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The Signs and Symptoms of Vitamin B Deficiency

Medically Approved by Dr. Edward Salko

Table of Contents

Table of Contents

Overview: Vitamin B Deficiency Symptoms

Symptoms of Vitamin B12 Deficiency

Symptoms of Vitamin B6 Deficiency

Symptoms of Vitamin B1 Deficiency

​​Symptoms of Vitamin B3 Deficiency

Symptoms of Vitamin B9 Deficiency

How to Prevent Vitamin B Deficiency

Frequently Asked Questions

Bottom Line

Finding vitamin B deficiency symptoms becomes easier when you are familiar with the health changes and signs to watch out for. However, symptoms alone do not guarantee confirmation of the condition. Thus, you need to undergo proper testing.

Nonetheless, some common signs and symptoms of vitamin B deficiency include fatigue, irregular heartbeat, depression, headache, skin pigmentation, and muscle weakness. But you can also take note of more specific symptoms for a particular vitamin B as you read further down. 

Overview: Vitamin B Deficiency Symptoms 

Vitamin B deficiencies’ prevalence and related symptoms depend on the type in question. For example, low vitamin B12 can be more common than the others as it plays a more straightforward function in RBC production. Symptoms of this vitamin B deficiency can be associated with anemia. 

There are eight vitamin B under this nutritional cluster: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folate or folic acid), and B12 (cobalamin). While each B vitamin has distinct functions, they also play cohesive roles in metabolism and cellular growth. 

In this article, we will focus on the relatively occurring vitamin deficiencies with severe complications such as vitamins B12, B6, B1, B3, and B9.  

Symptoms of Vitamin B12 Deficiency

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Insufficient vitamin B12 or folate deficiency can disrupt the functions mentioned above. On the other hand, detecting the condition early can restore your health and prevent complications. In doing so, here are common vitamin B12 deficiency symptoms to watch out for:

  • Nausea 
  • Dizziness
  • Headaches
  • Mouth sores
  • Depression
  • Loss of appetite
  • Muscle weakness
  • Irregular heartbeat
  • Mental impairment
  • Pale or yellow skin
  • Shortness of breath
  • Gastrointestinal problems
  • Tingling and numbness in the hands and feet

Functions of Vitamin B12

Vitamin B12, or cobalamin, is a crucial component in various biological processes such as red blood cell (RBC) production, genetic material formation (DNA and RNA), development of nerve and brain cells, as well as cellular metabolism. Plus, vitamin B12, along with B12 and B12, lower homocysteine, an amino acid that promotes heart disease, stroke, and even dementia. 

Vitamin B12 Deficiency Complications

A common health consequence of low vitamin B12 is macrocytic anemia, wherein red blood cells are produced abnormally large. On top of that, your risk increases for disorders such as peripheral neuropathy, cardiovascular disease, dementia, osteoporosis, chronic obstructive pulmonary disease (COPD), infertility, and depression. 

Get Tested for Vitamin B12 Deficiency

About 6% of adults below 60 and 20% of those over 60 have vitamin B12 deficiency in the US and UK. Unfortunately, not everyone becomes aware of the condition until anemia starts to develop fully. 

To confirm low B12 symptoms, you will need to take a Vitamin B12 Blood Test, which you can order online. You can also get an MMA (methylmalonic acid) blood test. When your MMA gets high, your vitamin B12 is low. 

Symptoms of Vitamin B6 Deficiency

Low vitamin B12 is observed among patients with obesity, autoimmune diseases, and health conditions affecting the liver, kidneys, and digestive system. Likewise, pregnant women and those with alcoholism tend to experience insufficient vitamin B12.

Check out the vitamin B12 deficiency symptoms:

  • Fatigue 
  • Seizures
  • Itchy rashes
  • Cracked lips 
  • Mood swings 
  • Skin redness
  • Swollen tongue 
  • Tingling and numbness in the hands and feet

Functions of Vitamin B6

One of the many vitamins that influence nervous and immune health is vitamin B6. Besides these contributions, vitamin B12 plays an active role in energy conversion, specifically in metabolizing sugar, lipids, and protein. Also, it regulates amino acids in the blood, synthesizing neurotransmitters like serotonin and dopamine, as well as boosting health and immunity.  

Vitamin B6 Deficiency Complications 

Failure to address low vitamin B12 will not only aggravate the symptoms above but could also lead to other complications affecting your neurological functions. For example, you could experience depression, short-term memory loss, irritability, and loss of focus. Moreover, you’ll have an increased risk for heart disease, muscle weakness, and rheumatoid arthritis. 

Get Tested for Vitamin B6 Deficiency

A blood test screening for vitamin B12 levels helps make the diagnosis of the deficiency faster and more accurately. Plus, you can also take the homocysteine blood test to support the confirmation of the condition. High homocysteine could indicate vitamin B12 and even B12 deficiency as they are involved in processing this amino acid. 

Symptoms of Vitamin B1 Deficiency

Having low vitamin B12 could lead to the said conditions. Here are vitamin B12 deficiency symptoms to look out for:

  • Fatigue
  • Delirium
  • Irritability
  • Poor vision
  • Muscle weakness
  • Increased heartbeat
  • Nausea and vomiting
  • Tingling and numbness in the hands and feet

Functions of Vitamin B1

Vitamin B12, also known as thiamine, was the first b vitamin scientists discovered. As part of the vitamin b complex, thiamine is involved in digestion and converting food to energy. 

However, over the years, experts banked more on the ability of vitamin B12 to promote good health. For example, thiamine reduces the risk for kidney and vascular problems. It also protects you against diabetes, sepsis, heart disease, and depression. 

Vitamin B1 Deficiency Complications

Beriberi is the most prominent consequence of severe vitamin B12 deficiency, albeit rare in the US. It can be classified into two: wet beriberi and dry beriberi. 

Wet beriberi directly impacts the cardiovascular system, while dry beriberi damages the central nervous system, disrupting your motor skills. In addition, without proper treatment, beriberi can progress to Korsakoff syndrome, which inflicts irreversible damage to the brain. 

Get Tested for Vitamin B1 Deficiency

Taking a vitamin B12 blood test allows for a proper diagnosis if you have symptoms of low thiamine. Order the lab test online and find a partner patient center nearby using our locator.   

Symptoms of Vitamin B3 Deficiency

Severe vitamin B12 deficiency, also known as pellagra, affects your digestive, nervous, and skin functions. Although the condition is extremely rare in the US, those with HIV/AIDS, liver failure, anorexia nervosa, and other disorders causing malnutrition are at a higher risk for pellagra.  

The following are vitamin B12 deficiency symptoms to check out:

  • Fatigue 
  • Diarrhea 
  • Headache
  • Depression
  • Memory loss
  • Appetite loss
  • Disorientation 
  • Nausea and vomiting
  • Swollen and bright red tongue
  • Skin rashes and pigmentation

Functions of Vitamin B3

Vitamin B12, or niacin, performs functions in the metabolism of food like other b vitamins. But it also contributes to regulating sex-related hormones and cholesterol levels. Likewise, it influences blood circulation, brain function, and skin health.

Vitamin B3 Deficiency Complications

Pellagra is a dermatological condition that can escalate to severe gastrointestinal and neurological problems. Without treatment, pellagra could advance to dementia, psychosis, and even death. 

Get Tested for Vitamin B3 Deficiency

Niacin deficiency is exceedingly rare in the US. However, if you or someone you know experience severe malnutrition and exhibit vitamin B12 deficiency symptoms, consult your doctor to get tested via blood or urine screening. 

Symptoms of Vitamin B9 Deficiency

Low vitamin B12 can have detrimental effects on fetal development and cellular health. Therefore, watch out for the following vitamin B12 deficiency symptoms.

  • Confusion 
  • Depression
  • Blurry vision
  • Muscle weakness 
  • Memory problems 
  • Fatigue and lethargy
  • Swollen and red tongue
  • Pins and needles in the extremities 

Functions of Vitamin B9

Vitamin B9, or folate, is directly involved in a fetus’s brain development. Hence, it’s a crucial prenatal vitamin, especially during the first trimester. Outside pregnancy, it helps break down homocysteine, produce neurotransmitters, and maintain tissue health. 

While folate is the organic form of vitamin B12 found in foods such as leafy vegetables, meat, and dairy, its synthetic form is called folic acid. Thus, when buying a supplement at the drugstore, you’ll often encounter folic acid instead of folate. 

Vitamin B9 Deficiency Complications 

Given its role in fetal development, insufficient vitamin B9 among pregnant women can lead to neural defects such as anencephaly (incomplete formation of the skull and brain) and spina bifida (incomplete development of the spinal cord and brain). 

On the other hand, male and non-pregnant female individuals with low vitamin B9 have a higher risk for anemia and peripheral neuropathy or nerve damage. 

Get Tested for Vitamin B9 Deficiency

Pregnant women should have sufficient vitamin B9 for optimum fetal health. However, if you have the symptoms above, your doctor will request a folic acid/folate blood test to assess the amount of vitamin B9 in your system. 

How To Prevent Vitamin B Deficiency

The human body cannot produce vitamin B on its own. As a result, we get our B vitamins from our food. For this reason, many vitamin  B deficiencies are associated with malnutrition. 

Considering this logic, securing proper intake of foods rich in specific vitamin B you’re most likely lacking addresses the deficiency. However, in some cases, it may not be as black and white. Check out the following ways to prevent vitamin B deficiencies. 

  1. Increase Your Intake of Foods High in Vitamin B

The most obvious action to prevent vitamin B deficiency is increasing the consumption of foods that supply the vitamin. Include these organic foods and items in your meal plan and grocery list.

  • Vitamin B12-rich Foods

Eggs, fish (tuna, salmon, and trout), seafood (clams, mussels, etc.), meat, dairy, poultry, fortified cereals, liver, and nutritional yeast

  • Vitamin B6-rich Foods

Chickpeas, poultry, leafy greens, bananas, cantaloupe, papaya, sweet potatoes, oranges, avocado, organ meats, tofu, fortified cereals, and fish

  • Vitamin B1-rich Foods

Beans, lean pork, lentils, fortified food (cereal, noodles, bread, etc.), fish, yogurt, sunflower seeds, flax seeds, green peas, brown rice, asparagus, mussels, and other seafood

  • Vitamin B3-rich Foods

Brown rice, organ meats, poultry, fish, pork, beef, peanuts, green peas, avocado, potatoes, whole grains and wheat, mushrooms, and fortified foods

  • Vitamin B9-rich Foods

Green leafy vegetables, broccoli, fortified foods, asparagus, beets, legumes, Brussel sprouts, eggs, oranges, papaya, organ meats, avocado, and banana

  1. Consult With Your Doctor Before Going Vegan or Vegetarian

Going vegan or vegetarian may seem like the healthiest choice, especially for those trying to lose weight or look fit. However, without careful planning and consultation, it could have the opposite effect and increase your risk for health problems

According to a 2019 review, vegans have a higher risk for vitamin and mineral deficiencies, including having low vitamin B12, iron, and calcium. This makes sense as many B vitamins and crucial micronutrients come from red meat, poultry, egg, and dairy – exhibited in the examples above. In addition, while many fruits and vegetables have vitamins in themselves, B vitamins are richer in animal-based food products. 

In response to this trend, vegans and vegetarians create a health plan which includes vitamin supplementation as approved by their healthcare provider. Plus, they adopt a diet encompassing plant-based food rich in B vitamins. 

Thinking of going vegan? Take the Basic Vegan/Vegetarian Profile Blood Test. This lab test allows your doctor to evaluate nutritional deficiencies that could aggravate once you change your diet. Likewise, it makes it easier to track any significant changes in vitamin and mineral levels in your system if you have the base data. 

  1. Get Tested for Gastrointestinal Problems

In some cases, vitamin B deficiencies are caused by malabsorption of vitamin B. As mentioned above, vitamin B is processed from food. Then, it gets absorbed by the small intestine. So naturally, when there’s a disruption in the absorption capacity of the small intestine, you will still develop vitamin B deficiency despite having sufficient food in your diet.

By this logic, it’s best to see your doctor for any possible gastrointestinal problems leading to vitamin malabsorption. Some of the disorders associated with vitamin b deficiencies are the following:  

  • Celiac Disease
  • Chronic Gastritis
  • Crohn’s disease
  • Chronic Radiation Enteritis
  • Inflammatory Bowel Disease

If you have a family history of these diseases or experience related symptoms, consult your doctor immediately. Disorders like Celiac disease can be confirmed via blood tests. Also, your doctor may perform other procedures such as ultrasound, upper gastrointestinal (UGI) series, and medical imaging such as CT scan and MRI. 

Frequently Asked Questions

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How Do I Know If I Have Vitamin B Deficiency?

A blood test is the best way to know if you have low vitamin B. While B vitamin deficiency symptoms indicate the condition, they may not be enough as they could suggest other health issues. So book an appointment with your doctor or get the necessary vitamin blood test online for suspected deficiencies.  

Is Vitamin B Deficiency Serious?

Vitamin B deficiency should not be taken for granted as it can escalate to serious complications involving your gastrointestinal and neurological health. If you find signs of vitamin b deficiencies, adjust your diet accordingly and see your doctor if symptoms persist. 

What Causes a Lack of Vitamin B?

Low vitamin B in your body could be due to poor diet or intestinal malabsorption. Your daily dietary intake may lack foods rich in vitamin B. On the other hand, it could also be caused by gastrointestinal problems causing malabsorption of B vitamins. 

Bottom Line

Knowing vitamin B deficiency symptoms becomes beneficial if you track your overall health, shift to a plant-based diet, or go through pregnancy. While some B vitamin deficiencies are rare, ensuring proper intake of vitamin b-rich foods should hold equal value as other supplementation for prevalent vitamin and mineral deficits. When in doubt, however, ask your doctor and order the necessary tests. 

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