Pre-clinical evidence for plant and insect proteins in supporting growth and bone development

By 2050, the global population will exceed 9 billion, demanding a 70% increase in food production. Animal proteins alone may not suffice and contribute to global warming. Alternative proteins such as legumes, algae, and insects are being explored, but their health impacts are largely unknown. For this, three-week-old rats were fed diets containing 20% protein from various sources for six weeks. A casein-based control diet was compared to soy isolate, spirulina powder, chickpea isolate, chickpea flour, and fly larvae powder. Except for spirulina, alternative protein groups showed comparable growth patterns to the casein group. The Spirulina group demonstrated 17% lower body weight and 9% lower body and femur length. Morphological and mechanical tests of femur bones matched growth patterns. Caecal 16S analysis highlighted the impact on gut microbiota diversity. Chickpea flour showed significantly lower α-diversity compared with casein and chickpea isolate groups while chickpea flour, had the greatest distinction in β-diversity. Alternative protein sources supported optimal growth, but quality and health implications require further exploration.