Table 4.

Alpha diversity results

Diversity measure	HEI	MDS	HFD-Index
Chao1	−0.01⊥	> 0.00⊥	− 0.05**
OTUs	0.06**	0.05*	− 0.05*
Shannon	0.1***	0.07***	− 0.01⊥
Simpson	0.06**	0.05*	− 0.01⊥

Standardised coefficients of linear mixed-effects models of three dietary indices, the Healthy Eating Index (HEI), Mediterranean Diet Score (MDS) and the Healthy Food Diversity index (HFD-index), against four measures of alpha diversity (Chao1, Observed number of OTUs (OTUS), Shannon diversity and Simpson’s diversity index). Alpha diversity measures were rarefied and adjusted for BMI, sex, age and technical covariates (see the “Methods” section). p values: *p < 0.05, **p < 0.01, ***p < 0.001, ⊥ = non-significant