Written and medically reviewed by Naomi Parrella, MD
It’s a new year! And for many people, that brings renewed motivation to improve their health, often starting with weight loss.
As a physician who practices obesity and lifestyle medicine, I see this in both my clinical work and in my work with organizations and digital health platforms. People are using a range of tools, from intermittent fasting to calorie reduction, GLP-1 medications, or even thoughtful combinations of these approaches. They all work slightly differently, but the goal is the same: to lose fat. However, across these approaches, I’ve noticed protein intake often drops along with calories. The result of this unintended consequence is a real risk of losing muscle while losing weight.
That insight is what inspired our team at Zero to build a more thoughtful solution: the Protein Score.
Why Muscle Loss Can Happen When You’re Trying to Lose Weight
First, let’s talk about why you lose muscle. Your body is in a constant state of breaking down and rebuilding muscle tissue. This is normal routine repair. When you’re eating enough protein, your body replaces the damaged tissues with new ones.
However, if you don’t get enough protein (whether due to less food or less time to eat), your body can’t keep up with the rebuilding process. That leads to muscle loss, which can make you physically weaker, weaken your immune system, and even slow your metabolism. It prevents your body from being able to thrive.
What Is “Enough” Protein?
The solution to the risk of muscle loss sounds simple — just eat enough protein. But what is enough?
The answer is that it varies. The U.S. Recommended Dietary Allowance (RDA) for protein just increased to approximately 0.5–0.7 grams per pound of body weight per day. That’s a big step up from the minimum 0.36 grams per pound of body weight recommended in the past! But if you’re fasting or losing weight, that “average” protein recommendation likely isn’t enough.
My peers and I recommend 0.7–1.0 grams per pound of body weight per day for most adults, especially those who are fasting, aging, active, or intentionally losing weight. This calculation, of course, changes constantly — for instance, as individuals on a weight loss journey start seeing progress, their body weight changes, so the calculation needs to be updated. This leads to a lot of math, and also a lot of discussion about how to meet their protein needs without overdoing the rest of the macros (and calories).
That’s where the new Protein Score comes in.
Protein Score
Zero’s Protein Score is a single, personalized metric that tells you exactly how you’re doing with protein consumption. It’s not just counting how many grams of protein you’ve eaten (although that’s front and center in the app, too). Instead, it’s calculating the percentage of calories you’ve eaten that come from protein. If you eat Greek yogurt and a protein bar, for example, your score will be higher than if you eat a bagel with jam and butter.
As I frequently share with my patients, the purpose isn’t to label foods “good” or “bad.” The goal is to learn how to choose foods that will help you meet your body’s protein needs without raising insulin or adding to fat mass. That’s exactly what the Protein Score is teaching you, and why I’m so excited about this new feature in Zero Plus.
The bottom line is that you can thrive and lose weight. You just want to be intentional about your protein consumption. It’s been proven in research and in the clinics: tracking increases success. Tracking your protein will help guide you to the amount your body needs to perform its best. So why not start today?
This information is for educational purposes only and is not medical advice. Please consult your healthcare provider for individualized care.
If this topic resonates, I invite you to learn more about tracking protein, hydration, and other healthy habits in the new Zero Plus. Understanding your biology, and working with it, is one of the most powerful investments you can make in your health.
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