Noom: What is the weight loss app and does it work?

Imagine that you could lose weight without going on a diet.

Imagine that you could repair your broken relationship with food, with hunger, with your own skin, and in the process shed those 10 pounds you’ve been wanting to lose. Imagine that you could simply learn how to get in touch with your body — thoughtfully, mindfully — and teach yourself not to crave foods that don’t nourish you. Imagine that you could transcend America’s toxic diet culture, and at the same time, you could also be really, really skinny.

That’s the dream that Noom, a buzzy weight loss app targeted to young people, has been selling for years. “With Noom, every day is ‘No Diet Day,’” it declared on Instagram last May. “And yes, we also help people lose weight,” it added in the caption. Noom’s messaging insists that it teaches users healthy, sustainable habits that leave them feeling happy and satisfied as the pounds melt away.

The no-diet diet angle paid off. In February, the Wall Street Journal reported that Noom was valued at $4.2 billion in May 2021, and late last year it expected its 2021 revenue to total more than $600 million. It was even circling the possibility of an initial public offering for early 2022, with a prospective valuation of $10 billion.

But the Wall Street Journal didn’t think that IPO was going to happen anytime soon. “Noom’s key differentiator — applying psychology to achieve long-term weight loss — has recently backfired,” it explained. Critics say that Noom is just another diet app at best, and a deceptive gateway to disordered eating at worst.

“The idea that there could be a way to lose weight without having all of the psychological and emotional hang-ups around food and diet culture is super appealing,” says Meredith Dietz, the reporter behind the recent Lifehacker article headlined “Fuck Noom.” “But I don’t think Noom actually delivers.”

Virginia Sole-Smith, the journalist behind the fat activist newsletter Burnt Toast and a high-profile critique of Noom in Bustle last October, agrees.

In an interview, Sole-Smith said she was drawn to reporting on Noom in part because of the client base that its “not like regular diets” ad campaign was drawing on. “I was hearing from a lot of people who were doing it who didn’t think of themselves as dieters and wouldn’t want to be doing a diet,” Sole-Smith says. “They were like, ‘Well, it’s helping me rethink some of my habits and unpack some of my issues with food.’ And then a few months later, I would hear from them again being like, ‘Actually, it’s ruining my life.’”

The fight between Noom and its critics is part of a larger cultural war that has begun to play out over the past 10 years over how we should think about food, weight, bodies, and health.

In one corner is the traditional diet culture most American women grew up in, which holds that weight is a crucial indicator of health. Under this system, it’s an article of faith that if you simply exercise a little willpower and expend more calories than you take in, you will lose weight. It is also an article of faith that it’s important for your overall wellness and your personal happiness that you be thin at all costs.

In the other corner are the rising anti-diet and Health at Every Size movements. Citing a mounting pile of research, these groups hold that the correlations between weight and health are not nearly as straightforward as diet culture would have you think. What’s more, they add, most diets do not result in long-term weight loss and can even damage your metabolism in the long run.

“There is no other product that could have a 5 percent efficacy rate and be peddled as hard as diets are peddled,” says Sonya Renée Taylor, founder of the digital media and education company The Body Is Not an Apology, citing a widely quoted study from 1959. (While the 95 percent number has been called into question, other studies do consistently show that the vast majority of diets fail.) “And yet corporations still sell diets and sell the idea of a smaller body as a more valuable body, as an inherently healthier body, as a better body.”

Noom appears to be trying to split the difference between traditional diet culture and the rising anti-diet movement. It positions itself as a program that teaches users to lose weight the smart, healthy way, following the tenets of the body positivity movement while still helping users make their bodies healthier.

Its critics say that beneath the buzzy wellness vocabulary and millennial pink branding, Noom is just another diet app. What makes it different from Weight Watchers, Jenny Craig, and their ilk is that Noom is all dressed up in the rhetoric that activists have been using for decades to try to take down diet apps once and for all.


While Noom celebrates No Diet Day on Instagram, in practice, it works like a classic low-calorie diet. After registering, users are prompted to set a goal weight and to decide how quickly they want to lose weight. Noom will then generate a daily calorie budget that users are expected to follow, and it instructs users to log their food every day to make sure they’re staying on track.

While a stated part of the Noom philosophy is that no foods are off-limits, it does give users a stoplight system to classify their foods. Green foods may be eaten in large quantities, yellow foods are to be eaten in moderation, and red foods are to be limited. Because Noom’s system is based around the idea of caloric density, red foods reportedly include not only classic diet villains like desserts and potato chips and red meat, but also wellness favorites like nut butter and full-fat dairy. Green foods are those that contain a lot of water, like fruits and vegetables. Yellow foods include seitan, lentils, and avocado. (Noom doesn’t make the full lists of color-coded food available publicly, but other sources have compiled more comprehensive lists.)

In addition to the calorie budget and the stoplight system, users get a Noom health coach, a peer support group, and daily lessons on the psychology of eating. The whole package costs $199 for an annual subscription, or $60 by the month.

Some users say Noom is a great experience. Emily Gonzales, a 35-year-old labor and delivery nurse based out of LA, was on Noom from May 2019 to August 2020. She says she lost 190 pounds and succeeded in alleviating her Type 2 diabetes. (Two studies suggest that a very low-calorie diet can improve diabetes control and perhaps reverse Type 2 diabetes in people with obesity, although symptoms may eventually return — and reversal may not be possible for everyone with Type 2 diabetes. Per the CDC, a healthy rate of weight loss is one to two pounds per week.)

“I’ve tried everything, on and off, my whole life,” Gonzales said over Zoom. “I’ve done Nutrisystem. I’ve done Medifast, which is like five shakes a day and one real meal. I tried low carb. I tried starving myself.”

Gonzales says she always lost weight on the diets she tried before, but as soon as they were over she would go back to her normal eating habits and gain the weight right back. She could never figure out why certain foods were supposed to be good and other foods were supposed to be bad on any particular diet, so she could never stick with the habits she made there.

Noom, she says, is different: “They teach you the why.” She knows which foods are dense in calories and which are high in water, and she says that eating less calorie-dense foods keeps her fuller for longer.

“I’m never hungry,” she says. “I eat tons of veggies, tons of fruit.” Gonzales is currently on a diet of 1,400 to 1,800 calories a day and plans to continue on it, although she no longer tracks her calories daily. (Health professionals recommend women eat around 2,000 calories per day, although this number is highly variable depending on levels of physical activity, metabolism, age, height, and more.)

Other Noomers didn’t have such a good time. Sara Davis, a 40-year-old marketing and communications writer in Philadelphia, says she turned to Noom in 2018 for help managing her chronic illness.

“I had read a lot of fat acceptance blogs, so I knew that diets didn’t work,” Davis says. She has Hashimoto’s thyroiditis, an autoimmune disorder that can include weight gain among its symptoms, and she had been gaining weight steadily for years.

“It obviously negatively impacted my life in many ways,” Davis says. “I experienced body dysmorphia. I had to buy new clothes every year. I was seeking out ways to manage my weight that didn’t seem to be diets.”

For a while, Davis went to a nutritionist, who taught her to keep a food journal and watch her calories in and her calories out. Then she switched jobs and found that her new insurance wouldn’t cover the treatment. Noom presented itself as an affordable solution: a way to lose weight that wasn’t really a diet.

Once she signed up for a free two-week Noom trial, Davis found herself disappointed. She was already tracking her daily exercise and food intake in a series of detailed charts and graphs. She already had a basic understanding of nutrition, so Noom’s daily tips and calorie-tracking systems weren’t doing much for her. “It talked to me like I was very stupid,” she says.

The one big change Noom did offer Davis was that it cut her daily calories, by a lot. She was already eating a fairly small daily allowance of 1,500 calories, but Noom brought her down to a 1,200-calorie diet. That’s what nutritionists consider the bare minimum required for most women to sustain daily living. Some of them call it a starvation diet. (Noom announced last November that it would no longer recommend 1,200-calorie diets and raised the level by 10 percent, setting a new minimum recommendation of 1,320 calories for women.)

“As a person with Hashimoto’s thyroiditis, I always struggle with energy and mood and just being tired all the time,” Davis says. “But on 1,200 calories I was very tired. I could not think. Very achy. And then it made me mean. I was so irritable. I was snapping at people. I was impatient. I had kept having to apologize for things that I said. I was not myself during that period.”

Davis decided to cancel her Noom membership before the free trial was over. She found, though, that Noom had gotten into her head: She kept counting calories and she kept trying to restrict them as much as possible.

After a few months, she decided she wanted more structure in her weight loss efforts. She applied to enter a weight loss study at the university where she worked.

There was just one problem. To enter the study, you had to go through a psychological screening first. Once Davis had been screened, she was told she couldn’t join the study. Instead, she was given a reference to a disordered eating clinic.

“So that was for me a wake-up call,” Davis says. “I was doing things that are considered normal by some — by Noom, by the general culture. But they’re actually not. They’re maladaptive behaviors. They’re disordered behaviors.”

Now every time Davis sees a Noom ad, she says, she reports them as a scam.

Davis and Gonzales had extreme experiences with Noom. A lot of people go through Noom without either curing their chronic illness or getting a diagnosis of disordered eating. Instead, many people have the same experience almost everyone has on a diet: They lose some weight, stop the diet, and then gain it back.

Yves Grant is a 50-year-old technical writer who joined Noom in 2019 after seeing a Facebook ad. “I was the type of person that never had to watch my weight because I had a high metabolism or whatnot; I could eat whatever I wanted,” he says. “But at that time I was getting older and getting heavier.” He liked that Noom advertised itself as offering community support, and that it told him it wouldn’t be a diet but a lifestyle change.

In practice, Grant says, Noom didn’t quite live up to his expectations. He thought he’d get more personal attention and concrete tips from his health coach, who he says mostly offered reflective questions. While the daily psychological tips were useful, they rapidly got overwhelming.

But the food tracking and calorie restriction, he says, really were useful. Between May and August 2019, he lost 30 pounds, and he says he grew to enjoy the feeling of hunger.

After that initial drop, Grant’s weight loss plateaued. Around April 2020, he lost interest in Noom and stopped logging in, and he never renewed his membership. Now, he says he’s gained back half the weight he lost, in part because he found the diet unsustainable. “Never eating potato chips, never?” he says. At one point on Noom, he began keeping a list of all the foods that he loved and felt he could no longer have.

Still, Grant doesn’t blame Noom for his regained weight so much as he blames his own bad habits. If he wants to lose weight again, he says, he knows what he has to do.

“They work for me!” he says. “I’d love to see them succeed.”


The anti-diet movement has been around since at least the 1960s, but only more recently has it begun to acquire cultural cachet, due in large part to social media. It has many branches: anti-diet, fat acceptance, body positivity, body neutrality. It’s been pushed forward by dozens of journalists and food professionals and bloggers and authors. In recent years, nutritionist Christy Harrison’s book Anti-Diet helped mainstream the concept of intuitive eating, while the popular podcast Maintenance Phase from journalists Michael Hobbes and Aubrey Gordon has been debunking the junk science behind diets.

At the center of the anti-diet movement are two scientific claims. The first is that the relationship between weight and overall health is unclear, and that it’s possible to be both a healthy fat person and an unhealthy thin person. The second is that most of the time, dieters end up gaining back all the weight they lost and then some within five years of the initial diet. So even if it were clear that being thin is important for health, that information wouldn’t do much for most fat people.

The data on the first claim shows it to be mostly true, with caveats. A 2014 meta-analysis in the scientific journal World Obesity found that between 6 percent and 75 percent of those classified as obese were “metabolically healthy,” depending on the definition used for “metabolic health.” Another meta-analysis, this one in the Journal of the American Medical Association in 2013, found that while those with a Body Mass Index (BMI) of 35 and above had a higher mortality rate than those with a BMI considered normal, lower grades of obesity were not associated with a higher mortality rate, and those who were moderately overweight had a significantly lower mortality rate. (Per the Centers for Disease Control and Prevention, a BMI of 18.5 to 25 is considered normal, and 30 and above is considered obese.) Finally, a third meta-analysis in 2014 found that overweight and obese people who were fit had similar mortality risks as normal-weight people who exercised, while people who didn’t exercise had twice the mortality rate, regardless of BMI.

All of these studies may be impacted by fatphobia, which, as Sole-Smith wrote in Scientific American in 2021, “shows up in the questions that researchers don’t ask” — questions like what other risk factors might disproportionately affect fat people, such as poverty, smoking, or the unhealthy effects of yo-yo dieting. Fatphobia even affects the way we measure obesity. While our medical system is built on the idea of the Body Mass Index as an effective measure of obesity, the BMI was originally designed to study populations, not individuals, and was based entirely on the average height and weight of white European men. The CDC and National Institutes of Health adopted their current BMI standards for obesity in 1998, on the advice of a private organization whose top donors were pharmaceutical companies making diet pills.

The data on the second claim is much more straightforward. Studies consistently show that it is very, very rare for dieters both to lose weight and to maintain their weight loss. One 2015 study published in the American Journal of Public Health found that for people classified as obese, the probability of attaining a BMI-normal weight is 1 in 210 for men and 1 in 124 for women. For people classified as morbidly obese, the probability goes down to 1 in 1,290 for men and 1 in 677 for women. Another 2015 study in World Obesity found that nearly all dieters gain back the weight they lose within five years, and one-third regain more than they lost.

While the science around weight is murkier than anyone would like to admit, there seems to be a fairly clear reason why dieters tend to regain their weight so consistently: Human bodies don’t like scarcity. If you restrict your calories, after an initial period of losing weight, studies suggest that your metabolism will slow. It will become easier, not harder, for you to put on weight. And your body will crave more calories, with more and more strength, until you break your diet and, often, find yourself binge-eating uncontrollably.

So why, anti-dieters want to know, do we bother dieting at all? Why have we allowed an entire industry to rise up around telling people to do this impossible thing, especially if it’s not clear that it’s even medically necessary? What do we get out of dieting except alienation from our bodies, a deeply disordered relationship to food, and a dysfunctional metabolism?

In fact, anti-dieters argue, dieting can damage the very bodies it promises to heal. In addition to slowing the metabolism, frequent dieting is associated with higher mortality rates and can double the risk of death by heart disease in patients with coronary artery disease. It can also damage the mind. One study finds frequent dieting is associated with high rates of depression. Dieters can become overwhelmingly fixated on food. In the Minnesota Starvation Study of 1944, 36 male volunteers were kept in a state of semi-starvation for six months on a 1,570-calorie-a-day diet. Before long, they became obsessed with food, fantasizing about it and discussing it at all hours. Now doctors consider extreme preoccupation with food a symptom of starvation, in part because of this study.

Moreover, the boundaries between dieting and eating disorders can easily become porous. Anti-diet books like Intuitive Eating are pitched to dieters who have found themselves estranged from their body’s hunger and satiation signals and need to relearn how to eat. Meanwhile, in the pro-ana forums and hashtags where self-identified anorexics enable one another, posters brag about teaching themselves to enjoy the feeling of hunger.


In 2016, a woman who we’ll call Amy finished her graduate degree in nutrition and her dietetic internship, making her a board-certified dietician. It wasn’t an easy journey for her. “It’s not uncommon for many people in the nutrition field to get there by way of their own disordered relationships with food, and I’m definitely in that camp,” she says.

Amy’s plan was to help other people take control of their relationships with food, in the way she craved taking control of her own. They would all learn to eat less and more healthfully, to keep their bodies slim. As she kept exploring nutrition after graduating, Amy began to encounter new ways of thinking about food.

First, she learned about mindful eating, the practice of paying close attention to the food you eat and your body’s response to it. From there she learned of intuitive eating, the practice of rejecting all food rules and allowing your body to guide your eating. Then she began hearing about Health at Every Size, the movement that argues that it’s possible to live a healthy life no matter what your weight is.

“I started reading the research from that lens, rather than my very much weight-biased lens,” Amy says. “Everything started to line up and I was like, ‘Oh my gosh, this makes so much sense.’ It really turned my world upside down.”

Amy was fascinated enough by what she learned about intuitive eating and body positivity to want to incorporate both into her growing practice as a nutritionist. She wanted more experience using both of them under someone else’s supervision before she was ready to go into private practice. When she heard about a promising weight loss company that seemed to be using a lot of the rhetoric of intuitive eating, she jumped at the chance to interview for a job there.

In March 2018, Amy began working as a health coach for Noom. “I was optimistic that there would be opportunities to use intuitive eating, especially since they incorporate it in their curriculum,” she says. Now, she says, “I think I was probably lying to myself.”

(Amy asked not to be identified by her real name due to a nondisclosure agreement she signed with Noom. Vox has verified her employment with the company.)

As Amy put in her time at Noom, she found herself gradually losing faith in the company.

The health coaches, she says, were perennially understaffed. While the company’s goal was to have each coach working with 300 users a week, at peak season, Amy says she found herself handling 800 active users a week. In an emailed statement, Noom said, “We don’t publicly break out the ratio of Noom Coaches to users, but caseloads are closely monitored to ensure that all users are receiving the support they need to reach their goals.”

Amy says the staff received a cash bonus for the extra work, and she thought all her colleagues were supportive and well-intentioned. She was worried, though, about the users she was supposed to be coaching.

“They were starting to see that they’d lost some weight but now they were gaining some back,” she says. “They were having a lot of difficulties. They were having a lot of food preoccupation. They were having all these really classic signs of starvation.”

Amy tried to work closely with the cases she was assigned to. She would tell them that the calorie budget they had been assigned was a minimum, not a maximum, to try to keep people from starving themselves. Still, she found herself fighting against the design of the app, which flared bright red warning signs whenever users went over their calorie budgets. The high workload also meant she never had time to pack all the nuance into her conversations with users that she wanted to.

In September 2018, HuffPost published a feature story from future Maintenance Phase co-host Michael Hobbes titled “Everything You Know About Obesity Is Wrong.” It was widely read and widely shared across the internet, including inside of Noom.

“That was one of the biggest articles that had come out in the mainstream [news] since I had been aware of the [size-]inclusive paradigm, so that was really exciting for me to see it getting that kind of coverage,” Amy says. However, “the response to it at Noom was not satisfying to me.”

In his article, Hobbes argues that our culture’s overwhelming focus on shaming fat people into losing weight is cruel, unproductive, and anti-scientific. “It’s time for a paradigm shift,” Hobbes wrote. “We’re not going to become a skinnier country. But we still have a chance to become a healthier one.”

Amy says that she had a productive conversation about the article with her supervisor, and that she saw plenty of her colleagues discussing it in good faith. “People were starting to question some of the things that overall Noom was perpetuating,” she says.

Ultimately, though, Amy felt that Noom’s response to the article was dismissive. That, she says, is when she knew she couldn’t stay at Noom.

“It really just started grating on me, the whole curriculum they have, the way they explain it. Hearing their ads on NPR basically any time I turned the radio on,” she says. “It just got really frustrating to hear the message over and over again that ‘we’re not a diet’ when they very clearly are.”

Shortly after the HuffPost article came out, Amy transitioned from full-time to part-time. Six months later, she had enough money to leave for good and focus on developing her private practice as an anti-diet dietician.

Meanwhile, Noom was flourishing with the onset of the pandemic. Stressed stay-at-home workers began obsessing over whether they were putting on the “Covid 15,” and Noom was ready and waiting for them.

As Noom kept scaling up, the backlash was building. In January, Alina Stone tweeted, “every noom ad is like ‘we’re NOT a diet. we’re an eating disorder :).’” The joke was enough to get Noom trending worldwide, with former Noomers sharing their stories in the replies. (In an emailed statement to Vox, Noom director of communications Sara Cohen said, “We take eating disorders extremely seriously and have since the earliest days of building our product.”)

“I was just kind of tired of hearing the ads and tired of them pretending they were not a diet,” Stone says in a Zoom interview. “It was constant, in podcasts and on YouTube. And it’s really hard to skip the ads on YouTube! They can use these buzzwords and catchphrases all they want, but it’s a diet.”

For ex-Noomers, the anti-diet nutrition principles that the company claimed to teach aren’t quite neutral territory anymore. In her private practice, Amy says she regularly sees clients who went through Noom’s program. When she tries to introduce intuitive eating concepts to them, she finds that she tends to have problems.

“It takes a lot of work to go through these lessons again,” she says. “They’re like, ‘Oh, yeah, I understand that.’ And then when they’re talking, it’s kind of like, ‘I’m hearing that you don’t [understand it],’ because of the way that Noom has discussed some of these topics. It’s really keeping people in this disordered relationship with food.”

Sonya Renée Taylor, the founder of The Body Is Not an Apology, says she wasn’t surprised to see Noom present itself with co-opted anti-diet language. “I expect capitalism to capitalize,” she says. That doesn’t mean, she adds, that Noom isn’t hurting people.

“At the end of the day, any modality that tells you that somehow you’re wrong, that your natural body cues are failing you, and that somehow you’re going to opt into a better life by being some other kind of body can’t do anything but fuel oppression,” Taylor says. “And anything that fuels oppression is inherently, innately harmful.”