Is it bad to use expired vitamin e oil?

Just not as effectiv: All chemical compounds deteriorate with time and become less potent. Generally, medications have a predicted effective-shelf-life. Fortunately meds often don't spoil, but can become less and less effective being left in cabinet too long after expiring. So, it may not be bad to take, but it may not have as much therapeutic value if expired too long. Consult doc. Good luck.