yes. conditions like crohn's disease and colitis which cause chronic inflammation of the colon can interfere with the absorption of certain vitamins or minerals leading to deficiencies. people with chronic acid reflux who take certain acid blockers may end up with too little stomach acid. as a result their digestive tracts can't absorb certain nutrients properly possibly leading to b12 deficiency and iron-deficiency anemia. an imbalance in the friendly bacteria that help break down food can cause vitamin or mineral deficiencies. chronic alcoholism may also lead to vitamin b and magnesium deficiencies. if you're worried that you may have a condition that affects your vitamin or mineral levels it's wise to talk to your doctor.
do some diseases cause vitamin or mineral deficiencies?