I am vegan and only eat whole foods (fruit, veg, whole grains, beans, etc.), and i drink 2-3 l h2o/day, yet i've been constipated recently. what's up?

Exercise,hydrate mor: drink more juices and sport drink like Gatorade in addition to the water, in summer we need at least 6-7 liter of fluid assuming you do not work outdoors,electrolyte problems could cause a laziness in the bowel that will lead to a constipation.exercise is very important in the health of the digestive system , so have your share of daily exercise even by a simple walking. Good luck.

A few possibilities: You're correct that a diet rich in fruit, vegetables, fiber & water should prevent constipation. However, some vegetables (like cruciferous veggies, esp. raw) can suppress thyroid function and hypothyroidism can cause constipation- see http://tinyurl.com/koyamo5 An imbalance of Gi flora (including yeast overgrowth & certain parasites), magnesium deficiency & stress are among other possible causes.