If you’re deficient in certain B vitamins, then you might feel a range of symptoms.

Some people feel muscle pain and weakness due to low B vitamin levels, for example. Others experience irregular heart rhythms, depression, confusion, or other issues linked to B vitamin deficiency.

There are 8 vitamin B nutrients. Depending on your deficiency, your symptoms may vary. Keep reading to discover how B vitamin deficiency works.

What Are B Vitamins?

B vitamins are a group of 8 nutrients that play various roles throughout the body.

Overall, B vitamins play a crucial role in energy production. They support health at the cellular level, keeping you energized.

However, many people are deficient in B vitamins even though they have good energy levels. Because there are 8 different B vitamins, deficiencies work in different ways.

Who’s at Risk of B Vitamin Deficiency?

Certain groups have a higher risk of B vitamin deficiency, including:

  • Older adults
  • Pregnant women
  • People with Crohn’s disease or celiac disease, which could inhibit the absorption of nutrients
  • People with HIV
  • Alcoholics
  • Vegans or vegetarians following a poorly-planned diet

Depending on your condition, your doctor may recommend taking a B vitamin supplement or adjusting your diet to get more B vitamins.

Vitamin B1 and B2 Deficiency

The first two B vitamins (by numerical order) are:

  • Vitamin B1 (thiamine)
  • Vitamin B2 (riboflavin)

Your body uses these B vitamins to convert food into energy. Vitamin B1 is particularly important for brain energy, while vitamin B2 supports good eyesight.

Signs of vitamin B1 and B2 deficiency include:

  • Confusion
  • Mental fog
  • Cracks along the sides of your mouth

Both vitamin B1 and B2 deficiency are rare in developed countries, including the United States. However, alcoholics have a particularly high risk of this deficiency.

To add more vitamin B1 and B2 to your diet, take whole grains, fortified bread and cereal, eggs, organ meats, lean meats, low-fat milk, nuts and seeds, legumes, and green vegetables.

Vitamin B3 Deficiency

Vitamin B3, or niacin, converts food into energy. Like other B vitamins, it plays a crucial role in supporting energy at the cellular level.

Vitamin B3 also helps with appetite regulation and overall cell development.

Signs of vitamin B3 deficiency include:

  • Vomiting
  • Constipation or diarrhea
  • Fatigue
  • A bright red tongue

Vitamin B3 deficiency is rare in developed countries, including the United States. In more serious cases, vitamin B3 deficiency can lead to suicidal behavior, hallucinations, aggression, and paranoia.

The best foods for vitamin B3 include fortified breads and cereals, nuts, legumes, grains, and meat.

Vitamin B5 Deficiency

Pantothenic acid, or vitamin B5, is rare in the United States because there are plenty of food sources of vitamin B5. However, you may experience symptoms like numbness in the hands and feet, headache, irritability, restlessness, poor sleep, and a lack of appetite because of vitamin B5 deficiency.

Signs of vitamin B5 deficiency include:

  • Headache
  • Numbness or a burning sensation in your hands and feet
  • Irritability
  • Restlessness and poor sleep
  • Low appetite

The best food sources of vitamin B5 include tuna, chicken, avocados, beef liver, certain types of mushrooms, sunflower seeds, and fortified breakfast cereals.

Vitamin B6 Deficiency

Vitamin B6, or pyridoxine, converts food into energy. It also supports immunity, helping your body fight infections. Vitamin B6 deficiency is more common than vitamin B1, B2, and B3 deficiencies, although it’s still uncommon in the developed world.

Vitamin B6 deficiency can cause:

  • Depression and confusion
  • Nausea
  • Anemia (low red blood cell count)
  • Infections or a weakened immune system
  • Skin rashes and dermatitis

Some of the best foods for vitamin B6 include meats (particularly poultry, fish, and organ meats), potatoes, starchy vegetables, and fruits.

Vitamin B7 Deficiency

Biotin, or vitamin B7, is a valuable nutritional supplement for supporting hair, skin, and nail health. Although evidence is mixed on whether taking a vitamin B7 supplement helps, vitamin B7 deficiency can lead to issues with your hair, nails, and skin.

Symptoms of biotin (vitamin B7) deficiency include:

  • Thinning hair
  • Rashes or scaling on your skin, particularly around your face, yes, nose, and mouth
  • Brittle nails
  • Depression
  • Fatigue

The best food sources of vitamin B7 include organ meats, salmon, pork, eggs, sunflower seeds, and beef.

Vitamin B9 Deficiency

Folate, also known as vitamin B9, is available in fortified foods and certain supplements. Alternatively, you can get folate from leafy greens and vegetables. The natural form of vitamin B9 is called folate, while the version you get in certain foods is called folic acid.

Your body needs vitamin B9 for critical DNA functions. It also metabolizes vitamins and amino acids while promoting cell division.

Signs of vitamin B9 deficiency include:

  • Weakness
  • Headache
  • Heart palpitations
  • Changes to your skin, hair, and nails, including sores around the mouth
  • Irritability

To increase vitamin B9 intake, add orange juice, eggs, beans, nuts, avocado, beef liver, or leafy green vegetables to your diet. These foods are rich with vitamin B9.

Vitamin B12 Deficiency

Vitamin B12 deficiency is one of the most common B vitamin deficiencies. Vitamin B12, or cobalamin, supports the nervous system, cellular energy, and overall growth.

If you are deficient in vitamin B12, you could experience dementia, paranoia, depression, and other serious neurological conditions. When left untreated, vitamin B12 deficiency can lead to irreversible neurological damage.

Signs of vitamin B12 deficiency include:

  • Weakness, tiredness, and fatigue
  • Constipation
  • Weight loss
  • Numbness or tingling in the extremities
  • Confusion and poor memory

Others experience soreness around the mouth or tongue because of vitamin B12 deficiency. Some have a loss of appetite and balance problems because of vitamin B12 deficiency.

Vegans and vegetarians are more likely to experience vitamin B12 deficiency because there are no good plant sources of vitamin B12. The best food sources include beef liver, eggs, milk, cheese, and certain fortified foods. If you’re not taking these foods and not taking a vitamin B12 supplement, then you could be deficient.

How to Test for B Vitamin Deficiencies

Any nutrient deficiency test or panel test can check for B vitamin deficiencies.

You can check for B vitamin deficiencies at home (using a home testing kit) or at a lab.

Alternatively, many people take a Science Based Nutrition blood test.

We specialize in Science Based Nutrition tests. You can compare your bloodwork to an optimal health range instead of the last 100 to 200 people who visited a lab.

Order your B vitamin deficiency testing kit today to get crucial insight into your health.