I was shocked when I went to my doctor yesterday. A normal level of B-12 is between 350-1000 (although Japan recently raised their levels to 500 for the low range). Mine was 247.
When I read the list of symptoms, I was amazed at how many I was experiencing. B-12 deficiency didn't even register on my radar. Suddenly I learned how important this particular B vitamin is. I learned it the hard way.
Just to list some of the possible symptoms: memory loss, numbness in the hands and feet, eye twitches, migraine headaches, depression, fatigue.
I thought I had a case of mild depression that I just couldn't seem to recover from. I was always tired and had started forgetting things (which unfortunately is also listed as a depression symptom). I have always had migraine headaches, and I didn't think anything of the minor eye twitches I would get from time to time.
I had no idea that B-12 deficiency is common in up to 30% of the population and can lead to severe brain and nerve damage if left untreated. I just assumed that I had always been a little clutzy.
If you or someone you love seems to be tired and lethargic all the time, have your doctor check B-12 levels. It takes two blood tests, and even borderline results (under 500) can cause symptoms in some people.