Smile for some minutes reinforces the immune system.
If the day was warm, she took the bear to the water. He showed no doggish enthusiasm when she went to get him, simply followed her docilely when she tugged this chain. Them, in the water, sat like a near-sighted baby placidly enjoying the return to liquid existence. (Bear, Chap. VIII, p. 42)
Sonreír unos minutos al día fortalece el sistema inmunológico.