Tracking food intake to lose weight is an age-old idea with a modern twist. Numerous smartphone apps, many with free features, can help users tally up exactly what has been gobbled down.

And now, a new study finds that those who track consistently do lose more weight than the less conscientious trackers. The surprise? Even those who tracked less than daily lost weight.

While food tracking draws praise from some, it provokes loud groans from others who complain they don’t have the time to deal with the minutiae. The study itself has some vocal critics who took issue with the methodology, but the authors likewise acknowledge several limitations with the research. For one, the study is observational so it can’t prove causation. However, it also may give hope to those who want to try it.

Focusing on Consistent Trackers

Tracking, even less than daily, was associated with weight loss, said Sergey Oreshko, MEng, co-founder and CEO of MyNetDiary, Boca Raton, Florida, who conducted a retrospective cohort analysis of the users who signed up for the app.

“The more days per week a person tracked the more weight was lost,” Oreshko said in an interview with Medscape Medical News. Those who tracked 6-7 days a week lost over 11% of their body weight over the 6-month study, he said. But tracking less often also provided benefits, with those tracking 2 days a week losing over 6% of body weight.

Oreshko and his co-author, Susan Heikkinen, RD, a registered dietitian with the company, first looked at 412,193 new users who had signed up during May 2025. Next, they applied filters, including users with a weight-loss goal, those with 21 or more in-window food-logging days over the study period, those who recorded their weight monthly and those who were 18 years or older. Excluded were those who lost more than 30% of their weight or gained more than 10%, who would likely be outliers.

The final group had 5132 mobile app users.

The primary outcome was percentage body weight change over the 6 months, and the secondary outcomes were loss of 5% or more and loss of 10% or more.

• Of those tracking 2-3 days a week, 56.5% achieved the clinically significant 5% threshold.
• Of those tracking 6-7 days a week, 80% lost 5% of weight.
• Over the entire group, the average user lost about 20.5 pounds, or 9.5% of body weight, and 70% lost at least 5%, whereas 44.8% lost 10% or more of body weight. And 9% gained weight.
• Each additional tracking day per week was associated with higher odds of 5% or more weight loss in the adjusted model, they found (adjusted odds ratio, 1.35, 95% CI, 1.31-1.40; P < .001).

Experts: Criticism and Kudos

“It has been known for decades that tracking leads to supporting successful weight loss,” said Christopher Gardner, PhD, director of nutrition studies at the Stanford Prevention Research Center, Stanford University School of Medicine, Palo Alto, California, who reviewed the study for Medscape Medical News. The challenge, he said in an email interview, is that many people don’t track consistently or for a long enough time for it to be useful.

He took issue with the methodology, especially the small group studied — less than 1% of the original cohort. As a result, “these results are not generalizable,” he said.

The authors acknowledge that as well, also pointing out it’s an observational study so can’t prove causation and that the more motivated trackers both tracked more and lost more. They also didn’t measure the use of GLP-1 receptor agonists so that may account for some of the loss as well, they said.

The study can’t establish whether the frequent tracking causes the weight loss or whether early success drives continued tracking, said Silvana Obici, MD, chief of endocrinology at Stony Brook Medicine and medical director of the Diabetes Services at Stony Brook University Hospital, Stony Brook, New York, who also reviewed the study. The logging behavior and the outcome are both markers of engagement and motivation.

“People who are losing weight are more likely to keep logging, and people who log more are, by selection, more motivated and adherent. This is the major limitation of this and other studies of this type.”

Another obesity expert agreed that the findings are not generalizable but said the research findings do offer some valuable information.

“Not generalizable is not the same as not useful,” said Kevin Gendreau, MD, an obesity medicine and family medicine clinician at the Weight & Wellness Center at Signature Healthcare in Brooklyn, Massachusetts.

What might especially come as a pleasant surprise, he said, is that “the bar is lower than people assume. The 2-3 day per week group still did well. Most people hear ‘food tracking’ and picture logging every bite forever, then quit in week 2 when they miss a day! Knowing that imperfect tracking still counts is probably the most useful thing anyone takes from this study.”

Is There a Successful Tracker ‘Type?’

“People have very different relationships with tracking,” said Rachel Goldman, PhD, a psychologist and clinical assistant professor at the NYU Grossman School of Medicine, New York City.

“Some people actually love it because it gives them concrete information about what they are eating,” she said. Tracking can also make people aware of how much they are eating and identify patterns they might otherwise miss.

“There are also people who are naturally more organized, detail-oriented, or data-driven and enjoy having that structure.” At the other end of that spectrum, she said, are those who complain that tracking is just one more thing they have to do.

“I emphasize that tracking is not necessary for everyone, and it should be used in a way that feels supportive rather than stressful,” said Monica Kelly, RD, registered dietitian at Montefiore Einstein, Bronx, New York. “Many free and low-cost tracking apps are available, giving people flexibility to choose the approach that works best for them.”

It’s also important for clinicians to anticipate who might struggle with tracking, Obici said. That may include patients who are high in avoidance or distress, who engage in emotional eating or who are low in self-efficacy, she said.

‘It’s a Mindset’

For some regular trackers, it’s become a habit they don’t complain about.

On a recent weekday, Jonah Kubela, 31, was waiting for his WW (formerly Weight Watchers) meeting in Burbank, California, to begin. He joined in 2022 to lose weight, and, he said, “got more serious about tracking in 2024.” Tracking is a foundation of the program, available on a smartphone app.

Kubela tracks most days. He has lost weight but is not yet to his goal. He’s committed to tracking. “It’s just having the mindset,” he said.

Sitting nearby, Caroline Boles, 78, of Glendale, agreed. She’s achieved WW lifetime status, which requires getting to goal weight and staying there. “I track 3 or 4 days a week,” she said. What motivates here? “It’s a health thing, and I don’t want to keep buying new clothes.”

Goldman reported being an advisor for online health and wellness site Ro. None of the other sources reported any relevant disclosures.