Vitamin B Deficiency

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B vitamins are a group of 8 essential vitamins which have an important role in keeping your body healthy. Find out about vitamin B deficiencies, here.

vitamin b foodsB vitamins are a group of 8 essential vitamins that have an important role in keeping your body healthy, maintaining cell health and helping to convert food into energy. As there’s so many vitamins in this category, if you suffer from a vitamin B deficiency, the signs can vary greatly depending on which B vitamin you’re lacking in particular.
In this guide we look at all the different B vitamins and how you can recognise the signs of a deficiency.

Who’s most at risk for vitamin B deficiency?

Elderly individuals and pregnant women are two of the most at-risk categories as they need more B vitamins in their diet. Additionally, those that suffer from Crohn’s disease, celiac disease, HIV and alcohol abusers are all at a greater risk as these conditions can impact the body’s ability to absorb B vitamins.

Vitamin B12 deficiency

Also known as cyanocobalamin, vitamin B12 helps to regulate the nervous system and also assists with the formation of red blood cells and growth. A deficiency in vitamin B12 can cause megaloblastic anaemia where the bone marrow produces large, abnormally shaped red blood cells that don’t work correctly. It can also result in certain psychological conditions such as: dementia, paranoia, depression and behavioural changes.

Signs of vitamin B12 deficiency

  • woman suffering from fatigueFatigue
  • Weakness
  • Lack of appetite
  • Constipation
  • Weight loss
  • Numbness or tingling in the hands and feet
  • Balance issues
  • Problems with memory and confusion
  • Sore mouth and/or tongue

Vitamin B12 is found in lots of meats and dairy products so as such, vegans and vegetarians are at a greater risk of this vitamin B deficiency and may need to take a dietary supplement.

Vitamin B6 deficiency

Pyridoxine (vitamin B6) helps to turn food into energy and also assists with fighting infections. Vitamin B6 deficiency alone is generally quite uncommon and is usually an indicator of another vitamin B deficiency such as B12 or folic acid. Those that suffer with end-stage renal disease, chronic renal insufficiency and kidney diseases are more at risk, alongside those with celiac disease, Crohn’s disease, ulcerative colitis and homocystinuria. Taking antiepileptic medications over time may lead to a vitamin B6 deficiency too.

Signs of vitamin B6 deficiency

  • Depression
  • Nausea
  • Anaemia
  • Confusion
  • Infections
  • Skin rashes
  • Swollen tongue
  • Scaling lips with cracks at the corners of the mouth

Organ meats, poultry, fish, starchy vegetables (potatoes, etc) and non-citrus fruits are foods all high in vitamin B6 and you should get all you need from your diet.

Vitamin B1 deficiency

Thiamine (vitamin B1) helps to convert food into energy and has several neurological benefits. It’s very rare to develop a vitamin B1 deficiency, but alcohol abusers can experience it as this can inhibit absorption.

Signs of vitamin B1 deficiency

  • Nausea
  • Lack of appetite
  • Fatigue
  • Concentration issues
  • Weakness
  • Tiredness
  • Memory issues
  • Leg and/or foot cramping
  • Burning pain in feet
  • Headache
  • Constipation
  • Cramping

Vitamin B1 is present in many foods such as milk and whole-grains which are often fortified with it.

Vitamin B2 deficiency

Vitamin B2, known as riboflavin, helps to convert food into energy and maintain eyesight. A deficiency is very rare and usually other vitamin B deficiencies will be present at the same time. However, those that suffer from thyroid hormone insufficiency are particularly at risk.

Signs of vitamin B2 deficiency

  • Skin disorders
  • Excess blood
  • Swelling of the mouth and throat
  • Lesions at the corners of the mouth
  • Swollen and/or cracked lips
  • Hair loss
  • Reproductive issues
  • Sore throat
  • Itchy and/or red eyes
  • Liver and/or nervous system degeneration

Like vitamin B1, B2 is present in many foods and milk and cereals tend to be fortified with it.

Vitamin B3 deficiency

Like the other B vitamins, niacin (vitamin B3) converts food to energy, assists with digestion and normal appetite and also plays a role in cell development. Niacin deficiency can be linked to genetic disorders, malabsorptive conditions and certain medications. Extreme deficiency in this B vitamin can result in a condition called pellagra.

Signs of vitamin B3 deficiency

  • Red tongue
  • Rough skin which may redden or brown in the sun
  • Vomiting
  • Diarrhoea
  • Constipation
  • Fatigue
  • Behavioural changes
  • Hallucinations

Vitamin B3 is found in many foods including meats, nuts, legumes and grains, as well as fortified breads and cereals.

Vitamin B9 deficiency

Folate (vitamin B9) deficiency is more likely to occur in pregnant women, alcohol abusers, those that take certain medications such as antiepileptic drugs and proton pump inhibitors and individuals with gastrointestinal disorders like coeliac and Crohn’s disease. In severe cases it can lead to folate deficiency anaemia, an increased risk of heart disease and birth defects such as neural tube defects (NTD) like spina bifida and anencephaly.

Signs of vitamin B9 deficiency

  • Tiredness
  • Weakness
  • Shortness of breath
  • Heart palpitations
  • Concentration issues

Many foods contain vitamin B9 including leafy greens, beans, peas, lentils, eggs, shellfish, beetroot, oranges and wholegrains. You may also encounter the synthetic form of vitamin B9, folic acid which gets added to foods.

Vitamin B5 deficiency

Vitamin B5 (pantothenic acid) has a role to play in the creation of red blood cells and luckily, deficiency is very rare. It tends to only occur in malnourished people and usually other vitamin B deficiencies will be present too.

Signs of vitamin B5 deficiency

  • Headaches
  • Fatigue
  • Irritability
  • Muscle coordination issues
  • Gastrointestinal issues

Meats, fish, grains, dairy, legumes and vegetables are all great food sources of vitamin B5.

Vitamin B7 deficiency

Biotin (vitamin B7) deficiency is very rare as it’s produced by bacteria in the intestine and is widely available in food. Interestingly, biotin deficiency can be caused by eating too many raw egg whites (more than 2 a day over the course of several months) as it contains avidin which binds vitamin B7. Additionally, a deficiency in this B vitamin can be caused by a genetic deficiency, multiple carboxylase deficiency and holocarboxylase synthetase deficiency.

Signs of vitamin B7 deficiency

  • Seborrheic dermatitis
  • Red rashes
  • Brittle hair and/or hair loss
  • Conjunctivitis
  • Difficulty co-ordinating body movement
  • Lethargy
  • Loss of appetite
  • Depression
  • Hallucinations
  • Reduced immune function

Organ meats, eggs, fish, seeds, nuts and vegetables such as sweet potatoes are all excellent sources of biotin.

Treating vitamin B deficiencies

Vitamin B tabletsThe treatment for any vitamin B deficiencies will depend on the related symptoms. If you’re experiencing a less severe case, your doctor will likely recommend supplements, alongside an increased intake of B vitamin rich foods. If you’re concerned about your health or believe you may be deficient in B vitamins, consult your doctor as soon as possible.

That’s our guide to vitamin B deficiencies! Want to find out more about these clever little vitamins? Learn exactly what vitamin B is and what it does in our guide.


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