Innovative Hydrogels: A Novel Approach to Tackle Obesity and Its Associated Health Risks.

Obesity, considered a chronic and multifactorial disease, is one of the most urgent public health challenges, affecting about 13% of the global population. It is strongly associated with comorbidities such as type 2 diabetes, hypertension, cardiovascular disease, and certain types of cancer. Conventional management strategies, including lifestyle interventions, pharmacotherapy, and bariatric surgery, often provide limited or short-term benefits that encompass adverse effects or poor adherence depending on the patients' response. Hence, there is a need for innovative and minimally invasive treatments. In this context, hydrogels have emerged as promising and versatile platforms. Hydrogels are biocompatible three-dimensional polymeric networks that absorb and retain large amounts of water inside their structure. They can be engineered as stimuli-responsive materials in response to environmental changes, including pH, temperature, and enzymes. These capabilities position hydrogels as malleable tools applicable across several obesity-related fields, ranging from controlled drug delivery and gastric volume modulation to the development of nontoxic ingestible systems. Recent advances highlight superabsorbent hydrogels that expand in the stomach to induce satiety; targeted hydrogels that deliver antiobesogenic compounds; and smart hydrogels that integrate nanomaterials to enhance mechanical strength and functionality. This review summarizes the classification of hydrogels, fabrication processes, and principal characteristics required in the biomedical field. The current evidence for hydrogel development as a basis for obesity management is analyzed, focusing on the main results from preclinical and clinical trials. Finally, hydrogels are highlighted as multifunctional and transformative platforms that offer new strategies to overcome the limitations and drawbacks of current obesity treatment therapies.