Vitamin B12 Deficiency Symptoms

Vitamin B12 Deficiency Symptoms

How Do You Know If Your B12 Is Low? 

You will feel restless, weak, and tired when your B12 is low. You will experience issues with your memory and thinking capabilities soon after the B12 deficiency. One of the other noticeable effects of B12 deficiency is digestive problems.

Vitamin B12, also known by the scientific term cobalamin, is a crucial water-soluble vitamin in your body. Vitamin B12 plays a vital role in producing DNA and red blood cells in your body, in addition to enhancing the proper functioning of your overall nervous system.

The lack of red blood cells in your body will provide insufficient oxygen supply to the gut, making you feel sick. You may feel nausea and vomit and, in some cases, experience diarrhea. The feeling of having low B12 is directly related to the symptoms of B12 deficiency. So, when in doubt, check for the signs of B12 deficiency.

Vitamin B12 can be commonly derived and consumed from animal foods like fish, meats, eggs, poultry, and dairy products. Moreover, various bread and plant-based milk products are fortified with B12, which can also be a source of this vitamin.

Unfortunately, there has been reported a significant increase in B12 deficiency cases, especially in the elderly. If you don’t get enough B12 from your regular diet, or if your body’s unable to absorb enough B12 from food, you can carry the risk of having B12 deficiency.

The risk of having B12 deficiency is especially common in the elderly, people taking the drug metformin for diabetes, people who’ve had surgery to remove the part of the bowel that absorbs B12, and people under a strict vegan diet plan.

At times, people confuse the symptoms of B12 deficiency for a folate deficiency. Your folate levels may drop due to B12 deficiency, and if you simply correct the low folate levels the deficiency symptoms may be masked, but you won’t solve the underlying problems and effects for the long term.

This is why this article guide will show you all the signs and symptoms of B12 deficiency, along with a brief explanation of why it’s considered a low B12 symptom for your easy understanding.

So, let’s begin!

1. Jaundiced skin - A slight yellow tinge on the skin

People who have low levels of B12 often have one of the symptoms of jaundice, which is pale skin. You will have a slightly yellow tinge on the skin and the white portion of your eyes. Jaundice happens as a result of lack or insufficient production of red blood cells caused due to the low B12 level.

The levels of B12 in your body play a vital role in the overall DNA production, which ultimately determines the production of red blood cells. Without sufficient DNA production, your cells will find no instructions to build up, divide, and function in the body.

B12 deficiency can cause havoc to your health as you may incur megaloblastic anemia, a type of anemia where the human body produces large and fragile red blood cells within the bone marrow.

These red blood cells become too large to pass through the bone marrow and join the overall circulation. Thus, your body lacks sufficient red blood cells circulating the body, resulting in the skin with a pale yellowish color appearance.

The fragile state of the red blood cells in the bone marrow indicates their breakdown, resulting in excessive bilirubin production.

Bilirubin is a light red or brownish substance produced by your liver while breaking down old blood cells. The excessive amount of bilirubin in the body results in a yellow tinge in the skin and eyes.

If you notice that your skin appears pale or jaundiced, visit a doctor to confirm whether you’re low on B12.

2. Feeling tired and weak

The feelings of fatigue and weakness have been reported as the two most common symptoms of B12 deficiency. Weakness usually happens due to the body’s inability to absorb enough B12 for producing red blood cells, which has the role of transporting oxygen to the entire body. Insufficient red blood cells result in reduced capacity to transport oxygen to the vital body cells, giving you a weak, tired, and listless feeling.

Autoimmune conditions such as pernicious anemia are mainly a result of low cobalamin levels. People with this type of anemia lose the ability to produce enough of a protein named intrinsic factor. This protein is crucial for keeping you protected from the B12 deficiency, as it binds with vitamin B12 and holds it in your gut for absorption.

When your body is low in vitamin B12, it produces deficient levels of red blood cells, causing insufficient oxygen supply in your body, resulting in weakness and fatigue.

3. Nerve problems - Feeling of pricking sensations described as pins and needles

Nerve damage has reportedly become one of the most severe effects of having B12 deficiency for a prolonged period. Nerve damage happens over time as vitamin B12 plays a crucial role in contributing to the metabolic pathways that produce the fatty substance called myelin. Myelin helps cover the nerves to act as a protective insulating barrier. The damaged myelin causes tingling and other neurological disorders.

If you have a low B12 level, there will be a difference in myelin production, resulting in improper functioning of your nervous system. You will experience paresthesia, which is the sensation of “pins and needles” similar to the prickling sensation in your body.

Moreover, the neurological signs of B12 deficiency usually happen with the effects of anemia. However, recent studies show that about 28% of people have incurred neurological symptoms due to B12 deficiency without any traces of having anemia.

The sensations of pins and needles are typical symptoms that can happen due to several causes, so this sensation or feeling cannot be the only factor to indicate B12 deficiency.

To summarize, B12 helps in myelin production in the body. This myelin is responsible for insulating the nerves and regulating the functioning of the nervous system. The sign and symptom to understand potential nerve damage due to B12 deficiency is a sensation of pins and needles.

4. Changes in your mobility - Affecting your balance and coordination

The effects of having B12 deficiency in your nervous system can be dramatic.

If left undiagnosed, the nerve damage can result in causing changes in the way you walk and move. You might feel more prone to falling with the extended effect on your balance and coordination. This symptom is commonly found among the elderly, aged 60 or more, who have undiagnosed B12 deficiency.

If any young individual has a severe, undiagnosed vitamin B12 deficiency, the chances are pretty high for mobility problems. However, diagnosing and treating a B12 deficiency improves mobility in any age group.

If the B12 deficiency is left untreated for several years, it damages your mobility by affecting your balance and coordination and changing your way of walking and moving.

5. Mouth Ulcers and Glossitis

According to a study, long straight lesions on a swollen, inflamed tongue could be the early signs of vitamin B12 deficiency.

Glossitis is the most commonly used medical term for an inflamed tongue. If you have glossitis, you will notice changes in the shape and color of your tongue. Your entire tongue will become red, painful, and swollen. The tiny bumps present on your tongue, consisting of your taste buds, get stretched out and disappear, making your tongue look smooth.

Apart from feeling the pain, you will notice a change in speaking and eating if you have glossitis.

There are a few other oral symptoms that come up with B12 deficiency. You may also experience pins and needles in the tongue, mouth ulcers, or getting a burning and itching feeling in the mouth.

If you have a red and swollen tongue, you can consider it an early sign of B12 deficiency. 

6. Feeling dizzy and experiencing breathlessness

If your B12 deficiency makes you anemic, you will experience shortness of breath and dizziness, especially during exertion. Dizziness happens as your body lacks enough red blood cells, which it needs to supply oxygen to various body cells.

However, these symptoms can occur due to several causes, so it’s best to speak or consult a doctor and investigate the condition if you notice uncertain shortness of breath.

7. Having impaired or disturbed vision

Blurred or disturbed vision is another common symptom of B12 deficiency. Blurred vision happens when the undiagnosed vitamin B12 deficiency causes severe damage on the optic nerve that traces back to your eyes.

The nervous system damage due to B12 deficiency can disturb the traveling of nerve impulse signals from your eyes to the brain, resulting in impaired vision. In medical terms, the condition is named optic neuropathy. Even if it’s a dire condition, research says that optic neuropathy is reversible with the help of vitamin B12 supplements.

8. Mood alterations

There have been consistent reports from people saying they feel mood alterations due to B12 deficiency. However, you must remember that mood alterations and mental health conditions like dementia or depression can happen due to various reasons. So, the impact of supplementing with B12 to relieve cognitive disorders is only helpful if you have a B12 deficiency.

Studies have shown that low levels of B12 are associated with mood alterations and brain disorders such as dementia and depression.

This association between B12 deficiency and mood alteration has been supported with the explanation “homocysteine hypothesis of depression”. The report suggests that the high levels of homocysteine caused due to low B12 levels can impact your brain tissues with damage, disrupt the signals to and from your brain, and ultimately lead to mood changes.

A few crucial studies suggest that supplementing with vitamin B12 can reverse the symptoms of low B12, like dementia in certain people.

It’s always helpful to take a supplement to raise your B12 levels. However, taking supplements is in no way close to being an alternative for other proven therapies for conditions like dementia or depression.

9. High body temperature

Having a high temperature is an occasional and infrequent symptom of having B12 deficiency. The exact reason for this symptom is still unclear.

Still, a few doctors have reported successfully administering B12 and folate injections to treat fever (or pyrexia).


So, the feeling of having low vitamin B12 in your body correlates with the signs and symptoms of B12 deficiency.

You will know that you have low B12 if you experience the following signs:

  • Jaundiced skin with a slight yellowish tinge

  • Feeling weakness and fatigue

  • Pins and needles sensations due to nerve damage

  • Mobility problems

  • Mouth ulcers and glossitis

  • Impaired vision

  • Breathlessness, dizziness

  • Mood changes

  • High body temperature

In case you suspect low B12, you should see a doctor for a blood test. You can also choose to boost your B12 levels with the best supplement products like Why Not Natural B12 liquid Supplement. Taking the vitamins sublingually ensures the best absorption rate and faster relief from your deficiency symptoms.

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