Is fortified orange juice a good calcium alternative for people who are lactose intolerant? Also is it safe for people with bowel issues?

Calcium supplement. As long as you do not have any peptic disease such as reflux or gastritis it is ok to drink fortified OJ. keep in mind the amount of calcium in such beverages may not be adequate specially if you are trying to prevent osteoporosis and you may need to take additional calcium tablets daily . Lastly make sure your Vitamin D level is in the normal range as well ( blood test for 25-OH Vitamin D )