My doctor ran a serum B12 test, because of my symptoms:
Pins and needles and numbness in arms, legs, hands, feet.
Pins and needles in chest
Pain in arms and legs
Fatigue, weakness and unusual exhaustion
Slowed ability to walk
Shortness of breath when walking
Difficulty walking up stairs, slopes
Difficulty concentrating, remembering, confusion
Slowed digestion, heartburn
Blurry vision in one eye
All my blood tests have come back within the normal range, for the most part.
B12 was 620, MCV was 84, RBC 4.8, HBG normal.
RDW was 10.7
Ferritin was 45 last time I looked.
Thyroid tests (TSH, T4, Free T4, TPO) all normal.
Heart scans, XRays, and blood tests normal.
Before getting the results of the B12 test, he started me on B12 pills. Since starting them, my health has improved dramatically. Most of the symptoms are gone, but I still get some pins and needles from time to time, and the fatigue and weakness come half way through the day. I am only taking 250mcg of B12 a day.
It is very odd to me, since my serum B12 is normal, my MCV and RBC is normal, that the oral B12 would practically cure me. I am coming back from having several serious illnesses over the last four years, including cancer (considered cured), hyperparathyroidism, hyperthyroidism, and severe osteoporosis. Also several operations during those four years.
Does anyone have any explanation as to why B12 supplements would cure someone who isn't B12 deficient?