B vitamins are responsible for making red blood cells, which carry oxygen throughout your body. They also assist in metabolism and are important for good brain function. B vitamins are found in meat (including liver), poultry, fish, soybeans, milk, eggs, whole grains, and enriched bread and cereals.

B vitamins are water-soluble.

Firstly, water-soluble vitamins travel through the bloodstream. Whatever you don’t use is expelled when you urinate. However, it’s important to maintain a good balance rather than potentially overdosing yourself or your child. For more information on water-soluble vitamins, fat-soluble vitamins, or minerals, visit our Vitamins and Deficiencies blog.

B vitamins include an array of different compounds that help to regulate the body’s processes. They are each important for normal bodily function, though the ones that people tend to be most deficient in are vitamins B12, B6, and B1, and folic acid. Other B vitamins include B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B7 (biotin), PABA, choline, and inositol.

While high levels of B vitamins do not typically endanger us because they are water-soluble, an overdose of vitamins B3, B6, and folate can cause some issues. See symptoms of B3, B6, and folate overdoses below.

Moreover, for those interested in the minimum RDAs (Recommended Dietary Allowances) for the B vitamins, refer to this National Academies chart.

B Vitamins

Vitamin B12 

Vitamin B12 is important for synthesizing DNA, red blood cells, nerves and carrying out important body functions. We cannot create B12 in our bodies and we get B12 from the foods we eat. B12 is found in meat, eggs, poultry, dairy, and other animal products, so vegetarians and vegans typically supplement B12 or eat foods fortified with B12, like bread, cereals, or other grains. Additionally, people with certain food absorption conditions like celiac disease or Crohn’s disease may have B12 deficiencies.

Symptoms of Vitamin B12 Deficiency

  • Numbness or tingling in hands, legs, and/or feet
  • Weakness
  • Fatigue
  • Balance problems and difficulty walking
  • Anemia
  • Swollen tongue
  • Jaundice (yellow skin)
  • Cognitive difficulties or memory loss
  • Developmental delays and/or failure to thrive

Vitamin B6 (Pyridoxine)

Pyridoxine helps our bodies use and store energy from the food we eat.  It also forms hemoglobin, the component of red blood cells that carries oxygen throughout our bodies. Vitamin B6 is found in pork, poultry, fish, eggs, milk, chickpeas, whole grains, vegetables, peanuts, and some fortified cereals.

Symptoms of B6 deficiency include anemia, dermatitis, depression, confusion, weakened immune function, irritability, and abnormally acute hearing in infants.

It is possible to overdose on vitamin B6. Taking more than 200mg per day for an extended period of time can cause peripheral neuropathy, a loss of feeling in arms and legs. This condition will go away once you have stopped taking B6 supplementation. However, if taken for many months, the effects can be permanent.

Vitamin B1 (Thiamine)

Thiamine helps us to metabolize food and maintain a healthy nervous system.  Sources of thiamine include peas, liver, fruit, whole grains, eggs, beans, and certain fortified cereals. Symptoms of thiamine deficiency include weight loss, anemia, confusion, short term memory loss, muscle weakness, and cardiovascular issues.

Folic acid

Folic acid, or folate, helps form red blood cells and reduces the risk of neural tube defects, like spina bifida, in fetuses.  This is why it is particularly important for pregnant women to get enough folic acid in their diets.  Pregnant women should take 400 mcg of folic acid daily until the 12-week mark. Folic acid is found in broccoli, Brussels sprouts, spinach, asparagus, peas, chickpeas, rice, enriched spaghetti, and some fortified cereals.

An overdose of folic acid (more than 1mg) can hide symptoms of a B12 deficiency. A B12 deficiency that goes unnoticed can damage the nervous system. This is more common in older people due to problems absorbing vitamin B12.

Vitamin B2 (Riboflavin)

Firstly, riboflavin helps us to metabolize food and keeps skin, eyes, and nervous tissue healthy. We know that vitamin B2 functions as an antioxidant in that this vitamin protects against free radicals in our bodies. Free radicals, like fried foods or cigarette smoke, are substances that can damage our cells, and in some cases, play a role in cancer development. Furthermore, riboflavin exists naturally in milk, eggs, rice, and certain fortified cereals. Deficiency in riboflavin causes eye fatigue, among other symptoms.

Vitamin B3 (Niacin)

Niacin helps us to metabolize our food and keeps our nervous system and skin healthy. Higher levels of this vitamin can improve cardiovascular function by lowering LDL (bad) cholesterol levels.  Sources of niacin include meat, fish, eggs, milk, and wheat flour.  Niacin deficiency is not very common. However, in areas where food is scarce, niacin deficiency is more common.  Niacin deficiency can result in indigestion, fatigue, vomiting, and depression.

You cannot overdose on niacin through food alone, however, you can if you take too much niacin in supplement form.  Overdose symptoms include skin flushing, dizziness and rapid heartbeat.

Vitamin B5 (Pantothenic acid)

Pantothenic acid largely helps us to help metabolize our food. Vitamin B5 also helps us to produce certain hormones. Pantothenic acid deficiency is rare, however, it may be indicated by fatigue, insomnia, depression, stomach pain, upper respiratory infections, vomiting, and burning feet. Some studies also suggest that pantothenic acid may improve symptoms associated with rheumatoid arthritis. High doses of this vitamin may cause diarrhea and increased bleeding risk.  It is found in most meat and vegetables.

Vitamin B7 (Biotin)

Biotin helps us to break down fats. It is synthesized in our GI tract and it is not clear that we require additional biotin in our diets. Maintaining a healthy GI tract flora of bacteria will help to maintain good biotin production. Biotin deficiency is not common. However, symptoms of biotin deficiency include dry eyes, fatigue and insomnia, depression, dry skin, cracked mouth, a swollen tongue that is magenta, and loss of appetite. Studies suggest that infants deficient in biotin may develop Cradle Cap. However, studies don’t necessarily support that biotin supplementation in infants will decrease Cradle Cap symptoms. As always, it is important for you to contact your healthcare provider before giving your infant a vitamin supplement.

Visit the Growing Healthy Together Fullscript page for a look at the vitamin and mineral supplements that we prefer. 


Finally, if you are unsure about your B vitamin levels, a lab test can identify if you or your child are deficient. If you choose to provide nutrients in the form of supplements, it is still important to maintain good health in other ways. As always, keep all supplements out of reach of children.

For a more in-depth look at deficiency and toxicity, check back in on our Vitamins and Deficiencies blog series, including the following:

For questions or concerns, respond to this blog or contact us.