The amount of Vitamin B12 you may need will depend on your diet, exercise, your body's absorption efficiency, the form of B12 you take, and your current levels of B12. Many people have low absorption efficiency due to gut health issues such as IBS and Chron's, and medication. People following a plant-based diet will also have lower levels of B12.
The NRV for Vitamin B12 is only 2.5mcg per day, which is considered far too low for many people. B12 is a water-soluble vitamin, so any excess you take will be excreted by your body through urine.
The most important factor is to choose a methylated form of B12 called methylcobalamin, which is the most absorbable for your body. If you're correcting a deficiency, look for a dose of 2,000ug per day, or 2-3 times a week. If your B12 levels are more normal, a dose of 200ug that's found in our Women's ProMulti, or 500ug in our Men's ProMulti and Daily Multivitamin are ideal daily levels to support your energy, psychological function, red blood cell formation, reducing tiredness and fatigue, and much more.