Vitamin B6 refers to a group of chemically very similar compounds which can be interconverted in biological systems. Vitamin B6 is part of the vitamin B group, and its active form, pyridoxal 5′-phosphate (PLP) serves as a coenzyme in many enzyme reactions in amino acid, glucose, and lipid metabolism.
The family of B vitamins, which are also known as B complex vitamins, plays an important role in converting food into energy and helping the body metabolize fats and proteins. The B vitamins are also important for healthy hair, skin, liver, and eyes. Vitamin B6, or pyridoxine, is one in this group of eight vitamins.
Vitamin B6 helps a lot of the systems in your body function. It is important for cardiovascular, digestive, immune, muscular, and nervous system function. It is one of the vitamins that are behind the scenes. The B6 vitamin is needed for proper brain development and function and to make the hormones serotonin and norepinephrine, which affect mood.
Vitamin B6, along with the other B vitamins, helps the body turn food into energy. On its own, vitamin B6 has many other uses that are important to maintaining a healthy body and developing a healthy brain. Vitamin B6 is so important it may have triggered the growth of the first living creatures on Earth.
The fact that B vitamins are so important to our nutritional status coupled with the fact that they are water soluble — they are not stored in your body to any major extent — makes it quite easy to run dry on supplies.
Since the body can so easily run out of B6, it is important to consume foods that contain B6. Some of the best sources of B6 include beans, poultry, fish, fortified cereals, dark leafy greens, papayas, oranges and cantaloupe. Bananas are another good source.
Vitamin B6 may have given rise to Earth’s first oxygen-producing organisms. Around 2.4 billion years ago, the planet experienced a huge spike in atmospheric oxygen levels. Scientists have long held that this rise in oxygen, called the Great Oxygenation Event, was tied to the arrival of the first photosynthetic organisms. (Oxygen is a byproduct of photosynthesis, which uses sunlight to turn carbon dioxide into sugary foods.) But nobody knew why these oxygen-producing organisms emerged in the first place.
Researchers found that the oldest oxygen-based process involved the production of pyridoxal, a form of vitamin B6, about 2.9 billion years ago, the same time that the enzyme manganese catalase appeared.
Manganese catalase breaks down hydrogen peroxide into water and oxygen. Early organisms may have come across this enzyme when trying to cope with environmental hydrogen peroxide, which some geochemists believe was abundant in Earth’s glaciers at the time and was released by the bombardment of solar radiation. The organisms essentially got the oxygen they needed to produce pyridoxal by breaking down the glacial hydrogen peroxide with manganese catalase.
Pyridoxine is used for preventing and treating low levels of pyridoxine (pyridoxine deficiency) and the “tired blood” (anemia) that may result. It is also used for heart disease; high cholesterol; reducing blood levels of homocysteine, a chemical that might be linked to heart disease; and helping clogged arteries stay open after a balloon procedure to unblock them (angioplasty).
Women use pyridoxine for premenstrual syndrome (PMS) and other menstruation problems, “morning sickness” (nausea and vomiting) in early pregnancy, stopping milk flow after childbirth, depression related to pregnancy or using birth control pills, and symptoms of menopause.
Pyridoxine is also used for Alzheimer’s disease, attention deficit-hyperactivity disorder (ADHD), Down syndrome, autism, diabetes and related nerve pain, sickle cell anemia, migraine headaches, asthma, carpal tunnel syndrome, night leg cramps, muscle cramps, arthritis, allergies, acne and various other skin conditions, and infertility. It is also used for dizziness, motion sickness, preventing the eye disease age-related macular degeneration (AMD), seizures, convulsions due to fever, and movement disorders (tardive dyskinesia, hyperkinesis, chorea), as well as for increasing appetite and helping people remember dreams.
Some people use pyridoxine for boosting the immune system, eye infections, bladder infections, and preventing cancer and kidney stones.
Pyridoxine is frequently used in combination with other B vitamins in vitamin B complex products.
Vitamin B6 helps in controlling the level of fat that is deposited in and around the human heart and thus, protects against a number of cardiac diseases.
Vitamin B6 prevents this buildup, thereby reducing the risk of heart attack. Pyridoxine lowers blood pressure and blood cholesterol levels and keeps blood platelets from sticking together. All of these properties work to keep heart disease at bay.
Vitamin B6 also helps to restrict stone formation in the kidneys, hence keeping this critical organ of the human body in good shape.
Pyridoxine, teamed up with magnesium, prevents the formation of stones. It usually takes about three months of supplementation to make blood levels of these nutrients sufficient to keep stones from forming.
Premenstrual syndrome (PMS)
There is some evidence that taking pyridoxine by mouth may improve PMS symptoms, such as breast pain, depression, or anxiety in some women.
Vitamin B6 has long been publicized as a cure for premenstrual syndrome (PMS). Study results conflict as to which symptoms are eased, but most of the studies confirm that women who take B6 supplements have reductions in bloating, breast pain, and premenstrual acne flare, a condition in which pimples break out about a week before a woman’s period begins.
There is strong evidence that pyridoxine supplementation, starting ten days before the menstrual period, prevents most pimples from forming. This effect is due to the vitamin’s role in hormone and prostaglandin regulation. Skin blemishes are typically caused by a hormone imbalance, which vitamin B6 helps to regulate.
Mental depression is another condition which may result from low vitamin B6 intake. Because of pyridoxine’s role in serotonin and other neurotransmitter production, supplementation often helps depressed people feel better, and their mood improves significantly. It may also help improve memory in older adults.
Women who are on hormone-replacement therapy or birth control pills often complain of depression and are frequently deficient in vitamin B6. Supplementation improves these cases, too.
Low intakes of pyridoxine can slow down the immune system. Several different immune components become rather sluggish and critical prostaglandins levels decrease in the absence of adequate vitamin B6, making a person more susceptible to diseases.
Vitamin B6 plays an important role in refurbishing the immune system of the human body to the required functional level. This helps the human body to withstand a number of infections, which can easily victimize the body in the absence of this important vitamin.
People with asthma can benefit from pyridoxine supplements. Clinical studies of the nutrient show that wheezing and asthma attacks decrease in severity and frequency during vitamin B6 supplementation.
Anyone with breathing difficulties who is taking the drug theophylline may want to consider supplementation with this vitamin. Theophylline interferes with vitamin B6 metabolism. Supplementation not only normalizes blood levels but also helps limit the headaches, anxiety, and nausea that often accompany theophylline use.
Deficiency and dosage
Though a major deficiency in vitamin B6 is rare, many people may have a slight deficiency. People most likely to have a deficiency are children, the elderly, and those who take certain medications that can cause low levels of B6.
People who have trouble absorbing vitamin B6 from food or dietary supplements can develop a deficiency, as well. They include those with kidney disease, alcoholism, hyperthyroidism, autoimmune disorders such as rheumatoid arthritis, and inflammatory bowel disease such as celiac disease, or Crohn’s disease.
Symptoms of vitamin B6 deficiency include weak immune system, anemia, itchy rashes, scaly skin on the lips, cracks at the corners of the mouth and a swollen tongue. Other symptoms of a very low vitamin B6 levels include depression and confusion.
The recommended dietary allowance (RDA) for adult men and women up to the age of 50 is 1.3 milligrams daily. Men over 50 have an RDA of 1.7 mg, while women over 50 have an RDA of 1.5 mg. One cup of cooked kidney beans contains 0.2 mg of vitamin B6, while a large orange has about 0.1 mg.
Vitamin B6 causes interactions with some medications, so be sure to contact a medical professional before taking a pyridoxine supplement. For the most part, though, B6 is considered safe to consume naturally through foods and through moderate supplementation because it is a water-soluble vitamin. “In general, most vitamins fall into either one of two broad categories — water or fat soluble. Water soluble vitamins are for the most part eliminated daily, where fat soluble vitamins are stored within the body’s tissues.
Persistent consumption of excessively high doses of B6 can cause severe sensory nerve damage, leading to numbness, sensory changes and loss of control of bodily movements.