Vitamin B6, also referred to as pyridoxine, is a water-soluble vitamin. Water-soluble vitamins are not stored in the body and excess amounts of it are flushed out through the urine.
Functions of Vitamin B6
Vitamin B6 helps to convert food into energy. It helps the body produce various neurotransmitters that are required for sending and receiving signals from one nerve to another. It also helps maintain the normal levels of an amino acid, homocysteine. This vitamin is also known for its involvement in processes like gluconeogenesis and glycogenolysis. It helps in the production of serotonin, which is a mood enhancer. However, low levels of this vitamin lead to depression and mood fluctuations.
Food Sources of Vitamin B6
Vitamin B6 is found in both bound and free forms. It is available in a variety of food sources. Vitamin B6 is present as pyridoxine in plant foods and as pyridoxal or pyridoxamine in animal sources. The form of Vitamin B6 present in plant sources is far more stable than the one present in animal sources. Hence, plant sources lose very little vitamins as compared to animal sources. Cooking, storage, processing, freezing and canning all lead to loss of vitamin B6. The extent of loss depends on the form of vitamin present in the sources. Vitamin B6 is present in the following food items:
- milk
- banana
- avocado
- poultry
- fish
- beef liver
- organ meats
- whole grains
- legumes
- brown rice
- corn
- potatoes
- fruits (except citrus fruits)
- nuts
Factors Causing Vitamin B6 Deficiency
Deficiency of vitamin B6 is unlikely to occur if a balanced diet is consumed. A variety of factors that can lead to a deficiency of Vitamin B6 are listed below:
- Various medications that may hamper the absorption of vitamin from the diet
- Acute renal disease
- Malabsorption syndrome such as Crohn’s disease, celiac disease and ulcerative colitis
- Genetic disorders
Symptoms of Vitamin B6 Deficiency
Borderline or mild deficiency of vitamin B6 has no visible signs and symptoms. Moderate and severe deficiency leads to the following symptoms:
- nervousness
- depression
- memory loss
- muscle weakness
- difficulty in concentration
- irritability
Other serious complications of vitamin B6 lead to:
- occurrence of microcytic anaemia
- dermatitis
- glossitis
- depression
- confusion
- weakened immune response
Infants suffering from vitamin B6 deficiency suffer from the following symptoms:
- irritability
- convulsive seizures
- hearing impairment
Dosage of Vitamin B6 Supplements
The adequate intake recommendations for vitamin B6 are as follows:
Infants
- 0 – 6 months: 0.1mg/day
- 7 – 12 months: 0.3mg/day
Children
- 1 – 3 years: 0.5mg/day
- 4 – 8 years: 0.6mg/day
- 9 – 13 years: 1mg/day
Adolescents and Adults
For adolescents and adults, the RDA requirements vary according to the gender, as follows:
- Males aged 14 – 50 years: 1.3mg/day
- Males aged 50 years and above: 1.7mg/day
- Females aged 14 – 18 years: 1.2mg/day
- Females 19 – 50 years: 1.3mg/day
- Females aged 50 years and above: 1.5mg/day
The requirements are higher than the normal levels for pregnant and lactating women. For pregnant women, the requirement is 1.9mg/day and during the lactation period women are advised to take 2.0mg/day.