Signs of Low Vitamin B12 Levels in Adults

Vitamin B12 deficiency is one of the common nutritional deficiencies globally. Contrary to popular belief, it is not only vegans that may develop a vitamin B12 deficiency. Even vegetarians and meat eaters are at risk under certain circumstances and with certain conditions. Without proper nutrition or supplementation, low levels of vitamin B12 can have widespread effects on the body and some of these can be serious.

Who is at risk?

Vitamin B12 is abundant in animal foods. This includes meat, poultry, fish and seafood, eggs and milk/dairy. There are several reasons why a vitamin B12 deficiency may arise. People with one or more of the following risk factors are at a great risk of developing a vitamin B12 deficiency.

  • Insufficient vitamin B12 intake in food which is more common among vegans and to a lesser extent among vegetarians. The elderly are also mor likely to be affected due to dietary habits.
  • Chronic alcoholism which affects the digestive tract’s ability to absorb vitamin B12 from food. Alcoholics may also not eat regular and nutritious meals which can lead to a host of nutritional deficiencies.
  • Bowel conditions like Crohn’s disease, celiac disease and chronic diarrheal illnesses may affect the body’s ability to properly digest certain foods and absorb vitamin B12
  • Prolonged use of acid-suppressing drugs like proton pump inhibitors (PPIs) can also impair vitamin B12 absorption.

Vitamin B12 levels may vary slightly among individuals. Slightly low levels of vitamin B12 may not be considered as a deficiency. However, when the vitamin B12 levels are lower than the normal limit, changes in red blood cells can be seen and there are at least some symptoms then a vitamin B12 deficiency may be diagnosed.

Read more on vitamin B12 deficiency.

How To Spot Low Vitamin B12 Levels

Moderately low vitamin B12 levels may remain undetected for long periods of time. The symptoms in these instances may be mild and not immediately associated with a nutritional deficiency. Sometime other nutritional deficiencies may co-exist, such as iron deficiency which is the most common cause of anemia. However, as the deficiency worsens and persists for long periods of time then the effects become more extensive.

The symptoms of a vitamin B12 deficiency becomes more obvious but can still be misdiagnosed in meat eaters as a vitamin B12 deficiency may not be immediately suspected. The following signs and symptoms are only relevant to vitamin B12 deficiency in adolescents and adults. Deficiencies in young children can lead to growth problems and impact mental development which may result in additional signs and symptoms.

Tiredness and Weakness

Fatigue is a common sign in almost every instance of vitamin B12 deficiency. There may be varying levels of fatigue. Some people experience extreme tiredness which does not relieve significantly with sleep. Others may experience tiredness after even mild physical activity which was previously not a strain. There may also be weakness where a person find that they do not have the same strength or stamina as the previously did.

One of the reasons for this fatigue in vitamin B12 deficiency is the anemia that develops. This means that less oxygen can be carried and distributed through the bloodstream. However, fatigue and weakness are non-specific signs. It is present in many other diseases and disorders and should not be immediately attributed to low levels of vitamin B12 unless a deficiency has been confirmed with relevant blood tests.

Heart and Breathing Problems

As a result of the anemia, the body attempts to adapt to this lower oxygen-carrying capacity of the blood. This can give risk to heart and breathing symptoms. Firstly, the heart attempts to pump blood harder and faster in order to speed up the oxygenation of blood. The heart rate increases and may even exceed normal levels to surpass 100 beats per minute which is known as tachycardia.

The harder pumping of the heart may also result in palpitations. This is where a person can feel the heart pounding in the chest, which is normally not perceptible. Furthermore the lower oxygen levels triggers the brain. A person may perceive this as a shortness of breath or not being able to “get enough air”. As a result breathing rate may increase beyond normal limits (tachypnea).

Pale Skin and Smooth Red Tongue

Paleness (pallor) is another sign of anemia, which can arise with low levels of vitamin B12. One component of skin color is the redness of blood flowing in the superficial blood vessels. With anemia, this blood flow is affected not only due to the change of red blood cells but also as a result of narrowing of the superficial blood vessles. This causes paleness of the skin.

Another consequence of vitamin B12 deficiency anemia is inflammation of the tongue which is known as glossitis. It is usually a sign of severe anemia and may not be obvious in the early stages of vitamin B12 deficiency. The tongue becomes swollen, redder than normal and feels sore. It also appears smoother than normal as the papilla on the tongue which houses the taste buds are reduced. The sense of taste may also be impaired.

Numbness and Other Abnormal Sensations

The effects of vitamin B12 deficiency are not limited to the blood and circulation. It also affects the nerves, especially when low levels of vitamin B12 are persistent over long periods of time. This nerve involvement, also referred to as peripheral neuropathy, is more commonly associated with abnormal symptoms in the limbs (arms or legs).

Numbness is one of the common abnormal sensations that may occur along with tingling. These sensations are known as paresthesias. The numbness and tingling in the fingers and toes may worsen with cold exposure as blood flow to these areas are further restricted.

Read more on numbness and tingling in arms and legs.

Neurological and Psychological Disturbances

The neurological effects of vitamin B12 deficiency also affects the central nervous system (CNS).  This may be seen as disturbances with balance, coordination and even the sense of vision.  The can vary and ranges from depression to dementia. These are severe consequences of vitamin B12 deficiency which occurs with very low levels of vitamin B12 over a prolonged period of time.

More commonly the less severe neurological and psychological disturbances due to vitamin B12 deficiency may be noticed. People with this deficiency may report problems concentrating and with memory. There may also be difficulty understanding and even impairment in judgement. It is important to note that various dietary, lifestyle and other diseases or disorders may also causes these mental symptoms.

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