If your energy levels are on the fritz, your B-12 could be running a bit low. Vitamin B-12 doesn’t just give you energy, though. It also produces new red blood cells, helps your brain work at its best and maintains genetic material found in each cell. Checking your B-12 level isn’t a routine thing; your doctor may only run the lab if he suspects you have a shortage of the vitamin in your system.
Normally your vitamin B-12 level should fall somewhere between 200 and 900 pictograms per milliliter, or pg/mL, according to MedlinePlus. It’s very uncommon to have high B-12 levels, since abnormally high B-12 stems from severe chronic conditions like cirrhosis of the liver or certain types of cancer. But it is possible for B-12 to be on the lower end, even if you do your best to meet your daily recommendation.
Naturally occurring B-12 in animal foods is bound to proteins. When you eat meat, fish, eggs or other B-12-rich foods, acids in your stomach break the B-12 apart. But when you have pernicious anemia, your immune system attacks healthy cells in the walls of your stomach. Your stomach doesn’t produce much acid and the B-12 never gets a chance to break away. Plus, when these cells are destroyed, your body doesn’t have much -- if any -- intrinsic factor, which is a specialized type of protein that helps B-12 absorb. Much of the B-12 you’re getting from your diet passes right through without ever absorbing, resulting in an unusually low B-12 level.
Vitamin B-12 absorbs in your small intestine, its first stop after leaving your stomach. If you have some kind of bowel disorder though, the villi in your intestinal tract that pick up B-12 could be damaged. Crohn’s disease, celiac disease, irritable bowel syndrome or other chronic bowel issue can each contribute to a B-12 deficiency if your intestines are severely damaged.
Your body can store small amounts of B-12 for years in your liver. So even if you don’t make an effort to get the vitamin in your daily diet, your body should have enough to function. But because B-12 only comes from animal-based foods, a handful of fortified foods -- like breakfast cereal -- and supplements, if you follow a vegan type of diet, your B-12 levels could plummet over time. Talk with your doctor about your diet. You should have no problems adhering to your diet plan while meeting your B-12 needs, although your physician could suggest taking a vegan-friendly supplement or even give you a B-12 injection if you’re running low.
Melodie Anne Coffman specializes in overall wellness, with particular interests in women's health and personal defense. She holds a master's degree in food science and human nutrition and is a certified instructor through the NRA. Coffman is pursuing her personal trainer certification in 2015.