Thank you for shining a light on the vital role vitamin B12 plays in the body, Dr. Yildiz. I've been taking the sublingual supplement for many years. It would be good if doctors routinely tested for B12 deficiency.

It's good you encourage people to take responsibility for their health and advocate for themselves. People often worry their doctor will think they are being a nuisance and don't speak up about health concerns or ask for the tests they need.

My dad was a doctor and two things he taught me to do are:

1. Keep your own health records, do research online before your medical appointments and ask for the tests that might help diagnose or treat your condition.

2. Speak up and be honest about your health concerns and don't be afraid to get a second opinion. "It's the squeaky wheel that gets fixed."