I just took a b12 injection. how long does it stay in your system.

The answer: depends on your own individual metabolism and your dietary habits. If you eat a lot of processed foods, chances are the chemicals contained within these products will interfere with your intestinal absorption of this vitamin. Injections bypass that problem. Most injections last about a month on average. The amount of B12 in your body also depends on how much is stored by your liver .

Up to a year: It depends on the dose and the state of your liver. A large dose, e.g., 2000 micrograms may last a year. However, it you are unable to absorb B12 from food, you should get injections every three months or so. Wish you good health! - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.