What is Noom?

The weight-loss program claims to take a psychology-based approach. What does that mean exactly and, more importantly, does it work?
Published August 29, 2022 | Updated July 3, 2024
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Noom says it’s a lot of things. It’s a behavior change program. It’s backed by doctors, psychologists, nutritionists, and personal trainers. But the true lure seems to lie in what it says it’s not: A diet.

And yet, with a stoplight system for identifying food choices, calorie targets, and a focus on daily weigh-ins, Noom primarily does function as a diet. Read on to learn how Noom works, its pros and cons, how it differs from other weight-loss programs (like ours), and more—so you can make the best call for your wellness goals.

What exactly is Noom?

Noom’s Healthy Weight program is a 16-week starter program that claims to rely on behavioral and lifestyle intervention to help you understand your eating habits, improve your relationship with food, and lose weight.

Though Noom is not a traditional diet in that it does not provide specific guidelines on what to eat, it does utilize a red-yellow-green, color-coded stoplight system to help you choose foods that are more or less calorically dense. This system is also designed to push you toward the proper portion sizes. For instance, you can generally eat more spinach (green) than brownies (red). Another way to look at it is that a green light means you can increase portion sizes—don’t hesitate to toss more roasted veggies onto your plate—while a red light suggests that you shrink your portion size, if you choose to eat it. That might mean using a small amount of olive oil (red) to roast those veggies in, or taking a small cut of beef filet (also red). Ultimately, this helps you make choices about what and how much to eat in order to stay within your calorie budget.

As for that calorie budget, despite the fact that the program attempts to separate itself from traditional diets, calorie counting is a big central focus on the Noom plan. After taking a 10-minute personalized quiz, Noom gives you a caloric target that you can adjust up or down within the app by changing the speed at which you’re aiming to lose weight.

In addition, there are self-directed lessons that you are encouraged to listen to and work on. The Noom weight curriculum asks you to complete 10 mini courses that help you set a variety of habits in motion, like goal setting, relieving stress, practicing gratitude, or learning the 10 types of hunger. Noom calls these bite-sized lessons in psychology and behavioral science.

What can you eat on Noom?

At the heart of Noom is the stoplight categorization, designed to help you figure out what to eat and what to avoid. Its appeal is that it’s easy to understand, even if this is the first time you’re learning about a healthy diet. If we told you that cookies are a “red” food—you’d likely interpret that to mean “stop”—and you might avoid eating it altogether. Here is a sampling of foods within each of the colors in Noom’s color system.

Green Foods

Vegetables, fruit, whole grains, and some lean proteins make up this color category. These foods are low in calories and also tend to be higher in nutrients. You may think that “green” means “keep going,” as in eat as much of these foods as you’d like. But with Noom you cannot eat unlimited amounts of most of these foods, since you still have a calorie budget to adhere to. For example, eating unlimited amounts of brown rice with Noom could cause you to blow your daily calorie allotment.

  • Spinach
  • Broccoli
  • Bell peppers
  • Cucumbers
  • Tomatoes
  • Apples
  • Bananas
  • Strawberries
  • Tofu
  • Non-fat yogurt and cheese
  • Skim milk
  • Unsweetened almond milk
  • Oatmeal
  • Brown rice
  • Whole- grain bread
  • Quinoa
  • Tuna (canned in water)

Yellow Foods

These are lean meats and starches, and should be eaten in moderation. These foods are nutritious, but do have more calories compared to foods in the green category (see below). You’re encouraged to watch your portion sizes of foods within the yellow category.

  • Grilled chicken
  • Turkey breast
  • Salmon
  • Lean ground beef
  • Eggs
  • Low-fat yogurt and cheese
  • Black beans
  • Chickpeas
  • Avocado
  • Whole-grain tortilla

Red Foods

Foods considered “red” are those that are the most calorically dense, such as oils or nuts. Those, like desserts, may also be less nutritious.

  • Oils
  • Seeds
  • Nuts and nut butter
  • Raisins
  • Red meat
  • Dessert

Advantages of the Noom diet

There’s a lot of buzz surrounding Noom. Since its launch in 2008, the brand claims that over 45 million people have downloaded the weight-loss program’s app. Among the touted benefits of the plan:

It’s accessible

Noom is an app-based program, which means that you get to carry it (and the support contained within it) wherever you go. “I think that many people like having a program at their fingertips and being able to access it whenever they have a chance,” says Laura M. Ali, M.S., RDN, a registered dietitian nutritionist, and a culinary nutritionist based in Pittsburgh, Pennsylvania. “You can listen to motivational tips on-the-go and the lessons when you have time,” says Ali.

WeightWatchers® offers the same convenience—you can follow the program solely using the weight-loss app, but you can also attend virtual or in-person Workshops led by expert coaches.

Customized to you

Before starting the program, you’re asked 65 to 70 questions about your health and some behaviors, says Ali. And that makes it feel “tailored to you and your needs, which I think is very attractive for people,” says Ali.

That’s one of the reasons personalization is a cornerstone of WeightWatchers. After you sign up, you’ll answer 12 questions so we can get to know you better — including sharing your dietary preferences and your “why” for weight loss. From this, a program is created specifically for you.

Helps with goal setting

If you’re looking to lose a certain amount of weight in a specific time frame, the app’s food, exercise, steps, and weight-tracking tools help you keep tabs on your progress. Noom also encourages the use of SMART goal setting, where each goal is specific, measurable, attainable, relevant, and time-based. (This goal-setting approach could also backfire, though—more on that in a minute.)

Goals are also part of WeightWatchers, but with a focus on reaching them and sustaining them. Your personal goal might be to lose a certain amount of weight in a certain amount of time, but WW will never adjust your individual program to speed things along—because research (and life experience) tells us that sort of weight loss isn’t as long-lasting.

Focuses on behavior change

It’s not always about what you’re eating or even how much, but why you’re eating. For example, you’ll learn about a “behavior chain,” or what triggers and thoughts cause you to act in a certain way. Maybe you ate a burger at lunch, so you immediately assume you’ve exceeded your calorie budget that day, and because you weren’t perfect, you decide to stop at a drive-through to pick up dinner since you already “blew it.” If you stop and analyze your own triggers and thoughts, you can then stop the chain of events that cause you to overeat less-nutritious foods.

Behavior-change strategies are baked into virtually every part of the WeightWatchers experience. The WW Science Team—comprised of psychologists, registered dietitians, behavioral scientists, and other experts—is equipped with decades upon decades of research on what helps and what hinders weight loss. And they use all that intel to build techniques that help members avoid and overcome hurdles (including the all-or-nothing thinking that can lead to a drive-through free-for-all).

Downsides of the Noom diet

Like any diet, there are things that users find lacking with Noom. Here’s what to consider before going on the program:

The cost can be steep

You will be offered a weeklong choose-your-price trial ($0.50, $3, $10, or $18.37). After that, you enroll in a time-based plan. The most popular option, according to Noom, is $159 for 4 months, which you pay upfront. WeightWatchers, however, provides individualized digital plans that start at $22.95 per month.

Noom is run through an app only

While there are certainly perks to an app-based program, including the fact that it can follow you anywhere, some people thrive on in-person social support. It’s up to you to decide what you need, says Ali. You may do just fine with check-ins with your coach through the Noom app, or you may want more of the social connection that virtual or face-to-face regular meetings provide. Some criticisms of Noom coaching is that it’s not very personalized and each coach has many users to juggle (in April 2022, Noom laid off 495 of their wellness coaches), so you may not feel as if you’re getting the individualized support you need.

Community support is a top priority with WeightWatchers. In addition to a robust members-only social platform filled with people working toward goals and cheering each other on (Connect hosts an average of 9,000 posts a day), there are thousands of in-person and Virtual Workshops with an expert coach to choose from. The Workshops happen around the clock, and members can attend as many of them as they’d like without having to book in advance.

Requires a time commitment

Changing up your approach and relationship with food certainly takes time, and that can be a plus or a minus, depending on what you’re looking for. “Noom may be a bit labor-intensive for some people. Listening to lessons, motivational tips, and having to log everything you eat may be cumbersome,” says Ali. It’s all about knowing what support and structure you feel you personally need to succeed.

With individualized food plans, easy-to-use trackers, a barcode scanner, fun workouts, more than 11,000 recipes, and coach chat available 24/7, WeightWatchers tools and features make reaching a goal fit into members’ unique schedules.

Focuses on calorie deficit over nutrition

Some users find the calorie goal that they’re given to be extremely low, which may feel restrictive and difficult to stick with. It’s important that calorie goals are individualized and based on the gender you identify with, as well as other factors like your height, weight, activity level, and weight-loss or health goals, says Ali. “I’m not a fan of setting generic calorie goals. Every person is unique and has different needs,” she says.

Focusing on a calories-in, calories-out ignores the fact that some higher calorie foods provide optimal nutrition to support your goals and help you feel satiated. One of the biggest criticisms of Noom is that it is so calorie-oriented and focused on the stoplight system that people are apt to fill their diet with green foods only, missing critical nutrition that consuming a variety of foods (including the yellow and red foods on their list) offers. For example, your body still benefits from the muscle-building power of protein found in eggs or fish, and the heart-healthy fats found in olive oil—even if they’re not listed as “green.”

No food is off limits with WeightWatchers. So, while you have your own individualized Points Budget, there are more than 200 ZeroPoint™ foods and you eat what you want. What’s important is that you track how much you eat, move, and other healthy habits. Science proves that being mindful of healthy choices helps you reach and maintain your goals.

Does the Noom diet work for weight loss?

When you go onto Noom’s site, you’ll see reviews and a lot of data suggesting that its methods are successful for most people. If you are looking to lose weight and diets have failed you before, it’s completely understandable that Noom’s non-diet messaging would be attractive. But the program is not a slam dunk for everyone.

One study in Scientific Reports that included nearly 36,000 participants using Noom, found that 78% lost weight over about a nine-month period. Just 23% of those lost more than 10% of their body weight, while one-third lost less than 5% of their total body weight. The fine print here—or something easily glossed over—is that the research authors only used data for people who used Noom two or more times per month for just six consecutive months.

A more recent study in Health Education & Behavior of about 7,500 male Noom users found similar results. Overall, while many people do hit the 5% mark—the amount of weight loss considered to be “clinically meaningful” and that’s associated with better blood pressure, cholesterol, and blood sugar—the average user does not. A 2021 study found that by 16 weeks, people lose an average of about 3% of their body weight. All in all, Noom is supported by a small body of research, with 30 peer-reviewed studies.

In contrast, WW has a well-established track record for weight loss and improving health behaviors, including decades of research. Over 175 studies have been published on WeightWatchers, including more than 43 publications using gold-standard randomized controlled trials to examine the efficacy and impact of the WeightWatchers program. (There’s even a global success registry with over 13,000 members who’ve sustained meaningful weight loss.)

The bottom line

Noom is a popular program and it can be a safe way to lose weight, as long as you remain committed to following the steps—but, most of all, it produces weight loss by encouraging calorie deficit rather than through psychology or behavioral change.