We are accustomed to hearing about the vitamins and minerals we need to avoid nutritional deficiencies and maintain good health.
Vitamin B, of which there are many different types, is all too often overlooked – a great shame given the many functions it performs.
In this article, we aim to outline the various roles of B-complex vitamins, discuss symptoms of deficiency and suggest means of maintaining your intake.
How Many B Vitamins Are There?
From a nutritional standpoint, there are eight B vitamins you need to know about. These eight are classed as essential, since, in the main, they cannot be manufactured by the body.
Although each of the water-soluble B vitamins has its own role and function(s), some also work in tandem with one another. This is not uncommon in a dietary sense. For example, vitamin D and calcium have a synergistic relationship, and so too do sodium and potassium.
Let’s go ahead and list the key B vitamins, then.
• Vitamin B1 (Thiamin)
• Vitamin B2 (Riboflavin)
• Vitamin B3 (Niacin)
• Vitamin B5 (Pantothenic Acid)
• Vitamin B6 (Pyridoxine)
• Vitamin B7 (Biotin)
• Vitamin B9 (Folic Acid)
• Vitamin B12 (Cobalamin/Methylcobalamin)
You will find B vitamins in a variety of foods, and also isolated in supplement form. Additionally, a range of B-complex vitamins are often included in multivitamin supplements or whole-food powders.
Maximum Vibrance, for example, contains all eight essential B vitamins, including 500% of your daily vitamin B1.
How B Vitamins Work
It is crucial to remember that a deficiency of any B vitamin can set the stage for health problems. Taking each in turn, we’ll assess how these nutrients perform in the body.
Not only was vitamin B1 the first B vitamin to be discovered (in 1911), but in isolating the nutrient the German chemist Casimir Funk actually coined the term vitamin: to express the vital nature of the nutrient.
Vitamin B1 plays an essential role in breaking down carbohydrates and converting food into energy. It’s also involved in muscle contraction and the nervous system.
While many nutrients have an effect on stress, thiamin is often dubbed the “anti-stress” vitamin, since it enhances the body’s ability to withstand stressful situations.
Supplementation with vitamin B1 has been shown to modestly reduce blood pressure, particularly in patients with hyperglycaemia (Alaei-Shahmiri et al., 2015).
According to cardiovascular research scientist Dr. James DiNicolantonio, “patients with heart failure – especially those in advanced stages – may benefit from regular thiamin supplementation.”
Furthermore, severe vitamin B1 deficiency may be a factor in infertility and miscarriage, specifically by contributing to low-quality oocytes.
Food sources of vitamin B1 include liver, brewer’s yeast, wheat germ, potatoes, kidney and black beans, cashews, asparagus, spinach, mushrooms, sunflower seeds and Brussels sprouts.
While symptoms of B1 deficiency include lethargy, mood changes and disorderly thinking, it is not altogether common.
Vitamin B2, or riboflavin, performs a host of functions in the body. As well as contributing to the nervous system, it helps to maintain healthy skin, vision and red blood cells.
What’s more, scientific research shows vitamin B2 to be a potent antioxidant, fortifying the body against oxidative stress (especially lipid peroxidation and reperfusion oxidative injury) and taming renegade free radical molecules.
Indeed, the EU Register on Nutrition and Health Claims states that riboflavin is the only B vitamin to achieve antioxidant status.
According to a 2017 review published in the journal Frontiers in Neurology, the nutrient has significant neuroprotective potential. This is due to the way in which it ameliorates everything from mitochondrial dysfunction to neuroinflammation.
Food sources of vitamin B2 include liver, brewer’s yeast, almonds, mushrooms, leafy greens, eggs, seafood and wild rice. And while deficiency of the nutrient is not commonplace, it is not unheard-of either.
In European nations, for instance, it is estimated to affect 7-20% of the population, with symptoms manifesting as blurred vision, skin cracking and dermatitis.
Those who limit their dairy and meat intake may be at risk, and so too may people who exercise regularly (physical activity quickens riboflavin’s removal from the body). Women using the Pill could also benefit from supplementation, since such medication impacts B2 absorption.
Commonly known as niacin, vitamin B3 is just as important as its predecessor. Like riboflavin, it makes valuable contributions to the nervous system, metabolism and skin health.
Niacin is also critical for cellular energy production and highly beneficial for the cardiovascular system in particular.
In the words of James McKenney, professor emeritus at Virginia Commonwealth University’s School of Pharmacy, “niacin lowers harmful cholesterol and raises good cholesterol better than any drug we have.”
With that said, long-acting forms of niacin taken in high noses can cause liver damage, stomach upset and infection.
Niacin-rich foods comprise liver (a fertile source of B vitamins, as you’ll have noticed), chicken, pork and beef, as well as oily fish like anchovies, salmon and tuna. Vegetarian sources include potatoes, mushrooms and whole bran cereals.
It’s virtually impossible to consume too much niacin from the diet, but if supplementing in high doses, you should do so under close instruction from your practitioner.
Let’s skip over vitamin B4 since – despite the name – it’s not officially designated as a vitamin. The next essential nutrient on our list is good old vitamin B5, a.k.a. pantothenic acid.
Never heard of it? Don’t worry, you’re not alone.
The criminally under-appreciated, life-sustaining vitamin is needed by our bodies to synthesise hormones; combat fatigue; maintain healthy mental performance; and break down carbohydrates and fat for energy.
It’s also needed to form Coenzyme A (CoA), a necessary co-factor for multiple enzymes and vital for the synthesis/oxidation of fatty acids.
Sources of pantothenic acid include liver, chicken, beef, duck, kidney, potatoes, avocados and eggs. However, food processing is known to destroy up to 75% of vitamin B5. As such, the finest sources are unprocessed whole grains, fortified cereals or high-quality supplements.
Despite the negative impact of food processing, vitamin B5 deficiency remains highly uncommon due to the sheer number of dietary sources.
Since vitamin B6 is involved in well over a hundred cellular reactions, you won’t find many people talking it down.
In common with B2 and B12, vitamin B6 is responsible for manufacturing the red blood cells which provide oxygen to body tissues.
It also helps mental processes by creating neurotransmitters, enabling brain cells to communicate with one another. Indeed, low vitamin B6 intake appears to correlate with cognitive decline in older adults.
As if that wasn’t enough, vitamin B6 makes far-reaching contributions to the nervous and immune systems and regulates hormonal activity.
In summation, this is a powerhouse among B vitamins! Thankfully, deficiency is rare due to the plentiful vitamin B6 food sources available: chicken, pork, fish, whole grain cereals, eggs, vegetables, chickpeas, peanuts and milk, to name a few.
Although vitamin B7 – biotin – has a number of roles and responsibilities, it is often pigeonholed as a beauty vitamin. That’s because it has long been linked with enhancing the appearance of skin, hair and nails.
While it’s true that biotin helps maintain skin, hair and mucous membranes, it would do the nutrient a disservice to overlook its other duties.
For example, did you know the body needs biotin to process carbs, fats and amino acids? Or that it plays a role in the nervous system and psychological function?
Although only small amounts of biotin are found in food sources such as brewer’s yeast, chicken, pork, egg yolks, leafy green vegetables, soybeans and bananas, our clever native gut bacteria are able to manufacture it.
Fortunately, biotin deficiency is extremely rare. That said, diabetics tend to have lower levels, and biotin supplements can be useful in managing glucose levels.
People who have taken a lot of antibiotics are also at risk, since antibiotics wipe out the aforementioned intestinal bacteria that generate the B vitamin.
More widely known as folic acid (or folate, in its natural form), vitamin B9 works with around 20 enzymes to construct DNA; it’s also vital for proper nerve function.
Above all else though, it’s best known for its role in foetal health and development, protecting unborn babies from life-threatening birth defects of the brain, spine and heart.
Despite being one of the most valuable nutrients in existence, folic acid has just one permissible health claim approved by the EU Register: “Supplemental folic acid intake increases maternal folate status. Low maternal folate status is a risk factor in the development of neural tube defects in the developing foetus.”
Folic acid has also been linked to the reduction of memory loss and depression, and in one 2018 study from Israel, maternal folic acid intake corresponded with a reduction of autism in offspring.
Interestingly, folic acid also seems to dramatically improve cognitive performance (and reduce inflammation) among elderly people suffering from mild cognitive impairment.
What’s more, there is evidence to suggest folic acid protects against cancer of the ovaries, colon and cervix. Don’t hold your breath on the EU Register being updated any time soon, though!
B9 deficiency can cause a form of anaemia known as macrocytic anaemia, defined as blood with an inadequate concentration of hemoglobin.
Dietary sources of vitamin B9, meanwhile, include fortified cereals, dark leafy greens, citrus fruits, beans and lentils, okra, seeds, nuts, asparagus and cauliflower. However, as with vitamin B5, food processing can reduce folate content by as much as 50%.
What’s more, substances such as alcohol, tobacco and non-steroidal anti-inflammatory drugs can increase your need for the vitamin.
Lastly, we have vitamin B12 – probably one of the most well-known and important of the B-complex vitamins.
The reason it is more famous than the others is that B12 is found exclusively in animal products, making supplementation necessary for vegetarians and vegans.
This can be achieved through an intramuscular injection or, as most people prefer, via a daily sublingual B12 tablet.
As for why vitamin B12 is important, where to begin?! For starters, and as mentioned previously, B12 works with B2 and B6 to maintain a healthy red blood cell count.
B12 also contributes to the immune system, psychological function, metabolism, the process of cell division and energy levels.
What's more, B12 is critical to the production of myelin, the fatty sheath which insulates nerve fibres, ensuring the smooth flow of electric impulses throughout the body.
Vitamin B12 is actually closely connected with B9, in that both work to convert dangerous homocysteine to methionine. B12 also reactivates folic acid, converting it back into a form the body can use.
As such, a deficiency of vitamin B12 presages a deficiency of B9, and in fact B12 relies on B9 to deconstruct homocysteine. That makes the need for supplementation even more important for non meat eaters.
An array of ailments have been linked to low B12 status, including confusion, fatigue, decreased reflexes, reduced pain perception, tinnitus and memory loss.
The resultant inadequacy of myelin can also lead to disrupted nerve transmission.
It is not just vegetarians who need to think extra hard about their B12 intake. A lack of B12 among the elderly is associated with various health conditions, not least osteoporosis, dementia and anaemia.
One study performed in Canada a few years ago found that 13.8% of seniors moving into assisted living facilities were B12 deficient, with 38.3% exhibiting ‘subclinical’ deficiency.
This may be due to decreased absorptive ability amongst the elderly population.
Do I Need a Vitamin B Supplement?
In an ideal world, we could all rely on our diet to obtain not only the B-complex vitamins we need to maintain our health, but other, equally important nutrients: iron and calcium, vitamin D and C, magnesium…
It is a sad fact that many of us do not consistently follow a diet which provides these nutrients, and in some cases – as with vegetarians and vegans – some form of supplementation is required.
Because food processing such as canning and heat curing destroys certain B vitamins, it is always a good policy to choose fresh fruits, vegetables and meats over canned alternatives. Storage and preparation can also impact nutrient content.
As mentioned, pregnant women have a special need for supplemental folic acid (B9) and should take at least 400mcg daily from the moment contraception use stops until you are 12 weeks. Many pre-natal vitamins actually contain 600-1,000 mcg of folic acid.
If you have a family history of conditions such as spina bifida, it is likely you will require a higher daily dose altogether – anything up to 5mg folic – until you are 12 weeks pregnant.
Because of the interrelation of B9 and B12, as mentioned above, it would be sensible to ensure adequate B12 levels at the same time.
Browse our Vitamins and Minerals page to learn more, and as always, don’t hesitate to get in touch if you have any questions! Nutritional deficiencies are, more often than not, easy to rectify and can provoke a serious upswing in your health.