ReSet by ProLon

The only Intermittent fasting bar scientifically formulated to allow you to fast with food™!
Regular price $44.99 Sale price$24.99 Save 44%

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*If you have diabetes or are taking any medication that affects blood sugar please consult with a healthcare provider prior to attempting fasting or a low-calorie diet. 

*Consult with a healthcare professional before starting any diet, supplement, or exercise program. 

Interested in ProLon 5-Day Fasting Nutrition Program? Click Here ➝

Conquer your intermittent fasting goals
Skip hunger, boost energy so you can fast for longer!

Plant-based protein - Non-GMO, Gluten Free

Incorporate Fast Bar into your fasting window

Experience the smart way to intermittent fast. incredible combo of premium nuts, like almonds, pecans, and macadamias. Curb your hunger, nourish yourself, and get the most out of your day.

What they love!


“Tastes great and keeps me going until it’s time to break my fast.”

 Michelle Yabko
Los Angeles, CA

Delicious and very filling. I can have a bar at 8:30 AM and I am not hungry until noon, great job!

United States

I love these bars. The texture is on point. They present as homemade and are delicious! You guys got it right! Worth every penny!

Dana Funicelli

Bars are tasty and satisfying. I have a bar each morning and my hunger is abated until I begin eating at noon. They are exactly what I was looking for.

Anthony Tamel
United States
Yes, we're fasting with food™

Intermittent Fasting is already the #1 diet because of the benefits, both inside and out, and how seamlessly it can fit into your daily life. But it’s our groundbreaking innovation - fasting with food - that’s truly changing the game.

Hack your fast and enjoy the benefits without starving.

View The Study

Designed For Fasting

Fast Bar is a nutritious blend of premium ingredients, designed to support intermittent fasting programs. Eating Fast Bar curbs your hunger and gives you the fuel you need to make it to your next mealtime.

Fasting With Food

Backed by Science

After 20 years of research, scientists discovered a nutritechnology that nourished the body while keeping it in a fasting mode known as the Fasting Mimicking Diet (FMD)® which includes the nut-based Fast Bar.*

Science of Fasting

Premium Formulation

The premium ingredients that make up Fast Bar support fasting goals through a micro- and macro-nutrient profile of more beneficial fats to fewer carbohydrates and less protein. *See nutrition information for fat content

Go ahead, Ask Away

Eat Fast Bar in the morning to help extend your fast* or as a snack anytime during the day to help curb your hunger.

Many use it as their secret late night snack or morning breakfast, since it keeps your glucose and ketones equal to drinking water alone!

Fast Bar® is an intermittent fasting bar that can help curb your hunger without breaking your fast, so you can fast for longer. It has been clinically shown to keep your body in a fasting state even after eating. You can eat it in the morning after your overnight fast to help curb your hunger and extend your fast until your next meal.  A clinical trial showed that eating a Fast Bar after an overnight fast has a similar impact on ketones and a nearly identical impact on blood glucose as drinking water*.

* Benefits seen in a randomized, controlled study in 105 adults after a 15-hour overnight fast comparing the glucose and ketone results every hour for 4 hours in the Fast Bar group, breakfast group and water-fast group. Click here to read the published scientific article.

You should eat Fast Bar once a day, as we want people to follow a healthy, balanced diet including regular meals during the day. 

You can eat it in the morning after your overnight fast or as a healthy snack anytime during the day, in addition to meals, to help curb your hunger.

The impact and safety of consuming more than one Fast Bar per day hasn’t been studied, and we recommend that you eat only one Fast Bar in the morning or evening, along with a healthy, balanced diet for your other meals. 

Fast Bar is great for supporting Time Restricted Eating and other short fasts.  If you seek the benefits of Prolonged Periodic Fasting, our 5-Day ProLon Fasting Mimicking Diet (FMD) has been extensively tested, has been safely used by hundreds of thousands of generally healthy consumers, and has been clinically tested to provide many benefits, and support overall metabolic health when used in multiple consecutive cycles. For more info on ProLon, go to

The Fast Bar study tested the effects of eating a Fast Bar at breakfast time (after a 15-hour overnight fast), compared to either skipping breakfast or eating a standardized breakfast bar. The study looked at blood glucose and ketone levels over the 4-hour period after breakfast time and showed that blood glucose levels in patients eating Fast Bar were nearly identical to blood glucose levels in patients who skipped breakfast.

Ketone levels over the 4 hours were also very similar in both groups. These results showed that eating a Fast Bar doesn’t interfere with key physiological markers of fasting.  The study also showed that Fast Bar gave people a feeling of being fuller and curbed the desire to eat for up to 3 hours after consumption. In other words, you can eat a Fast Bar to help make fasting easier and more pleasant, and maintain similar ketone and blood glucose levels as a water-only fast.

Fast Bar’s ratio of fats to carbohydrates + protein = 1.4:1. That’s 1.4 grams of fat for every 1 combined gram of carbs and protein, which fits nicely into a modified Keto diet. 

In our studies, ketones were measured over the 4-hour period following consumption of a Fast Bar, and the level of ketones were no different than those in participants who continued an overnight fast with an additional 4 hours of water-only fasting and no Fast Bar.

According to the colloquial definition, ‘fasting’ means ‘not eating’.  However, it’s important to consider what actually happens inside you during fasting that makes it different than eating. Your body notices food through nutrient-sensing pathways, and when you don’t eat, these same pathways tell your body that you’re in a fasting state.  This is what triggers fasting at a cellular level, and it’s what we mean when we talk about mimicking a fast – it’s possible to trick these sensors into thinking you’re in a fast while still providing the body with nourishment.  This is the science behind the Fasting Mimicking Diet and Fast Bar. This is the nutritional breakthrough which enables consumption of specific foods while still maintaining a fasting state.

Your body fuels itself while fasting by tapping into its internal energy reserves including fat stores and stored energy in your liver and other organs. This one of the reasons why there’s weight loss and fat loss when fasting. Fast Bars are low in sugar and protein, and are designed so that their energy is released slowly in the body. This allows your cells to keep the nutrient sensing pathways in the ‘fasting’ state and draw on fat from the diet and from your body’s fat stores for energy. 

For those of you who are into biohacking, think of Fast Bar as the ultimate bio-hack – fueling your body so that you don’t get hangry and your cells get nourishment, while staying in a fasting state!