Table of Contents
- What is Vitamin B6?
- Signs of Vitamin B6 Deficiency
- Health Benefits of Vitamin B6
- Low B6 Levels Associated with Depression
- Can Help Reduce Anxiety
- Improves Cognitive Function
- Better Sleep Cycles
- Enhances Skin Health
- Appropriate Histamine Response
- Can Support Healthy Weight Loss
- Reduces Premenstrual Syndrome Symptoms
- Improves Digestive Health
- Balances Blood Sugar Levels
- Prevents/Treats Anemia
- Treats Early Pregnancy Symptoms
- Pain Management
- Bone Health
- Minimizes Risk of Cardiovascular Disease
- Minimizes Risk of Cancer
- Treats Certain Inflammatory Conditions
- Best Vitamin B6 Foods
- Vitamin B6 Precautions
Vitamin B6 is naturally present in a wide variety of foods, in addition to being available in supplement form.
In spite of how readily accessible it is, not everyone realizes just how much Vitamin B6 benefits the body.
It is highly versatile and it can have numerous effects, from elevating your immune system to improving your mental state.
So, just what is Vitamin B6?
Read on to learn everything you need to know about this essential vitamin.
What is Vitamin B6?
B6 (also labeled as Pyridoxine) is not just a simple vitamin.
The term itself is actually a generic substitute name for six compounds.
Three of them are as follows: pyridoxine (PN), which is an alcohol, pyridoxal (PL), which is an aldehyde, and pyridoxamine (PM), which contains an amino group (1).
The remaining compounds in B6 are made up of the 5′-phosphate esters of the first three compounds: pyridoxine 5′ phosphate (PNP), pyridoxal 5′ phosphate (PLP), and pyridoxamine 5′ phosphate (PMP).
In humans, the primary excretory form of B6 is 4-pyridoxic acid (4-PA); on the other hand, PMP and PLP are found in animal tissues, and plant-derived foods mainly contain PN and PNP (2).
As mentioned previously, Vitamin B6 can help perform a number of tasks.
PMP can be found affecting amino acid metabolism, and PLP does the same, in addition to helping to metabolize carbohydrates, lipids, and one-carbon units.
Generally, in coenzyme forms, Pyridoxine is involved in over 100 different enzyme reactions that mainly handle metabolizing protein (1).
PLP has an important role in this process, and PLP-dependent enzymes have been broken down into the following five structural classes:
- Fold Type I: Aspartate aminotransferase family
- Fold Type II: Tryptophan synthase family
- Fold Type III: Alanine racemase family
- Fold Type IV: D-amino acid aminotransferase family
- Fold Type V: Glycogen phosphorylase family
First isolated in the 1930s, Pyridoxine is what is known as a water-soluble vitamin (3).
In other words, it dissolves in water.
Our bodies are unable to store it; much of the leftover B6 in our system eventually leaves through our urine.
Furthermore, we cannot synthesize it on our own.
Because of this, it is important that we maintain a good supply of it from outside sources.
Signs of Vitamin B6 Deficiency
Inadequate absorption of B6 is relatively rare, but a significant number of cases of this can be found in areas where malnutrition is prevalent (4).
People may suffer from a Pyridoxine deficiency and not even realize it at first.
Those who suffer from the following conditions are at a greater risk of developing this deficiency:
- Alcohol Dependence: As alcohol is a producer of acetaldehyde, this causes a decrease in net PLP formation by cells. This can increase those cells’ susceptibility to hydrolysis, especially since acetaldehyde also competes with PLP in terms of protein binding (1). Low B6 further affects alcoholics because of poor dietary intake (3).
- Autoimmune Disorders: Those with celiac disease, Crohn’s disease, inflammatory bowel disease, rheumatoid arthritis, and more, tend to have a low count of plasma PLP concentrations. When it comes to those with arthritis, B6 can decrease further, depending on how severe arthritis’ inflammation is (1).
- Malnutrition: This is a phenomenon seen often in developing countries, especially in children. Those who struggle with eating disorders, or elderly individuals, can find themselves in this predicament as well. In this case, the immune system function is decreased, which can negatively impact B6 levels (4).
- Poor Renal Function: No matter the severity of the impairment of renal function, those who have this issue are frequently found to be deficient in B6. Even those who are undergoing dialysis or have received a transplant often wind up with low plasma PLP concentrations (1).
Though the above situations are more obvious causes of Vitamin B6 deficiency, seemingly healthy individuals can still feel the effects of low B6.
Mild cases generally see few to no symptoms for months.
As the deficiency continues, however, the signs increase.
No matter your health situation, there are some symptoms you should be aware of that may indicate a low vitamin count.
Children and adults can experience more serious signs of a deficiency in Pyridoxine.
These can include difficulty concentrating, muscle weakness, depression, nervousness, short-term memory loss, swollen tongue, weakened immune function, sores/ulcers in the mouth, and scaling on the lips/cracks at the corner of the mouth (1,3,5).
Health Benefits of Vitamin B6
Low B6 Levels Associated with Depression
There have been a number of studies that have shown that a Pyridoxine deficiency can contribute to increased symptoms of depression, much of which is based on the detection of low plasma levels of PLP in patients (6).
Additional research has been conducted to showcase that a higher intake of B6 can positively impact depressive symptoms; however, these results are largely seen in women rather than men (7).
Some additional research also noted that the uptake in Vitamin B6 consumption was seen mainly through foods that are right with the vitamin.
These foods were shown to elevate energy levels in women, a factor that can seemingly improve signs of depression.
It should further be noted that there has been similar research conducted on older men dealing with depression that did not yield the same positive results (8).
Women appear to be far more susceptible in terms of treating depression with B6 than compared to older men.
Can Help Reduce Anxiety
Signs of anxiety can occur in just about anyone of any age.
Anxiety is especially visible in patients who suffer from panic and/or hyperventilation attacks.
There has been shown to be a connection between these disorders and Vitamin B6.
Testing has been done that indicates patients who have these disorders are known to have reduced serotonin levels, which is one of the main causes of panic and hyperventilation attacks (9).
As B6 plays a role in synthesizing serotonin, it is suggested that by increasing the intake of the vitamin, you can better treat the anxiety that is associated with these disorders.
Further research has also shown that anxiety has been treated relatively well in cases where people have obsessive-compulsive disorder, as well as in children with autism (10).
In these instances, a greater amount of success in alleviating symptoms like anxiety is seen when the B6 intake is combined with another nutrient such as magnesium.
Improves Cognitive Function
It has been suggested that elevated concentrations of homocysteine and, in turn, low levels of B6 can contribute to cognitive impairment and decline (11).
This can lead to brain damage and other debilitating diseases.
It is a factor that has been largely observed in middle-aged and elderly patients.
Because of this, testing was done on this age group to determine whether or not an increase in the vitamin could aid in improving cognitive health.
In the research test groups, it was shown that Vitamin B6 benefits cognitive health in such a way that it can significantly reduce serum total homocysteine (tHcy) levels (12).
This process is especially helpful when B6 is taken in supplement form; even then, it can better aid cognitive health when used alongside additional vitamins such as B12.
Better Sleep Cycles
Research has shown that depleted levels of Pyridoxine can potentially disrupt your sleep patterns (13).
It also can negatively impact you on a psychological level, which can contribute to poor sleep.
Increasing your levels of Vitamin B6 so that you have a steady, healthy amount in your system appears to be able to improve your overall mental state and help you sleep.
Other than just help you get a better night’s rest, B6 can also affect the way you dream.
Studies indicate that B6 can improve your dream recall, allowing for more vivid dreaming (14).
This appears to be due to the possibility that the vitamin can increase cortical arousal during rapid eye movement (REM) sleep.
Enhances Skin Health
Deficiency in Pyridoxine can affect the maturation of collagen, leading to issues with the skin, such as lesions (15).
In this case, increasing the amount of B6 in a diet can have some positive effects on your overall skin health.
Collagen can become more soluble; this can lead to better elasticity in the skin, as well as allowing you to maintain that elasticity over time.
Studies have further indicated that B6 levels can help with overall skin development.
With acne, it doesn’t appear to do much at first since large concentrations of B6 can actually cause acne (16).
However, B6 is also capable of synthesizing testosterone, which can help regulate hormone levels (17).
Hormonal imbalance is one of the causes of acne.
So, by regulating these hormones, you can help treat acne with B6.
It is important not to take too much of it, though, as large amounts can have the opposite effect.
Appropriate Histamine Response
Pyridoxine is essential in handling histamine.
Histamine itself is a biogenic amine, and it is synthesized via the amino acid histidine found in B6 (18).
In turn, B6 is also needed to support the functioning of diamine oxidase (DAO), an enzyme that actually breaks down histamine.
As histamines are known to cause headaches, lowering the amount of histamine can decrease that suffering (18).
By increasing the amount of B6 in your body, you can help DAO, and break down any excessive amounts of histamine.
Overall, Vitamin B6 plays an important role not just in synthesizing histamine, but in assisting the enzyme that can break it down.
It is a much-needed vitamin that helps maintain a proper balance of histamine.
Can Support Healthy Weight Loss
B6 encouraging weight loss has much to do with eating healthy meals rich in the vitamin.
Paired with a calorie-restricted diet, increasing the amount of B6 in a diet via vitamin-rich cereal grains has shown to have influence not just on B6 levels, but on maintaining muscle mass (19).
PLP levels increase when such a diet is followed, which can also increase the B6/protein ratio (19).
Higher levels of PLP have been associated with a much greater increase in muscle mass percentage.
A B6-rich diet can also help maintain this muscle mass as you continue to lose weight, for a steadily-progressing weight-loss journey.
Reduces Premenstrual Syndrome Symptoms
Premenstrual syndrome (PMS) is a phenomenon that many women, teenagers, and young girls around the world suffer from.
It has been recommended that increasing B6, whether through supplements or diet changes, may cause improvement in these symptoms.
Though there has been some research done, additional work is required in order to determine just how well B6 can treat symptoms of PMS.
Even so, some of the benefits pertain more to decreasing the psychological impacts of PMS, such as moodiness and anxiety.
This is attributed to the fact that B6 is a cofactor in neurotransmitter biosynthesis (1).
Although additional testing may be needed, there is some good evidence that shows B6 can play a role in helping to reduce the severity of some PMS symptoms.
Improves Digestive Health
Individuals who may be suffering from digestive complications such as inflammatory bowel disease (IBD) or irritable bowel syndrome (IBS) usually have a low level of Pyridoxine in their systems (21,22).
PLP serves as a cofactor for more than 140 biochemical reactions, and plasma PLP concentrations have a relation to markers of inflammation (22).
Patients who do not have a high B6 count can find themselves suffering from worse symptoms from their conditions.
B6 can act as a regulator for overall gastrointestinal health so that the system functions properly.
It can provide nausea relief, reduce bloating and water retention, and affect your metabolism.
Whether or not you suffer from diseases like IBS or IBD, a healthy dose of B6 can improve the function of your digestive system.
Balances Blood Sugar Levels
In the treatment of type II diabetes, a trial was performed on 15 Caucasian men with the disorder, in addition to a control group of 13 healthy men (24).
Over the course of six weeks, they were given 150 mg/per day of Pyridoxine.
This eventually led to a decrease in the level of glycosylated hemoglobin (HbA1c).
Women in late pregnancy with gestational diabetes were tested in another study; they were given 100 mg/per day of B6 for two weeks (25).
Blood glucose levels were found to be lowered, and the women saw a great improvement in their glucose tolerance.
Studies have shown that it is possible to develop anemia due to a deficiency in Vitamin B6.
Low folate levels and a below-normal level of hemoglobin can cause certain types of anemia (26).
This can make you feel fatigued, and can even cause a depressed mood.
If you have a vitamin-deficiency anemia, then you can receive treatment either through injections or orally via supplements.
Adding supplements to your routine can typically improve anemia (27).
Of course, one of the best ways to deal with anemia is to prevent it in the first place.
If you manage to keep a good amount of B6 in your system, you should reduce your chances of developing a vitamin-deficiency anemia.
Treats Early Pregnancy Symptoms
Nausea and vomiting during pregnancy (NVP) are often simply referred to as ‘morning sickness.’
It is a symptom that most women experience while in the beginning stages of a pregnancy.
Using B6 to treat morning sickness has been standard since the 1940s (3).
Though it has been used for decades, studying the effects in a clinical trial is a bit difficult since NVP typically goes away on its own, and many women don’t bother with treatment.
From what was studied, Pyridoxine benefits women in the early stages of pregnancy by decreasing the severity of nausea and vomiting.
The effects were shown rather clearly in a study that compared ginger, a well-known anti-nausea and anti-vomiting remedy, and B6 (28).
In the study, not much difference was seen between the two, showing that both managed to lessen the severity of the vomiting and nausea.
B6 has been shown to treat early pregnancy symptoms to the point that The American Congress of Obstetrics and Gynecology (ACOG) actually recommend a supplement of 10-15 mg of B6 3-4 times daily for pregnant women to treat nausea and vomiting (1).
Chronic pain is seen in quite a few people who have low Vitamin B6 levels.
And CTS can cause more than just pain; it can bring about numbness and weakness in the hands and fingers.
There have been a number of studies seeking to determine how well B6 can help manage pain.
Those studies on symptoms of CTS found that a B6 deficiency doesn’t have a direct connection to CTS.
However, low blood levels of PLP have been connected to increased pain (3).
As such, it seems beneficial to add B6 to your diet in order to help treat pain, no matter the cause.
Several studies were conducted to discover a relationship between bone health and B6, in particular on older patients who were dealing with osteoporosis (30).
Low B6 counts were shown to contribute to low bone mineral density (BMD).
With a low BMD, you can increase your risk of experiencing bone fractures.
More associations between B6 and bone health center around bone marrow deficiency.
Being low in the vitamin can reduce the number of null cells (lymphocytes) and neutrophils (granulocytes) in the body, which then can lead to a bone marrow deficiency (31).
Minimizes Risk of Cardiovascular Disease
There have been numerous studies done to try to find a correlation between Pyridoxine and cardiovascular disease.
Additional testing is needed to discover without a doubt that B6 can benefit cardiovascular health.
However, the research that has been done did return some significant results.
A test conducted in Japan, though limited in scope, produced results that a high intake of B6, as well as dietary folate, can help decrease the risk of mortality from certain diseases like heart failure and stroke (32).
Another study concluded that low amounts of PLP are found to be related to high C-reactive protein (CRP) concentrations; these are, in turn, related to a higher risk of coronary artery disease (CAD) (33).
Even though the previous study showcased how results of high CRP can impact cardiovascular disease, another study showed that B-vitamins do not have a significant effect on levels of inflammatory markers (34).
Minimizes Risk of Cancer
There hasn’t been any conclusive research done that shows Pyridoxine improves mortality rates or outright prevents cancer, but additional research has shown that low B6 concentrations may be associated with a greater risk of some types of cancer (1).
A connection found between B6 and cancer was shown in a case study in women with cancer of the cervix; in this study, those women were found to have a deficiency in B6 (35).
At the same time, the study didn’t completely conclude whether the deficiency had anything to do with the disease.
Vitamin B6 can further assist in reducing the risk of cancer in the way it affects our immune system.
Treats Certain Inflammatory Conditions
There is some research that indicates low Vitamin B6 concentrations are related to higher levels of inflammatory markers (C-reactive protein) (36).
That said, it appears that by improving the low plasma PLP can benefit particular inflammatory conditions.
These conditions include digestive issues like IBD.
Other inflammatory conditions like rheumatoid arthritis have been shown to improve somewhat from an increase in Vitamin B6.
This is because patients with the illness typically have been shown to have a low Pyridoxine count (37).
The research, in this case, proved that supplementing Vitamin B6 didn’t necessarily clear the symptoms of rheumatoid arthritis, but it did decrease the vitamin deficiency.
Best Vitamin B6 Foods
Pyridoxine can be found in a vast variety of foods, but it has been indicated that B6 intake from food alone only contributes roughly 1.9 mg/daily (3).
In plant foods, B6 is only half as bioavailable as compared to other B6-rich foods; this is because the plant foods contain a form of B6 known as pyridoxine glucoside (3).
There are certain foods that are richer than others in B6.
For instance, beef liver and other kinds of organ meats, fruit (not citrus), fish, and potatoes and similar starchy vegetables, are some of the richest sources (1).
The following list provides information about some of the most frequently-consumed Vitamin B6-rich foods:
- Fortified breakfast cereal (1 cup) = 0.5-2.5mg/serving
- Canned chickpeas (1 cup) = 1.1mg/serving
- Pan fried beef liver (3 ounces) = 0.90mg/serving
- Yellowfin fresh tuna, cooked (3 ounces) = 0.90mg/serving
- Wild salmon, cooked (3 ounces) = 0.48-0.80mg/serving
- Russet potatoes w/ skin, baked (1 medium) = 0.70mg/serving
- Turkey, light meat cooked/roasted (3 ounces) = 0.4-0.69mg/serving
- Roasted chicken breast (3 ounces) = 0.50mg/serving
- Avocado (1 medium) = 0.52mg/serving
- Cooked spinach (1 cup) = 0.44mg/serving
- Banana (1 medium) = 0.43mg/serving
- Marinara (spaghetti) sauce, ready to serve (1 cup) = 0.40mg/serving
- Pitted dried plums (1 cup) = 0.36mg/serving
- Ground beef patty, 85% lean (3 ounces) = 0.30mg/serving
- Dry roasted hazelnuts (1 ounce) = 0.18mg/serving
- White, long-grain enriched rice (1 cup) = 0.10mg/serving (1, 3)
You can check out the USDA Food Composition Database if you want to learn even more about the nutrient availability in these foods and more.
Vitamin B6 Precautions
As with any dietary supplement, it is important that you don’t start on a B6 supplement until you have spoken to your healthcare provider.
There are a number of potential side effects and interactions with medication that you could experience, so let your doctor know you are increasing your Vitamin B6 intake, and keep them up to date on any changes.
Below are some of the common risks associated with excessive B6 intake, proper dosing, and any interactions you may have.
Vitamin B6 Risks
There are some reports of allergic skin reactions to higher doses of B6 (5).
Other symptoms that appear to be mild but still warrant a checkup with your doctor include nausea, headache, photosensitivity, heartburn, additional gastrointestinal symptoms, and loss of appetite (1, 5).
Some people may experience more severe reactions to excessive Pyridoxine consumption.
A study showed that chronic administration of B6 (1-6g orally) per day over a course of 12-40 months can cause a serious adverse reaction to progressive sensory neuropathy by ataxia (1).
In other words, it can cause severe loss of control of bodily movements.
The symptoms and side effects of excessive B6 do appear to stop, though, if a patient discontinues taking the vitamin.
Vitamin B6 Dosing
If you normally eat a balanced diet, you shouldn’t be concerned with the dosing of Vitamin B6.
There is a safe daily recommended amount depending on age.
The following describes the tolerable upper-level amount of B6 safe to consume.
This consumption mainly occurs from food and formula:
- Infants 0-12 months: cannot establish
- Children 1-3 years: 30mg
- Children 4-8 years: 40mg
- Children 9-13 years: 60mg
- Adolescents 14-18 years: 80mg
- Men/Women 19 years+: 100mg (3)
Vitamin B6 Interactions
There are some medications that can reduce blood levels of Pyridoxine, so again, it’s important to keep your physician informed of all medications, supplements included, that you are taking, in the event that they interact with your B6.
Some common medications that can lower your B6 levels include the following:
- Cycloserine (Seromycin®): A broad-spectrum antibiotic used for the treatment of tuberculosis. This can increase the urinary excretion of B6.
- Theophylline: Is used by those with asthma, chronic bronchitis, and other lung diseases. Patients using this tend to have low plasma PLP concentrations.
- Antiepileptic Medications: Some of these medicines increase the catabolism rate of B6 vitamin, which causes low plasma PLP concentrations (1).
Pyridoxine can interfere differently with other medications as well.
When it comes to antibiotics (tetracycline), all B-complex vitamins disrupt the effectiveness of absorption.
It’s best not to take B6 supplements at the same time as taking this kind of medication.
B6 can affect some antidepressants, as well.
Supplements with this vitamin can improve the effectiveness of some tricyclic antidepressants.
On the other hand, antidepressants known as monoamine oxidase inhibitors (MAOIs) can wind up reducing blood levels of B6 (5).
Whenever you are increasing your intake of Pyridoxine, let your doctor know so that they can properly monitor you, especially if you are taking additional medications.