Decreases in Collinsella have clear implications for human health as increased Collinsella abundances are linked with low fiber intake and correlated to circulating insulin [41], in increased abundances in the gut microbiome of patients with atherosclerosis [42], shown to increase gut permeability and be associated with rheumatoid arthritis [43], and known to be proinflammatory and a risk factor for Alzheimer’s disease [44]. This evidence concerns the gene INS and early-onset autosomal dominant Alzheimer disease.