The timeframe for experiencing noticeable effects from vitamin B12 supplementation varies considerably based on several factors. These include the severity and duration of the deficiency, the route of administration (oral, sublingual, injection), and individual metabolic differences. A mild deficiency may resolve relatively quickly, while a more severe, long-standing deficiency can require extended treatment to correct.
Vitamin B12 is essential for numerous bodily functions, including red blood cell formation, neurological function, and DNA synthesis. Insufficient levels can lead to fatigue, weakness, neurological problems like numbness or tingling, and anemia. Historically, pernicious anemia, a condition caused by B12 malabsorption, was a serious and potentially fatal illness before the discovery of effective B12 therapies.