A great little nut, I feel it is often overlooked in favor of other more popular (and equally healthy!) nuts like almonds & walnuts. It seems like it's always the one left at the bottom of a jar of mixed nuts, discarded to be eaten only as a last resort, the poor little thing!
Brazil nuts are a great source of thiamine and magnesium and are one of the best sources of the antioxidant selenium, the last of which is associated with reduced rates of breast and prostate cancer.
They do have the highest saturated fat content of all the nuts, so keep that in mind before eschewing all other nuts from your diet. As with everything else- keep it balanced and varied as much as possible!
Try brazil nuts wherever you'd normally use other nuts; atop a salad, blended into a fruit smoothie or as an easy snack with some fresh fruit.