The B complex vitamins include thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), B12, folic acid, and biotin. Without this family of 8 water-soluble vitamins the body wouldn’t be able to complete the chemical reactions needed to transform the food we eat into energy and a myriad of other metabolic actions impacting every cell in the body. Without adequate amounts of B vitamins, we simply wouldn’t be able to produce the energy required to live, let alone live with vitality. They are required for healthy nerve and brain function, intestinal health, blood cell formation, and cardiovascular health.

Because the B vitamins are water soluble, they cannot be stored at length in the body and any excess consumed is readily excreted. While many may do fine meeting the government’s minimum recommendations, some may require higher amounts for optimal health as a result of various circumstances that can increase one’s needs.

Stress and Anxiety- The body’s response to perceived stress can cause the release of stress hormones and speed up metabolic processes in the body which will use up greater amounts of B vitamins involved in these functions. Cortisol produced by the adrenal glands is released in response to stress and triggers the release of glucose from cells to use as energy, so you can theoretically run from the bear chasing you. Greater amounts of B vitamins involved in energy metabolism, such as thiamin(B1) and riboflavin(B2) will be used in this process. Pantothenic acid (vitamin B5) supports the adrenal glands, which can become fatigued with chronic stress. Vitamins B1, B6, and B12 are thought to support the formation of serotonin, a neurotransmitter that promotes relaxation.

Depression and Mood-Inadequate amounts of certain B vitamins can increase the risk of anxiety, depression and poor mood as these vitamins help support the health of the nervous system and brain. Low vitamin B6 may increase the risk of depression as it is involved in the tryptophan-serotonin pathway. A recent 2012 study has found that older adults with anemia and marginally low B6 and folate levels were more likely to be depressed. (Geriatr Psychiatry Neurol. 2012 Sep;25(3):170-8.) Both low folate and B12 have been found in those with depression and low folate levels can decrease effectiveness of antidepressant medication. NADH is the coenzyme form of niacin and may help improve mood and energy in those with chronic fatigue syndrome.

Pregnancy- Women who are pregnant, or who may become pregnant should make sure to take a multivitamin with folic acid. Folic acid is needed to help prevent neural tube birth defects. It must be taken in the earliest stages of pregnancy; therefore taking it before you are pregnant is advised by healthcare professionals. A recent study also found that prenatal intake of folic acid also was associated with a lower risk of autism.(JAMA. 2013 Feb 13;309(6):570-7)

Aging- B12 deficiency is estimated to impact 10-15% of adults over age 60 and may show up as impaired mental function. Reduced stomach acid production impairs absorption of B12 from food in this population. Low stomach acid may contribute to bacterial over growth in the small intestines and these bacteria may take additional B12 for their own use.

Medication- Young and old on proton-pump inhibitors for lowering stomach acid and those on metformin, a common drug used to treat type 2 diabetes, may be at risk for B12 deficiency. Anti-inflammatory steroid medications, oral contraceptives, and loop diuretics deplete vitamin B6. Folic acid depleting drugs include many anti-inflammatory medications including steroids and NSAIDs, antibiotics, H2 blocker antacid medication, certain diuretics and some birth control medicines. These are just a few possible drug-vitamin interactions. Talk with your pharmacist about specific ones you may be at risk for.

Disease- Those with celiac disease, crohn’s, or inflammatory bowel disease can have absorption problems increasing the risk of B vitamin deficiency (and others). Those with type 1 or type 2 diabetes may benefit from a synthetic form of thiamin call benfotiamine which has been shown to be effective at slowing the progression of common complications associated with diabetes, including neuropathy and nerve pain, retinopathy, and kidney damage. Elevated homocysteine in those with cardiovascular disease is treated with folic acid, B6, and B12. Alcoholism depletes the B vitamins, especially thiamin and B12.

For those individuals who have greater B needs or the elderly who have a decreased ability to convert B vitamins into the active coenzyme, they may want to look for supplements that are already in the coenzyme form of the vitamin. This is the more active form of the vitamin that does not need to be converted in the body. Some coenzyme forms include TPP for thiamin (B1), NADH for niacin (B3), FMN for riboflavin(B2), and methylcobalamin or adenosylcobalamin for vitamin B12.

2013 Megan Witt, RD, LD


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