Vitamin B12 is an important nutrient that provides a number of functions that are crucial for optimal health. These benefits include the creation and support of red blood cells, the maintenance of DNA, and proper brain and nervous system function. Because the body does not produce vitamin B12 on its own, you must be intentional about getting the proper amounts from animal food products or through the use of supplements.

Here are a few of the most common signs that could signal a deficiency in vitamin B12.
 

Cognitive Decline Issues

Emerging research is increasingly pointing to a lack of vitamin B12 with an increased risk of dementia symptoms, including a higher threat of Alzheimer's disease. This onset may manifest itself through a marked increase in irritability, memory loss, mood swings, and hallucinations. While some level of memory loss and cognitive decline is normal as you age, a sufficient intake of vitamin B12 may help to slow the progression of this issue.
 

Extreme Fatigue

Because the production of red blood cells is one of the primary functions of vitamin B12, it makes sense that you would experience fatigue if you are not getting enough of the nutrient. This is because red blood cells work to carry the oxygen throughout the body, delivering energy and helping you to feel your best. A deficiency in vitamin B12 translates to fewer red blood cells available to move this oxygen, resulting in a sense of weakness or fatigue. In addition, vitamin B12 is also instrumental in energy metabolism, further compounding the issue of fatigue when deficient.
 

Anemia

Related to a decrease in red blood cell production is the major health issue of anemia. Also known as low hemoglobin, this condition can leave you feeling weak and tired. Specifically, not getting enough vitamin B12 is connected with macrocytic anemia, a condition in which the red blood cells become too large. Anemia can lead to a number of health issues, including cold intolerance, insomnia, mood disorders, and lethargy.
 

Nerve Cell Damage

Notice the presence of tingling or numbness in the hands or feet? Nerve cell damage is one of the more serious complications of a lack of vitamin B12 intake. This is because the vitamin is crucial for the optimal health of the myelin sheath, the protection around the nerves. This myelin may swell and break down if the body does not have enough vitamin B12, leading to severe nerve damage. The tingling or numbness is a result of this breakdown.
 

Glossitis

Glossitis is a condition in which the tongue becomes swollen and inflamed. The surface of the tongue will then become smoother, leading to tenderness of the area. Some people may also notice the inability to taste when suffering from glossitis. The condition may also manifest as a cracked and red tongue. Rare symptoms of this health issue include problems chewing or speaking.
 

Shortness of Breath

In extreme cases, some individuals may notice a shortness of breath when deficient in vitamin B12. This is related to the ability of the red blood cells to effectively move oxygen through the muscles. An additional complication of this is the presence of dizziness, both acute and long-term.
 

Foods High in Vitamin B12

Now that you know some of the most common signs of a vitamin B12 deficiency, you may be wondering what you can do to ensure that you are getting adequate amounts of this nutrient. You will find vitamin B12 in plentiful amounts in a variety of shellfish. Other types of seafood and fish are also high in this vitamin.

Red meat, liver, milk, and eggs are additional foods that will provide a good boost of vitamin B12. Another easy way to ensure you are getting enough of this vitamin is to choose the right fortified foods. You will find varying amounts of vitamin B12 in fortified foods such as cereal, tofu, and plant-based milks.

As with all vitamin deficiencies, it can be difficult to pinpoint the resulting health issues. Working with a nutritionist or a dietician can help you to isolate what may be causing your health issues and if paying closer attention to your intake of certain vitamins can help to alleviate the complications.