Your First 28 Days with Zero: What to Expect

Written and medically reviewed by Nicole Grant, RD

Zero is unlike any other weight-loss and health-gain intervention you’ve tried. No more diets, no more counting calories; just a simple approach to when to eat and when to fast. And with our straightforward, science-backed method, you’ll begin to see transformative changes to your health and well-being in only 28 days.

After 28 Days with Zero…

You can expect to lose 2–5% of your total body weight. A safe rate of weight loss will typically average out to about 1–2 pounds per week, so aim to check on your progress once a week. For consistency, weigh yourself on the same day of each week, ideally first thing in the morning after you use the bathroom. Beyond weight loss, you will also see improved metabolic health and even experience less “tangible” benefits, such as better mood and physical function.

Weight Loss

Healthy weight loss means shedding excess pounds of fat. That’s why intermittent fasting is the cornerstone of your weight-loss journey with Zero. As you extend your fasting time to 12 hours and beyond, you are spending less time burning calories from your previous meal and more time burning fat. Although each person’s fat-burning rates differ based on factors like sex assigned at birth and current practices around nutrition, exercise, sleep, and stress, you can generally expect your innate fat burning to get a boost after 12–16 hours of fasting. This is the average amount of time it takes your body to switch from primarily burning the food you just ate and the carbs stored in your liver to burning fatty acids.

Zero also helps to spontaneously reduce caloric intake. When you fast, you contain your food intake to a predetermined period of time — a.k.a. your eating window — resulting in fewer opportunities to snack or overeat additional calories. Studies have shown that restricting your eating to an 8-hour window can spontaneously produce a calorie deficit of up to 500 kcal per day. This reduction, combined with a boosted fat-burning rate, is what ultimately leads the number on the scale to drop.

Improved Metabolic Health

If “metabolic health” seems vague, let’s get specific. In the context of your first 28 days with Zero, the metabolic health improvements we’re referring to include improved weight, blood sugar, heart health, and autophagy. 

While fasting, your body burns through excess glucose and eventually shifts to a metabolic state that keeps blood sugar low and increases your use of fatty acids for fuel. This leads to lower fasting insulin levels and better insulin sensitivity, resulting in a reduced risk of diabetes and other chronic diseases. 

Daily fasting protocols ranging from 12 to 16 hours of fasting have also been shown to improve markers of cardiovascular health. Fasting favorably shifts cholesterol levels, lowering total cholesterol and LDL-C (the kind that leads to clogged arteries) while increasing HDL-C (the kind that protects against heart disease). Four weeks of intermittent fasting have also been shown to decrease triglyceride levels up to 37% — another marker associated with heart health.

Longer fasts of at least 17 hours have been shown to stimulate autophagy, the cellular cleanup and recycling process. By facilitating the breakdown of outdated or malfunctioning cellular parts, autophagy not only helps cells work better but may also offer protection against various diseases, including cancer and neurodegenerative disorders. Over a month of fasting, this vital daily function has been shown to increase significantly

Subjective Benefits (Non-“Scale” Victories)

While you may have initially downloaded Zero for weight-loss and metabolic-health purposes, 28 days of consistent fasting can lead you to experience a few additional benefits that further enhance your quality of life (and make fasting sustainable!).

Various studies indicate that after only 28 days of fasting, people report feeling more in control, like they have more time in their day, and that they don’t feel like they’re following a diet — all positive associations that can help Zero become a healthy lifestyle that sticks. Furthermore, studies have shown that metrics such as self-reported hunger, satisfaction, and fullness remain constant over the 1-month fasting period, which is a significant benefit of fasting compared to other weight-loss methods.

Finally, fasting might actually help reduce stress. After four weeks of daily 16-hour fasts, study participants showed a significant decrease in the Perceived Stress Scale, indicating that they had more positive thoughts and feelings towards daily stressors in their lives. Less hunger, less stress, more time in the day . . . who wouldn’t want to fast!

Getting Started on Your First 28 Days

If You’re a Beginner

The good news is that even if you’re new to Zero and new to fasting, you’re probably already fasting! Most people fast overnight; unless you are waking up to snack, sleep gives you a natural 7–9-hour fast. Intermittent fasting with Zero simply extends this fast a few more hours in order to enhance your fat-burning capabilities.

The trick is to “start small.” Try moving dinner a little earlier or breakfast a little later (or a little of both!) for the first two weeks, and you’ll soon be nailing 12–13-hour fasts. This fast length gets you closer to, if not into, peak Fat Burning — when your body has fully shifted to prioritizing fat for energy — and tends to naturally align with your circadian rhythm. Fasts of 12 or more hours have also been shown to decrease body weight and improve certain metabolic-health markers such as fasting glucose and lipid profiles. Within your first 28 days with Zero, your number-one priority is to maintain consistent daily fasts, so start with what feels achievable and add an extra hour or two as you see fit. 

If You’re Intermediate

As an intermediate faster, you’re probably logging fasts consistently — which is key! Always make sure you’re nailing consistency before you add time to your fasts.

When you’re ready to level up your fasting practice, start aiming for consistent 14–16-hour fasts. Some days may be a bit shorter or longer, and that’s okay. The goal is to have a daily routine that will lay the foundation for fasting to become a regular part of your lifestyle while getting your metabolism adjusted to regularly prioritizing fat for fuel. (And with fasts lasting 14–16 hours, you’ll be sure to hit peak Fat Burning for at least some length of time with every fast!)

If You’re Advanced

Advanced fasters — who are often already consistent fasters — can lean into daily 16-hour fasts. Aim for this length most, if not all, days of the week. Over time, you might find that these 16-hour fasts feel even better than the shorter ones! 

Once you’re fasting for 16 hours on a regular basis, you can really push your fat-burning capacity by mixing in longer (17–18-hour) fasts on a weekly or monthly cadence. There’s no need to go crazy with longer fasts, because remember: You want to stay consistent above all. Longer fasts can sometimes feel intrusive (sipping water at the dinner table while everyone else eats isn’t much fun), so schedule these fasts strategically so you never have to feel like you’re “forcing it.”

Finally, whether you’re a beginner, intermediate, or advanced faster, join Zero’s 28-Day Fasting Challenge. This Challenge helps you establish accountability, motivation, and consistency with your fasting practice and the habits that bolster it.

Conclusion: Lay Your Fasting Foundations in 28 Days

There’s so much you can accomplish within your first 28 days with Zero — and all without resorting to diets or calorie counting! Instead, Zero offers a simple approach to adjusting when you eat and when you fast. Over the course of these 28 days, you can anticipate a range of benefits, from enhancing your body’s fat-burning capabilities to improving your overall health and well-being. Whether you’re a beginner, intermediate, or advanced faster, forming a consistent fasting habit will pave the way for a healthier, more vibrant you in the months ahead. So, set your intentions, track your progress, and continue your journey towards better health with Zero.

Nicole Grant, RD
Posted in Health & Science

A weekly digest with the latest science and motivation.