Zero (Fasting App) Review

Zero (Fasting App)

Why We Like Them

Zero is a health app, specifically dedicated to the practice of intermittent fasting. Founded with the goal of providing everyone the tools to a longer and more healthy life, Zero is the world’s most popular fasting app that will help you track your weight loss goals and provide you with expert guidance, insights, and accountability. Zero will help you live your best life while practicing the art of intermittent fasting.    


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    Zero App Overview

    Before Kevin Rose, a serial and successful entrepreneur, founded Zero in 2017, he was searching for what most of us search for -- a quick way to lose a few pounds. And after learning about Hugh Jackman’s secret to weight loss, he started to explore the benefits of intermittent fasting (IF). Once he got digging through the data, he became more and more fascinated with the idea, which then led him to create the free app, Zero. 

    According to clinical trials put on by Dr. Valter Longo, Director of the Longevity Institute at the University of Southern California, IF has many benefits, including increased focus, improved sleep, decreased risk of breast cancer, positive effects on systemic inflammation, and can regulate blood glucose levels. 

    Zero (creatively named for the amount of food you eat while fasting) was created as a simple way to track your daily fasting. The app comes with two fasting programs but also has a customizable option that allows you to course out when and for how long you care to fast. Zero tracks your fasting hours and your nighttime meal schedule by using your smartphone’s location services to calculate local sunset time. This is an important feature, as one of the rules of circadian rhythm fasting is trying to eat as close to sunset as possible. For example, if the sun sets at 5 pm and you begin fasting at 6 pm, the app would log one hour of nighttime eating. 

    If you’ve been curious about IF, read on to find out if the Zero app could be helpful for you. 

    Types of Fasting Available on the Zero App

    Circadian Rhythm

    This type of fast goes in 13-hour increments. Starting at sunset and lasting until the morning. Circadian rhythm fasting is based on Dr. Stachin Panda’s research, a scientist, and professor at the Salk Institute in La Jolla, CA. This type of fasting mimics the body’s natural clock. 

    16:8 Intermittent Fast

    This fast is one of the most popular types of fasting, as it has been highly regarded by two of Hollywood’s leading men, Hugh Jackman and Dwayne ‘The Rock’ Johnson. Since you spend 16 hours fasting and only eight waking hours where you’re able to eat, most people either skip breakfast or dinner, depending on their daily habits and lifestyle. 

    18:6 Intermittent Fast

    With a longer fasting period, this fast has been said to help get rid of glycogen and instead use ketones to fuel your body throughout the day. It also helps your body eliminate damaged cells when autophagy (your cells’ defense mechanism against illnesses) kicks into gear. 

    20:4 Intermittent Fast

    As a popular 20 hour fast for more experienced fasters, it is known as OMAD, or one meal a day. People that choose to use this type of fast generally only eat dinner, but be warned that this fast isn’t for the faint of heart and that it is recommended to work your way up to the 20:4, especially if you’re a novice faster. This type of fast is beneficial for weight loss, ketone productions, and has been said to improve mental sharpness overtime. 

    36 Hour Fast 

    Known in the fasting community as the monk’s fast, it generally starts on Sunday evening and lasts until Tuesday morning. As one of the most challenging fasts, it is recommended that you only do this type of fast, one if you’re experienced, and two, only once a week. It is ideal for those wanting to reset their metabolism and has extreme cellular cleansing benefits. 

    Custom Fast

    Create your own, specialized fast that works around your schedule. This type of fast is best for those new to fasting and are unsure which fast will work for them. 


    How Does the Zero App Work?

    You can download the app directly from their website or from the App Store or Google Play. Once you’ve downloaded the app, created an account, and signed in, you will select the type of fast you’d like to try (see above). It’s important to know your limits when selecting your fast. You may want to do some research on each to see which fast will suit your needs and fit into your lifestyle. 

    Zero believes there are four essential tools for mastering the art of fasting and provide each of its users with these free of charge. The tools that Zero knows to be helpful and can be viewed on seperate tabs within the app are:


    The timer tool will help you set your goals, start your time, and motivate you to stay on track. While you’re fasting it shows the percentage of time remaining until your fast is complete and you are able to eat. The timer also shows you how many other people are fasting alongside you, ensuring that you’re not on this journey alone. Zero prides itself on being as supportive as possible, as they know fasting isn’t the easiest or most enjoyable experience on the planet. However, like most things, each fast will become easier over time. 


    The explore tool allows you to do just that; explore. Explore the apps’ content library to learn everything you might want to know about fasting, which is all thoughtfully curated by Zero’s Chief Medical Officer, Dr. Peter Attia. The content library includes helpful videos, audio clips, and articles that will guide you through the benefits of fasting and give you tips and tricks to making the most out of each fast. 


    The statistics tool will chart your progress and map out your fasting journey. You can easily sync it with built-in smartphone apps, Apple Health, and Google Fit. With statistics, you’ll be able to track critical health markers, including your weight, resting heart rate, and sleep patterns. This tool is great for studying how you’ve changed with each fasting practice so that you can tweak certain behaviors moving forward. 


    With the journal tool, you can easily reflect on how you feel or how you felt during each fast. Zero will graph your moods along the way allowing you to track trends and adjust each fast over time. 

    Benefits of Fasting

    There are many studies that have shown fasting as a powerful tool and can benefit not only your body but your brain as well. Some of the science-based benefits of intermittent fasting include:

    • Changing the function of cells, genes, and hormones - When you don’t eat for a while, many things happen in your body. Your insulin levels drop, initiating fat burning, the blood levels of growth hormone can increase, facilitating fat burning and muscle gain, and cellular repair occurs. 

    • Helping you lose weight and belly fat - Yes, you are eating less, however, when you go long periods without eating, your body dips into preserved fat sources to use for energy, boosting your overall metabolic rate. 

    • Lowers your risk of Type 2 diabetes - IF helps lower insulin levels, resulting in a reduction in blood sugar levels, especially in men. 

    • Lowers the risk of heart disease - IF has been shown to lower your blood pressure and cholesterol level.

    • Improves metabolic features important for brain health - IF can increase the growth of new neurons and protect the brain from damage.

    Is the Zero App Credible? 

    The Zero fasting app was created by Kevin Rose, a man that is health-conscious and knows a thing or two about meeting the needs of people’s health goals. He also created apps, Less for those wanting to drink less, and Oak, a mediation app that aids in reducing stress and promoting better sleep. Zero is backed by scientific data and employs experienced people with medical or scientific backgrounds. 

    If you’re unsure of what fasting is all about, Zero has a great resource on their website that will help you learn more about fasting as a practice in a section called Why Fasting? We read through this post and can say fasting can be an effective tool for those wanting to lead a more healthy lifestyle or break eating habits that may be having an adverse effect on their health. 

    How Much Does the Zero App Cost?

    Kevin, the founder of Zero believes that all people should be able to improve their health one way or another and will continue to offer Zero for FREE. However, if you’re extremely dedicated to the fasting lifestyle, it’s worth considering Zero Plus. Zero Plus is essentially a fasting coach that will be with you every step of your fasting journey.

    • Zero Plus - $69.99/year (about $6 a month) and includes:

    • Core Tools (timer, library, stats, journal)

    • Custom plans for personalized fasting

    • Premium content

    • Advanced statistics

    • Fasting zones to see what’s happening in your body

    • Access to Zero’s panel of experts with the feature, ‘Ask Zero’

    What Do We Think of the Zero App? 

    We appreciate that the founder is passionate about leading a healthy lifestyle. That he brought on a dedicated team of fasting experts to help him along the way. The website and app are both easy to use and their blog posts seem to have all the information you need to start on the right foot of your journey. If you’re remotely interested in learning more about fasting, we say why not give it a shot. Explore what the app has to offer, educate yourself on the benefits of fasting, and take fasting for a spin!