Plant-based fasting nutrition, built on 25+ years of USC longevity research
Built on 25+ Years of fasting research
Intermittent fasting, without the 3pm crash
You didn't quit because fasting stopped working. You quit because you were running on empty. Our plant-based, pre-portioned nutrition keeps you in a fasting state, so you feel better while the fast keeps going.
From $75 · HSA/FSA eligible · Subscribe and save 15%
★ 4.4 out of 5 · 1M+ customers ·
40+ clinical trials
Researched with
41
Clinical trials
conducted with world-leading institutions
18
Research institutions
including USC, Stanford, Mayo Clinic, and more
130+
Issued patents
supporting longevity and healthspan
25+
Years of research
behind nutrition science that signals the body to fast
The real reason
You didn't stop because it wasn't working. You stopped because you didn't feel well.
Your body doesn't respond to calories alone. It reads signals. Prolon's plant-based foods are formulated from 25+ years of research to stay below the signals that tell your body it's been fed, so you stay in a fasting state while you eat.
Fasting on an empty stomach
- —Energy dips in the afternoon, and that's usually where the window ends
- —The fast breaks on sugar, which switches the fat-burning state off more quickly
- —Hunger and low energy make 5:2 and 6:1 hard to keep up with week after week
- —Nothing nourishes your body in the hours in-between
Fasting with Prolon
- ✓A Fasting Bar at hour 12, clinically shown to keep ketones and blood sugar comparable to a water-only fast
- ✓A 1-Day Reset maintains 24 hours in a fasting state, with science-backed nutrition
- ✓Built for 5:2 and 6:1 routines, with nothing to prep, count or decide
- ✓Formulated from 25+ years of research on how food signals your cells
How it works
Three steps, on your schedule
Clinically backed, pre-portioned nutrition, formulated to keep you in a fasting state while you eat.
Step one
Reset the day
A full 24 hours in a fasting state that supports ketosis, while you still eat. Optimal as part of a weekly 5:2 or 6:1, with pre-portioned, nutritious foods.
Step two
Bridge the window
Eat a Fasting Bar at hour 12 to extend your fat-burning state, with energy and nourishment. No blood sugar spike.
Step three
Repeat on your pattern
Eat normally five days and use the kit the other two, or hold a 6:1. Not sure? Our Build the Habit bundle is where most people start: one reset day, plus bars for fasting mornings.
No prep. No counting. No guesswork. Our fasting-supportive nutrition is formulated, portioned, and ready to eat.
What arrives
Everything your fasting days need
The reset day
Prolon 1-Day Reset Next Gen
A full 24 hours in a fasting state that supports ketosis, while you still eat. The Next Gen kit brings organic soups, kale crackers, Italian olives, nutrient-dense nut bars, and teas, portioned across the day.
- ✓Patented FMD technology from 25+ years of USC Longevity Institute research
- ✓Organic soups, crackers, olives, nut bars and teas, portioned and boxed
- ✓Optimal as part of a weekly 5:2 or 6:1, with nothing to prep or count
The days in between
Fasting Bars
Clinically shown to keep ketones and blood sugar comparable to a water-only fast. Eat one at hour 12 and stay in your fasting state, with nourishment and energy support.
- ✓Variety pack of 12 bars: chocolate chip, coconut macadamia, and nuts and honey
- ✓Formulated to stay below the threshold that tells your cells you are fed
- ✓ Works as a real breakfast at hour 12, or whenever your day needs it
"The easiest way to fast without any hunger."
Lynn Levy
Verified customer · Mar 16, 2026
Individual results vary.
Choose your bundle
Pick your routine
Three bundles, built around how often you fast. Every one pairs the 1-Day Reset with the bars that carry the hours in between.
Save an additional 15% on every delivery. Pause, skip or cancel anytime.
Ease In
1x 1-Day Reset · 1x Fasting Bars
$84.99
$63.75
Save $21.24
Build the Habit
1x 1-Day Reset · 2x Fasting Bars
$119.97
$84.15
Save $35.82
Monthly Practice
4x 1-Day Reset · 2x Fasting Bars
$239.94
$161.50
Save $78.44
Not sure where to start? Most people do one reset day a week, with a bar a day for the hours in between.
Shop the bundlesHSA/FSA eligible · Secure checkout · free shipping on orders over $199
Every bundle includes
- ✓1-Day Reset Next Gen: organic ready-to-eat soups, crackers, olives, nut bars and teas
- ✓Fasting Bars Variety Pack: chocolate chip, coconut macadamia and nuts and honey
- ✓15% off with a subscription, pause, skip or cancel anytime
Patented formula
Clinically studied
Plant-based
Secure checkout
See Intermittent Fasting Bundles
Starting at $75
Questions
Frequently Asked Questions
The Fasting Bar is clinically shown to have the same effect on your body as water-only fasting in a published clinical trial. Eat one at hour 12 and it extends your fasting, fat-burning state while giving you energy and nourishment, without spiking blood sugar.
On a 16:8 day, a bar at hour 12 carries you through the stretch where most windows break. On a 5:2 or 6:1 pattern, you eat normally five days and use the 1-Day Reset on the others. The Monthly Practice bundle holds four reset days, one for each week of the month.
The Next Gen 1-Day Reset kit brings clinically backed, plant-based organic soups, kale crackers, Italian olives, nutrient-dense nut bars, and teas, portioned across a full 24 hours in a fasting state that supports ketosis, while you are still eating. No prep, no counting, and nothing to decide about what is allowed.
Most people start with one reset day a week and a bar a day for the hours in between. If a weekly rhythm is more than you want, a single reset each month still gives your body a structured fasting day. Start where your week realistically allows.
Yes. Most customers can pay with an HSA or FSA card at checkout. Eligibility depends on your plan administrator, so check your plan if you are unsure.
Shipping is free on orders over $199, and standard rates are calculated at checkout below that. Subscriptions save 15% and can be paused, skipped or cancelled at any time from your account.
Fasting is not right for everyone. If you are pregnant or nursing, under 18, underweight, managing a health condition, or taking prescription medication, speak with your doctor before starting any fasting protocol.
Start this week
Fast better.
Pick how often you want to fast. We'll send the clinically backed nutrition, portioned and ready to eat. Finally, something to reach for at hour 12.
From $75 · HSA/FSA eligible · subscribe and save 15%, pause or cancel anytime
Prolon · L-Nutra. Patented fasting mimicking technology developed with the USC Longevity Institute.
These statements have not been evaluated by the FDA. Not intended to diagnose, treat, cure, or prevent any disease.
Individual results vary. Intermittent fasting is not suitable for everyone. If you are pregnant or nursing, under 18, underweight, managing a health condition or taking prescription medication, consult your doctor before starting any fasting protocol.