Alpha diversity is associated with diet and exercise. (a) Average Shannon index was found to be higher among participants following a vegetarian diet (n = 6) compared to a nonvegetarian diet (n = 19; sanon, P = 0.004). (b) Average Shannon index increases with exercise time (minutes) per day. However, this effect was only among participants with an average exercise intensity of >1.5 (n = 17), where 1 = low, 2 = moderate, and 3 = high (linear regression, β = 0.026, P = 0.04, R2 = 0.29).