Family-Based Interventions to Promote Weight Management in Adults: Results From a Cluster Randomized Controlled Trial in India

Dear Editor,

We have read with great interest the article by Panniyammakal et al. (1) reporting on a cluster randomized controlled trial of family-based interventions for weight management in Indian adults. We write as family physician researchers in Spain, where we frequently confront the rising prevalence of obesity and the associated burden of noncommunicable diseases in our daily practice. This study’s methodology, particularly the use of nonphysician health workers to deliver integrated, family-oriented counseling, offers a valuable perspective on how to leverage existing community structures in primary care settings to promote lifestyle changes. The results show meaningful decreases in weight, body mass index, and waist circumference after two years, outcomes that warrant careful attention for their applicability to other healthcare contexts.

One aspect that particularly resonates with our practice is the concept of embedding prevention and health promotion within the family environment. In Spain, a considerable proportion of patient visits in primary care revolve around chronic conditions closely linked to lifestyle, such as type 2 diabetes and hypertension, which are often exacerbated by obesity. We believe that a family-based approach could be harmonized with our current care model if adapted to local cultural and infrastructural circumstances. Indeed, there is prior evidence that family interventions can yield significant benefits in chronic disease management when implemented consistently (2). In the study by Panniyammakal et al. (1), the structured follow-up and high level of participant engagement underscore the importance of both individual and collective responsibility in health-related decision making. In our experience, engaging family members in health goals is an important motivator for sustainable behavioral change, and the Spanish context, characterized by strong family ties, may favor similar outcomes if the model is implemented thoughtfully.

In practical terms, adapting this intervention to the Spanish health system would require close coordination among general practitioners, family nurses, and community health workers, reminiscent of the approach taken in India with the accredited social health activists. Currently, in many Spanish primary care settings, there are equivalent figures—sometimes through nursing and social work teams—who already maintain contact with patients outside the typical medical encounter, albeit not always in structured, repeated home visits. This approach would align with the longstanding emphasis in Spanish public health on community-based interventions, as exemplified by programs of the Sociedad Española de Medicina de Familia y Comunitaria (semFYC) and by the Programa de Actividades Preventivas y de Promoción de la Salud (PAPPS). However, these programs are often less intensive than the one described in the article, which raises the question of sustainability and potential resource allocation. A systematic review by Lemstra et al. (3) demonstrated that higher adherence to weight loss and lifestyle interventions is associated with more frequent follow-up and individualized feedback, suggesting that the time- and labor-intensive nature of the PROLIFIC intervention may be an important reason for its success.

It is also essential to highlight the roles of nonphysician personnel and the feasibility of introducing them more broadly into the Spanish system. The authors describe that the nonphysician health workers not only screened for risk factors but also engaged the entire family in goal setting for diet and physical activity. This is reminiscent of previously successful chronic disease self-management programs in other settings, such as that described by Lorig and colleagues (4), in which lay educators played a crucial part in guiding patients to assume greater responsibility for their health. The lessons from India may thus be transposed to Spain by empowering existing staff to coordinate extended home visits, document progress, and facilitate peer groups for individuals with established chronic conditions. In many of our primary care centers, forming such groups is common practice, but they remain limited in scale and are often targeted at specific cohorts (for instance, group visits for type 2 diabetes) rather than entire families.

Another valuable element of the study is the analysis of anthropometric measures as feasible and objective indicators of the intervention’s effectiveness. Weight, waist circumference, and body mass index can be easily recorded in most primary care visits, making them suitable outcomes for ongoing audits and feedback processes within our context. In addition, the article cites prior evidence that reducing central obesity is linked to decreased incidence of type 2 diabetes (1), which is consistent with earlier data from large-scale trials such as the Diabetes Prevention Program in the United States, where lifestyle interventions lowered diabetes risk and contributed to meaningful weight reduction (5). This underlines the potential long-term impact that family-centered programs could have on Spain’s broader noncommunicable disease burden.

Furthermore, while the trial in India was not blinded due to its pragmatic nature, its methodological rigor stands out for employing cluster randomization at the family level and ensuring independent teams collected outcome measures. Such attention to detail can inspire confidence in the internal validity of the findings and strengthens their potential relevance across different countries. We appreciate that some differences in educational level and socioeconomic background between participants in the intervention and control arms were recognized, which the authors addressed using robust statistical methods. In Spain, where many regions have heterogeneous populations, a similarly meticulous approach would be necessary. Stratifying by socio-demographic variables might be crucial to detecting differential impacts across urban and rural areas, as well as across the diverse cultural backgrounds we encounter in our practice.

In addition, focusing on family ties can transform a standard individual counseling session into a more comprehensive and coherent lifestyle intervention. Evidence-based reviews have shown that collective efforts—such as those centered on meal preparation, group exercise, and shared goal setting—reinforce adherence by improving motivation and accountability among participants (3). Indeed, one of the limitations repeatedly cited in weight management interventions is the difficulty participants have in sustaining lifestyle changes over time, particularly when they face environmental or cultural factors that do not align with healthy behaviors. A family-based approach can mitigate these issues by promoting joint decision-making about meal planning, shared physical activity routines, and reciprocal support during challenging phases.

Yet, the question of how to fund and manage family-based visits in Spain persists. Our National Health System places a strong emphasis on universal coverage and equitable access, but it also operates under budgetary constraints that often limit the number of personnel dedicated to preventive measures. As the World Health Organization’s global action plan on noncommunicable diseases highlights, allocating resources to prevention can generate long-term savings by reducing costly complications (6). Still, immediate cost considerations frequently determine where investments are made. A potential solution would involve pilot programs in selected health districts, employing a handful of nonphysician health workers who receive specialized training in motivational interviewing, nutritional counseling, and physical activity promotion. These programs could be evaluated rigorously, following the approach outlined by Whitlock et al. (7), which emphasizes systematic assessment of behavioral counseling interventions in primary care.

Another dimension is technological integration. While the Indian intervention utilized home visits and health diaries to track goals, a complementary strategy in Spain could incorporate digital tools and telemedicine, capitalizing on the widespread use of smartphones and internet access. This might decrease the manpower requirement for routine follow-up visits while maintaining regular contact with families. However, it would be important to confirm that all family members can use or access these technologies, and to measure whether electronic reminders, group messaging platforms, or digital diaries can achieve comparable or better adherence results than manual approaches.

Lastly, we share the authors’ view that shifting attention from individual to collective behavioral changes can deliver broader public health benefits. Family-based interventions offer a chance to address not only overweight and obesity but also related modifiable risk factors, thereby exerting a positive influence on diabetes, cardiovascular risk, and other lifestyle-related conditions. Taken together, these outcomes could reduce the burden on primary care services by limiting the progression of chronic diseases. Considering the encouraging evidence in the article by Panniyammakal et al. (1), we support further cross-cultural research and encourage Spanish policymakers to consider experimental pilot studies adapting these family-based models to our healthcare environment.

In conclusion, we commend the authors for conducting a rigorous trial that underscores the value of incorporating family-centered strategies into weight management programs. Their results highlight the promise of frequent household visits, collective goal setting, and sustained follow-up for reducing obesity-related measures in high-risk adults. We believe that Spain’s existing primary care framework, with its wide population coverage and ethos of continuous care, could be conducive to adopting similar approaches with appropriate adaptation. By engaging professionals across disciplines, exploring feasible financing models, and leveraging available technologies, there is a unique opportunity to translate the positive outcomes from the Indian context into practical, evidence-based interventions that could benefit our communities in Spain.

REFERENCES:

1. Panniyammakal J, Stanley A, Ismail S, Lekha TR, Ganapathi S, Harikrishnan S. Family-Based Interventions to Promote Weight Management in Adults: Results From a Cluster Randomized Controlled Trial in India. Ann Fam Med. 2025 Mar 1;23(2):93–9.

2. Kitzmann KM, Dalton III WT, Stanley CM, Beech BM, Reeves TP, Buscemi J, et al. Lifestyle interventions for youth who are overweight: A meta-analytic review. Health Psychol. 2010;29(1):91–101.

3. Lemstra M, Bird Y, Nwankwo C, Rogers M, Moraros J. Weight-loss intervention adherence and factors promoting adherence: a meta-analysis. Patient Prefer Adherence. 2016 Aug 12;10:1547–59.

4. Lorig KR, Sobel DS, Stewart AL, Brown BWJ, Bandura A, Ritter P, et al. Evidence Suggesting That a Chronic Disease Self-Management Program Can Improve Health Status While Reducing Hospitalization: A Randomized Trial. Med Care. 1999 Jan;37(1):5.

5. Group DPPR. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002;346(6):393–403.

6. Noncommunicable Diseases, Rehabilitation and Disability (NCD. Global action plan for the prevention and control of noncommunicable diseases 2013-2020 [Internet]. World Health Organization; [cited 2025 Apr 12]. Available from: https://www.who.int/publications/i/item/9789241506236

7. Whitlock EP, Orleans CT, Pender N, Allan J. Evaluating primary care behavioral counseling interventions: An evidence-based approach 1. Am J Prev Med. 2002 May 1;22(4):267–84.