An open-label clinical trial to investigate the safety and efficacy of a bone broth diet on weight loss in adults with obesity

<h2>Summary</h2><h3>Background and aims</h3> Over 40% of North American adults are obese and with rates increasing, an already significant public health concern is expected to get worse. Modifiable risk factors such as poor dietary habits represent an opportunity for targeted change. The Bone Broth Diet (BBD) combines the consumption of bone broth, portion-controlled, low carbohydrate and high protein meals, intermittent fasting, and exercise. <h3>Methods</h3> This open-label, single-arm clinical trial investigated the safety and efficacy of the BBD on weight loss in adults with obesity between 35–65 years old. Participants (n = 100) completed two, 3-week periods of 5:2 intermittent fasting (BBD 1 and 2), while consuming bone broth, for which each period was followed by a one-week maintenance period. Body weight, body composition, anthropometrics, metabolic blood markers, satiety and hunger, quality of life, and safety were assessed over the study period. <h3>Results</h3> There were respective decreases of 4.8 kg and 2.6 kg in body weight after BBD 1 and 2 which corresponded to 5.0% and 2.7% (<i>P</i> < 0.001), respectively. Both BBD phases were followed by periods of weight maintenance. These improvements corresponded with decreases in fasting blood glucose, waist circumference, and sagittal abdominal diameter (<i>P</i> ≤ 0.005). There were decreases in hunger and cravings (<i>P</i> < 0.05) with no reduction in satisfaction after eating over the study period (<i>P</i> > 0.05). The BBD was safe and tolerated in the studied population. <h3>Conclusion</h3> The BBD showed safe, statistically significant and clinically relevant weight loss with corresponding improvements in cardiometabolic and psychological health outcomes in a population of adults with obesity who were otherwise healthy. Findings suggest this lifestyle program may aid in addressing an important public health concern. However, future randomized controlled trials of longer duration are recommended to verify and understand the sustainability of results. <h3>Clinical trial registration</h3> This study is registered at clinicaltrials.gov (NCT05740670).