  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. 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
$\alpha$-diversity compared with casein and chickpea isolate groups while
chickpea flour, had the greatest distinction in $\beta$-diversity. Alternative
protein sources supported optimal growth, but quality and health implications
require further exploration.
