Vitamin B6, or pyridoxine, is a very active water-soluble vitamin. It exists in the forms of; pyridoxal, pyridoxol, pyridoxamine. These biologically active forms of the vitamin play a fundamental role in its ability to work as a coenzyme for amino acid (protein) synthesis. This particular coenzyme is critical in a variety of amino acid processes.
The coenzyme form of the Vitamin B6 is pyridoxal phosphate (PLP). PLP is responsible for the conversion of the amino acid –tryptophan- to the vitamin B2, or niacin; antibody, and hemoglobin molecule synthesis; and plays a key role in the regulation of certain enzymes in the Central Nervous System. This B-compound coenzyme may also prove critical in the formation of DNA and RNA, or the body’s genetic material or genetic code.
Vitamin B6 is often times supplemented in conjunction with Vitamin B9, and B12, to control homocysteine levels in the blood. This important amino acid has been connected to many chronic illnesses including the number one chronic disease and killer of adults in America, heart disease.
Intestinal bacteria manufacture the remaining half of all Vitamin B6 synthesized in our bodies.
|Food||Serving Size||%DV *|
|Ready-to-eat cereal, 100% fortified, 3/4 c||2.00||100|
|Potato, Baked, flesh and skin, 1 medium||0.70||35|
|Banana, raw, 1 medium||0.68||34|
|Garbanzo beans, canned, 1/2 c||0.57||30|
|Chicken breast, meat only, cooked, 1/2 breast||0.52||25|
|Ready-to-eat cereal, 25% fortified, 3/4 c||0.50||25|
|Oatmeal, instant, fortified, 1 packet||0.42||20|
|Pork loin, lean only, cooked, 3 oz||0.42||20|
|Roast beef, eye of round, lean only, cooked, 3 oz||0.32||15|
|Trout, rainbow, cooked, 3 oz||0.29||15|
|Sunflower seeds, kernels, dry roasted, 1 oz||0.23||10|
|Spinach, frozen, cooked, 1/2 c||0.14||8|
|Tomato juice, canned, 6 oz||0.20||10|
|Avocado, raw, sliced, 1/2 cup||0.20||10|
|Salmon, Sockeye, cooked, 3 oz||0.19||10|
|Tuna, canned in water, drained solids, 3 oz||0.18||10|
|Wheat bran, crude or unprocessed, 1/4 c||0.18||10|
|Peanut butter, smooth, 2 Tbs.||0.15||8|
|Walnuts, English/Persian, 1 oz||0.15||8|
|Soybeans, green, boiled, drained, 1/2 c||0.05||2|
|Lima beans, frozen, cooked, drained, 1/2 c||0.10||6|
|* DV = Daily Value. DVs are reference numbers based on the Recommended Dietary Allowance (RDA). They were developed to help consumers determine if a food contains very much of a specific nutrient. The DV for vitamin D is 400 IU. The percent DV (%DV) listed on the nutrition facts panel of food labels tells adults what percentage of the DV is provided by one serving. Percent DVs are based on a 2,000-calorie diet. Your Daily Values may be higher or lower depending on your calorie needs. Foods that provide lower percentages of the DV will contribute to a healthful diet.|
Studies suggest Vitamin B6, to be effective in the prevention and treatment of numerous physical and psychological afflictions. In combination with B9 (folate), pyridoxine may be the most important nutrient in the regulator of mood in our psyches’. Through clinical application we know that B6, alone, produces serotonin which dramatically increases our chances of preventing depression. Between 15-39% of all Americans suffering from depression may have low folate levels. Combined with B9 and B12, pyridoxine may be used to treat symptoms of clinical depression and overall “cognitive function” in individuals suffering from this psychological disease. These anti-stress hormones produced by pyridoxine, particularly serotonin, may also aid in the stressors associated with Human Immunodeficiency Syndrome, or even A.I.D.S.[6, 7]
In conjunction with a healthy diet, pyridoxine, may reduce the risks of having diseases associated with the heart. This is in direct correlation to the lowering of homocysteine levels in the blood. The supplementation of Vitamins B6, B9, and B12 may also be important in eliminating the risk factors associated with atherosclerosis.
A clinical study, including pyridoxine alpha-ketoglutarate (a particular compound of Vitamin B6), has proven its unique ability to control blood sugar levels in those suffering from diabetes. A recent study focused on fasting blood sugar levels in relation to Vitamin B6 supplemented in the diet. There proved to be significant reductions of those individuals supplementing with pyridoxine alpha-ketoglutarate, than those receiving placebo, or nothing at all.
The demographic of women concerning proper supplementation of pyridoxine has not been overlooked. Studies have shown lower levels of B6 to be associated with eating disorders, and increased Premenstrual Syndrome (PMS) symptoms.[11, 12] Supplementation with pyridoxine proved more successful than placebo at alleviating (mainly) depression in both eating disorders and stressors related to PMS. Lower levels of B6 in both men and women, however, have also been associated with rheumatoid arthritis and osteoporosis in various clinical applications.[13, 14]
Because of pyridoxine’s ability to produce essential brain chemicals, it has been used as an effective aid in the combatant against Attention Deficit/Hyperactivity Disorder (ADHD) amid children. Neurological chemicals such as dopamine, serotonin, and norepinephrine are dependent upon B6 for proper development and regulation. Supplementation with Vitamin B6 in children suffering from ADHD may improve overall hyperactive and cognitive behavior.
The RDA for Vitamin B6 was revised in 1998 and is in direct relation to the amount of protein consumed in an individual’s diet. This is due to amino acid metabolism by pyridoxine.
|19-30||1.3 mg/day||1.3 mg/day|
|50+||1.7 mg/day||1.5 mg/day|
|All Ages||1.9 mg/day||2.0 mg/day|
Vitamin B6 Deficiencies
Pyridoxine deficiency is among the most common of all deficiencies in humans. The United States Department of Agriculture (U.S.D.A.) has reported that some “80 %” of Americans consume less than the Recommend Dietary Allowance for Vitamin B6.
Although it is more stable than most B-complex vitamins, this deficiency continues to be prevalent among western societies. These deficiencies include and are not limited to:
- Mental confusion
- Itchy/scaly skin
- Inflamed mucous membranes of mouth
- Convulsions in infants
- Abnormal ECGs (electroencephalograms)
- Change in red blood cells (hypochromic/microcytic anemia)
- Changes in tryptophan metabolism
Vitamin B6 Toxicities
“Mega-doses” of Vitamin B6 can lead to toxicity in humans, although it is rare. The main sign of pyridoxine overdose is the destruction of our sensory nerves. This leads to the loss of feeling in the extremities (i.e. fingers, legs, etc.).
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