Is there a way to improve your memory?

My whole family seems to suffer with short term memory loss issues. It affects the way our kids read, the way my husband asks the same question 4 different times and doesn't remember the answer I gave him and my spaciness, We are vegetarians so I wonder if we are lacking something. We have a healthy diet. I would like to add flaxseed in for Omega's. I was told to make lists and use flash cards for the kids reading but there must be other tools.