Researchers studied what happens when people lose weight and then gain it back repeatedly—a pattern called weight cycling. They found that people who keep their weight stable after losing it have better health outcomes and save money on medical bills. The study looked at whether a high-protein supplement could help people maintain their weight loss after using a popular diabetes medication (GLP-1) that helps with weight loss. The results suggest that staying at a stable weight is much better than the up-and-down cycle, and using the right tools to maintain weight loss could save the healthcare system thousands of dollars per person.

The Quick Take

  • What they studied: Does repeatedly losing and gaining weight (weight cycling) cause more health problems and higher medical costs than keeping weight stable? Can a high-protein supplement help people maintain weight loss?
  • Who participated: The study used computer models to simulate what would happen to adults with obesity (BMI of 30 or higher). It compared people who cycle through weight loss and gain versus those who maintain a stable weight.
  • Key finding: People who maintained stable weight after losing it had fewer health problems, lived longer, and cost the healthcare system about $4,600 less per person than those who cycled their weight up and down. Using a high-protein supplement with weight loss medication was cost-effective, costing about $24,000 per year of healthy life gained.
  • What it means for you: If you’re trying to lose weight, the goal shouldn’t just be losing it—it should be keeping it off. Using strategies like high-protein supplements after weight loss medication may help you maintain your results and reduce your risk of weight-related diseases. However, this research is based on computer models, not real people, so results may vary.

The Research Details

This study didn’t involve actual patients. Instead, researchers used computer models to predict what would happen to people with obesity over their lifetime. They created two scenarios: one comparing people who repeatedly lose and gain weight versus those who keep weight stable, and another testing whether a high-protein supplement could help maintain weight loss after using GLP-1 medication (a popular weight loss drug). The computer model tracked monthly changes in health status, disease development, and costs over a person’s entire life. Researchers used information from previous studies to estimate how likely people were to develop obesity-related diseases like diabetes, heart disease, and certain cancers.

The study looked at costs and health benefits from a ‘societal perspective,’ meaning they counted all healthcare costs, not just what insurance pays. They adjusted their calculations for the impact of weight cycling and other risk factors. To check if their results were reliable, they ran the model multiple times with different assumptions to see how sensitive the results were to changes in their estimates.

This research approach is important because it allows researchers to predict long-term health and economic outcomes without waiting decades for real-world results. By using computer models based on solid scientific evidence, they can estimate the true cost of weight cycling and the value of weight maintenance strategies. This helps doctors, patients, and insurance companies make better decisions about which weight loss approaches are worth the investment.

The study’s strength comes from using data from multiple previous research studies (meta-analyses) to build their computer model. However, the main limitation is that it’s based on predictions, not actual patient experiences. The results depend heavily on the accuracy of the data they used to build the model. The study was transparent about uncertainty by running sensitivity analyses to test how different assumptions would change the results. The research was published in BMJ Open, a reputable medical journal, which suggests it went through peer review.

What the Results Show

The study found that people who maintained a stable weight after losing it had significantly better health outcomes than those who cycled through repeated weight loss and regain. Specifically, non-cyclers (people who kept weight off) experienced about 0.09 fewer obesity-related health events, lived about 7 months longer, and had better quality of life compared to cyclers. Most importantly, this translated to approximately $4,600 in healthcare cost savings per person over their lifetime.

In the second part of the study, researchers tested whether combining GLP-1 medication (a weight loss drug) with a high-protein supplement for weight maintenance was cost-effective. They found it was, with a cost of about $24,276 per year of healthy life gained. To put this in perspective, the US healthcare system generally considers treatments cost-effective if they cost less than $100,000 to $150,000 per year of healthy life gained. This means the combination treatment was well within acceptable cost-effectiveness ranges.

The results suggest that weight cycling creates a harmful cycle: people who repeatedly lose and gain weight develop more obesity-related diseases, live shorter lives, and cost the healthcare system more money. Using proven strategies to maintain weight loss—like high-protein supplements—appears to break this harmful cycle and provides good value for the money spent.

The study also examined how different factors affected the results. Weight cycling appeared to increase the risk of developing multiple obesity-related conditions simultaneously, which compounds health problems and costs. The research showed that the benefits of weight maintenance were consistent across different age groups and risk profiles. The high-protein supplement strategy was particularly valuable because it provided a practical, evidence-based tool for people to use after weight loss medication, helping them avoid the common problem of regaining weight after stopping medication.

This research builds on growing evidence that weight cycling is harmful. Previous studies have suggested that yo-yo dieting may increase health risks, but this is one of the first studies to calculate the actual economic impact in the US healthcare system. The findings align with other research showing that GLP-1 medications are effective for weight loss, and this study adds new information about the importance of weight maintenance strategies after initial weight loss. The cost-effectiveness results are consistent with other studies showing that weight management interventions provide good value compared to other healthcare treatments.

The biggest limitation is that this study used computer models rather than following real people over time. Computer predictions can be wrong if the data used to build them is inaccurate. The study assumed certain patterns of disease development that might not apply to everyone. It also didn’t account for factors like individual differences in how people respond to treatment, changes in medication costs over time, or new treatments that might become available. The study focused on the US healthcare system, so results may not apply to other countries with different healthcare costs. Finally, the study didn’t include real-world factors like how difficult it is for people to stick with high-protein supplements or how side effects of medications might affect people’s ability to maintain weight loss.

The Bottom Line

If you have obesity and are considering weight loss treatment, focus on finding a sustainable approach that helps you maintain weight loss long-term, not just lose weight quickly. Using GLP-1 medication combined with a high-protein supplement appears to be a cost-effective strategy (moderate confidence). Work with your healthcare provider to develop a weight maintenance plan before you finish active weight loss treatment. Avoid the trap of rapid weight loss followed by regain, as this pattern appears to cause more health problems than maintaining a stable weight, even if that weight is higher than your goal (moderate-to-high confidence).

This research is most relevant for adults with obesity (BMI 30 or higher) who are considering weight loss treatment or have recently lost weight. It’s also important for healthcare providers, insurance companies, and policymakers deciding which weight loss treatments to support. If you have a BMI under 30 or are at a healthy weight, this research is less directly applicable to you. People with certain medical conditions that prevent them from using GLP-1 medications should discuss alternative weight maintenance strategies with their doctor.

Based on this research, you shouldn’t expect immediate results. Weight cycling’s harmful effects build up over years and decades. However, if you switch from a cycling pattern to maintaining stable weight, you should see improvements in disease risk factors (like blood sugar and blood pressure) within weeks to months. Significant reductions in obesity-related diseases and healthcare costs would take years to develop. Think of this as a long-term investment in your health rather than a quick fix.

Want to Apply This Research?

  • Track your weight weekly (same day, same time) and calculate your 4-week average to identify weight cycling patterns. Set a target weight range (±3-5 pounds) rather than a single number, and monitor how often you stay within that range. This helps you see whether you’re maintaining weight or cycling.
  • Use the app to set reminders for taking your high-protein supplement at the same time daily, especially after completing weight loss medication. Log your protein intake to ensure you’re meeting daily targets (typically 25-30% of calories from protein). Create a maintenance plan in the app that includes specific strategies for preventing weight regain, such as regular weigh-ins, meal planning, and exercise tracking.
  • Set up monthly check-ins in the app to review your weight trend over the past month. Track not just weight, but also how you feel, energy levels, and any obesity-related symptoms (like joint pain or shortness of breath). Use the app’s trend analysis to identify early warning signs of weight cycling (rapid ups and downs) and adjust your maintenance strategy before regain becomes significant. Share these trends with your healthcare provider during regular visits.

This research is based on computer models and predictions, not studies of actual patients over time. The results may not apply to everyone, and individual outcomes depend on many factors including your specific health conditions, medications, and ability to follow a weight maintenance plan. Before starting any weight loss medication or supplement, consult with your healthcare provider to discuss whether it’s appropriate for you, potential side effects, and how to maintain weight loss safely. This information is educational and should not replace professional medical advice. Always work with your doctor to develop a personalized weight management plan.