Researchers looked at 88 studies to see if phone apps that help people lose weight and exercise work equally well for everyone. They found that younger people and wealthier people are more likely to download and use these apps, but that doesn’t necessarily mean the apps work better for them. The study raises an important question: are these apps helping close the gap in health inequality, or making it wider? The researchers say we need to study how these apps affect different groups of people to make sure everyone benefits equally.

The Quick Take

  • What they studied: Whether weight loss and fitness apps work the same way for different groups of people, including those with different ages, incomes, and backgrounds.
  • Who participated: The review analyzed 88 real-world studies involving adults using mobile health apps. The studies looked at people from different age groups, income levels, genders, and other backgrounds.
  • Key finding: Younger people and those with more money were more likely to start using weight loss apps, but once people started using them, their success didn’t depend as much on age or income as expected.
  • What it means for you: If you’re thinking about using a weight loss app, it might work well for you regardless of your age or income—but the apps need to be designed so that everyone can actually access and use them, not just wealthy younger people.

The Research Details

Researchers searched five major medical databases for studies published through November 2023 that looked at real-world use of phone apps for weight loss, exercise, and reducing sitting time. They included 88 studies that tracked whether different groups of people actually used the apps and whether the apps helped them reach their health goals. Two researchers independently reviewed each study to make sure they were looking at quality research. The studies examined how factors like age, income, gender, race, and other characteristics affected whether people used the apps and if the apps actually worked.

Most previous research on weight loss apps came from controlled clinical trials where people are carefully selected and monitored. This can make results look better than they are in real life. By looking at real-world studies, researchers can see if these apps actually help all kinds of people, not just those in perfect study conditions.

This is a systematic review, which is a strong type of research that combines findings from many studies. The researchers used a careful process to find and evaluate studies. However, the quality depends on the studies they found—if those studies weren’t well-designed, the conclusions are less reliable. The researchers noted that many studies only looked at age, gender, and income, so we don’t know much about how apps work for other groups.

What the Results Show

The review found that younger people and those with higher incomes were more likely to download and start using weight loss apps. This makes sense because younger people tend to be more comfortable with technology, and wealthier people may have better access to smartphones and internet. However, once people started using the apps, these differences in age and income didn’t strongly predict whether the apps actually helped them lose weight or exercise more. This was surprising because researchers expected that wealthier, younger people would also see better results. The study found mixed results for other factors like gender, race, and education level—sometimes these made a difference, sometimes they didn’t.

The research identified two major barriers that prevent some people from using these apps: not having access to the right technology (like a smartphone or reliable internet) and not having the digital skills to use the apps effectively. Some groups of people, like those who have moved to a new country and people from LGBTQ+ communities, were almost never studied, so we don’t know how well apps work for them. The researchers also found that most studies only looked at whether people used the apps, not whether the apps actually changed their behavior long-term.

This review adds to growing evidence that just because an app is available doesn’t mean everyone can use it equally. Previous research suggested that technology-based health tools might widen health gaps between rich and poor, young and old. This study confirms that concern for app uptake but suggests the picture is more complicated—the apps might work similarly well once people start using them, but the real problem is getting everyone access and the skills to use them.

The study only looked at research that was already published, so studies showing negative results might be missing. Many studies didn’t report detailed information about who used the apps, making it hard to compare results. Most studies focused on age, gender, and income, leaving big gaps in knowledge about other groups. The studies varied widely in how they measured success, making it difficult to combine results. Finally, this review couldn’t determine cause and effect—it only showed which groups were more or less likely to use apps.

The Bottom Line

Weight loss and fitness apps appear to be helpful tools for behavior change across different groups (moderate confidence). However, before recommending apps to all patients, healthcare providers should consider whether their patients have access to smartphones, reliable internet, and the digital skills needed to use them (high confidence). Apps should be designed with input from diverse communities to ensure they work for everyone (high confidence). More research is needed to understand how apps work for people from different racial and ethnic backgrounds, immigrants, and LGBTQ+ individuals (high confidence).

Healthcare providers, public health officials, and app developers should care about these findings because they show that technology alone won’t solve health problems if not everyone can access it. People from lower-income backgrounds, older adults, and those without strong digital skills should know that these apps might require support to use effectively. Policymakers should consider these findings when deciding how to promote digital health tools.

If you start using a weight loss app, you might see changes in your behavior within 2-4 weeks, but meaningful weight loss typically takes 8-12 weeks. The key is consistent use—the app only works if you actually use it regularly.

Want to Apply This Research?

  • Track weekly app usage (number of days opened) alongside one behavior metric like steps walked per day or meals logged. This helps identify if barriers to app use are affecting your results.
  • Start with one simple goal in the app (like logging meals three times a week) rather than trying to do everything at once. This builds confidence and digital literacy gradually.
  • Check in monthly on whether the app is still working for you. If you’re struggling to use it, identify the specific barrier (too complicated, takes too long, doesn’t fit your life) and adjust your approach or try a different app rather than giving up.

This review examines how weight loss apps work for different groups of people but does not provide medical advice. Weight loss and fitness apps are tools that work best alongside professional medical guidance. If you have health conditions, take medications, or have concerns about starting an exercise program, consult your doctor before using any app. Results vary by individual, and apps work best when combined with other healthy behaviors like balanced eating and regular physical activity. This research does not replace personalized medical advice from your healthcare provider.