Overview
Vitamin B6, also known as pyridoxine, is a water-soluble vitamin involved in a wide range of physiological and biochemical processes. It exists in multiple forms, including pyridoxine, pyridoxal, and pyridoxamine, with pyridoxal-5-phosphate being the biologically active coenzyme.
This active form acts as a coenzyme for more than 140 enzymes, playing a central role in amino acid metabolism, as well as carbohydrate and lipid metabolism. Vitamin B6 is widely distributed in foods and is essential for normal growth, development, and metabolic balance.
Symptoms
Clinical manifestations of altered vitamin B6 status are mainly related to deficiency or excess intake. Deficiency may present with skin rashes, a sore and glossy tongue, cracked lips, and a weakened immune system. Neurological symptoms such as depression, irritability, mental confusion, convulsions, and peripheral neuropathy can occur due to impaired neurotransmitter synthesis.
Hematological symptoms include microcytic or sideroblastic anemia, leading to fatigue, giddiness, and palpitations. Excessive intake over a prolonged period may result in numbness, headaches, fatigue, skin lesions, and convulsions.
Causes
Vitamin B6 deficiency may result from inadequate dietary intake, malabsorption, chronic illness, or increased metabolic demand. Conditions affecting protein metabolism, chronic alcoholism, and certain medications can interfere with vitamin B6 utilization.
Increased requirements are seen during pregnancy and lactation. Toxicity occurs mainly due to prolonged high-dose supplementation rather than dietary sources. Both deficiency and toxicity disrupt amino acid metabolism, neurotransmitter synthesis, heme production, and immune function.
Risk Factors
Individuals with poor nutritional intake, malnutrition, chronic liver or kidney disease, and gastrointestinal disorders are at higher risk of vitamin B6 deficiency. Elderly individuals, alcohol-dependent patients, and those on long-term drug therapy affecting metabolism are also vulnerable.
Pregnant and lactating women have increased requirements and may develop a deficiency if intake is inadequate. Unsupervised use of high-dose supplements increases the risk of vitamin B6 toxicity.
Prevention
Adequate intake of vitamin B6 through a balanced diet helps maintain normal metabolic and neurological function. Regular consumption of foods such as whole grains, eggs, fish, meat, bananas, milk, and vegetables supports sufficient levels. Awareness of the recommended daily allowance and avoiding unnecessary high-dose supplementation prevents toxicity. Early testing and correction of deficiencies in at-risk individuals reduces complications such as anemia, neuropathy, and immune dysfunction.
