How do you know which vitamin supplements you might need to take? This is a question that is, rightly, of great concern to many people. It is especially urgent when considering the many pronouncements that “supplements are useless,” or advice to “just eat a well-balanced diet.” It is no wonder this reader is confused.
Q. Several doctors over the years have put me on different vitamins. I now take a daily multivitamin with minerals as well as vitamins E, D3 and B12.
Is there a test that can show which vitamins I actually need?
A. There is no single test, but we agree that it is better to know whether you need additional vitamins than to take them willy-nilly.
Your doctor can test for vitamin B12 and vitamin D quite easily. If he or she suspects you are low in other nutrients, those tests can be run.
Tracking Down a Vitamin B12 Deficiency
Certain medications, such as metformin for diabetes or PPIs for acid reflux symptoms, can deplete the body of vitamin B12. People taking such drugs should be tested for this deficiency on a regular basis. If the doctor suspects a possible deficiency based on symptoms such as numbness or nerve pain, but the test results are not clear enough, the doctor may also order a test for methylmalonic acid (MMA). This rises as vitamin B12 falls.
There are also companies that sell at-home or walk-in lab tests for a number of vitamins and minerals. The results may give you a better sense of which supplements might be beneficial.
