a delicious strawberry-flavor fiber drink that will keep you feeling full without messing up your fast because it’s practically zero calories.
Actually, most folks find they get a nice energy boost during fasting because your body doesn't have to deal with digesting food. Plus, we'll show you what to do before your fast so your body has plenty of energy in the reserves to weather the fast.
Don't stress! We'll show you how to avoid common mistakes that lead to keto flu. Stick to it, and you won't have to deal with those nasty symptoms.
No worries! You can easily order a refill. Or you'll get a refill automatically with our 6-month or 12-month plans (just have to wait a bit). That said, you can also fast without a fiber shake – it's totally doable and many of our customers love the challenge.
Totally get it! We suggest planning your fast for a long weekend or during a holiday when you have more freedom in your schedule. Sure, it might be a bit inconvenient, but remember, it's your health we're talking about here – maybe it's worth the effort?
Generally, yes, but it depends. If you've got diabetes, you should chat with your doctor first since it can mess with your blood sugar. For those who are pregnant or breastfeeding, it's usually a no-go because your body needs extra food for the little one. Best to check with a healthcare pro to be sure fasting's cool for you!
A 3-day fast like FastBurnBox can be more straightforward and impactful than fasting-mimicking or intermittent fasting. Here's why: Simplicity: With a 3-day fast, you have a clear start and end. There's no need to constantly plan meals or watch the clock for eating windows, which you often have to do with fasting-mimicking or intermittent fasting. Intensity and Results: A full 3-day fast can kickstart significant metabolic changes in a short period. It's like a hard reset for your system, potentially leading to more noticeable results compared to the gradual approach of intermittent fasting or the partial fasting of fasting-mimicking plans.
Glucomannan is the key ingredient, it absorbs water and keeps you full during your fast, which helps with hunger pangs. Plus, it's only 10 calories, so it won't mess up your fast.
Your FastBurnBox is going to be dispatched within 3–5 business days. There, you will find everything you need to make the most of your experience and achieve your goals.
The FastBurnBox program is meant to support general health. Use it as part of a healthy lifestyle. If at any point you feel unwell, please consult a qualified healthcare professional.