Visit farms regularly, get plenty of sunlight (or Vitamin D), and have a stimulating environment (seems Lamarckian).
See:
SciDaily: Farm Moms May Help Children Beat Allergies
PhysOrg: Sun In Pregnancy Builds Stronger Bones For Baby
TechReview: A Comeback for Lamarckian Evolution? Two new studies show that the effects of a mother's early environment can be passed on to the next generation.
