I am a 49-year-old woman. After feeling sick, run down, generally unwell, with erratic moods and unexplained, random pain, I had a full physical seven months ago. The extensive blood labs showed my B12 levels were very low, but my iron profile was perfectly normal. I was also very deficient in Vitamin D, and I take a prescription supplement for that.
The doctor put me on an oral B12 supplement and I take it daily, in addition to a combination B-vitamin supplement I've taken for a few years. My diet has been excellent, balanced, and healthy--no junk--for many years. I am 99% a vegetarian, but I eat fish once a week, and I regularly eat eggs, cheese, and yogurt.
So, why isn't my body holding onto the B12 I consume in my diet? Now that I've been taking 2,000 mcg B12 daily for seven or eight months, I expected to feel better, but I don't. How long does it take for these supplements to provide noticeable benefits?