The Big B-Vitamin Breakdown

by Dr. David Minkoff February 28, 2018 7 min read

Surfer grinding his surfboard on the top of a cresting wave with the sun in the background..

What They Do, Why You Need Them, and Where to Get Them

We all know B vitamins are important, but how many of us really know why? Or what they even do?

We’re going to take a deep dive into this famous class of vitamins to get a deeper look at the differences between them, what they really do for us, and where you can look for richer dietary sources.

The B-Complex: Family Origins

When vitamins were first identified in the 1910s and 20s, they were named according to the alphabet. The first one was vitamin A. The second one was B, and so on. Pretty creative.

(The one exception to this is vitamin K, named because German chemists found that it was involved with Koagulation)

Eventually, as technology developed, scientists realized there was more than one compound they were calling “Vitamin B.” So they renamed it “B-Complex” and began naming the different B-complex components with numbers. The first one they isolated was B1, the second B2, and so on. Very creative, indeed.

But as the scientists continued refining their methods, several of the formerly-known-as-B-vitamins were reclassified, leaving large breaks in the B-vitamin numbers. So that’s why there’s no B4, B8 or B10.

What Do They Do?

B vitamins are a group of molecules that are all largely involved in energy production. We need them to break down food and make ATP, the biological currency of energy.

This is a complex process and requires many, many compounds– hence so many B-Vitamins.

They are all very different in structure and do different things, but we need them all. They work together and sometimes overlap in their function.

Generally speaking, B-vitamins help increase energy, ease stress, lower anxiety and depression, aid memory, and reduce heart disease.

So let’s look at these one at a time.

Vitamin B1 - Thiamine

Thiamine plays a number of roles in cellular metabolism, but is mostly involved with converting food into energy – especially carbs and sugars. This means if you eat a carb-heavy diet, you’ll need more thiamine in your diet to compensate. It also plays a role in muscle contraction, cardiovascular health, immunity, and supports nervous system function, which is in many supplements promoting brain health [1,2].

Food sources: whole grains, beans, spinach, kale, nuts, sunflower seeds, pork, and red meat.

Vitamin B2 - Riboflavin

Riboflavin is involved in virtually all metabolism, playing key roles in the breakdown of carbohydrates, fats, and protein. You need to get it every day to maintain healthy digestion and energy levels. It’s also involved with the production of steroid hormones essential for body growth, as well as a necessary role in red blood cell production. [3,4]

Food sources: almonds, wild rice, eggs, brussel sprouts, spinach, broccoli, salmon, and beef.

Vitamin B3 - Niacinamide (aka niacin)

Niacin is an incredibly important vitamin. It’s a precursor to NAD+/NADH, one of the most used molecules in the energy production cycle. It also is used in dozens of other critical biological processes – everything from DNA repair, HDL cholesterol production (the good cholesterol), and brain function. It improves skin and joint health by lowering inflammation – the underlying cause of both acne and joint pain. It’s also a potent vasodilator, which has shown to help impotence [5-7].

FUN FACT: because high doses cause skin flushing and tingling, some lower-quality supplements actually include niacin because it creates the impression that the pill is “doing something.” Caveat Emptor.

Food sources: beef, poultry, fish, legumes, nuts, eggs, beans, and green vegetables.

Vitamin B5 - Pantothenic Acid

In energy metabolism, B5 helps break down fats and carbohydrates. Other than this primary role, however, it is involved with growth and healing. It helps produce many of our hormones, especially as they relate to growth. It also plays a central role in wound healing, and higher doses of pantothenic acid can actually speed up the healing process. It appears to be important across virtually all of life, as it can be found in virtually every food group. Its name derives from the Greek word “pantothen” which means “from everywhere” [8,9]

Food sources: organ meats, egg yolk, whole grains, avocados, nuts, lentils, cruciferous vegetables, and dairy products.

Vitamin B6 - Pyridoxine

Pyrodixine takes part in over 100 different cellular reactions throughout the body (that we know about), and many of these are related to neurotransmitters. Vitamin B6 helps to metabolize amino acids from our food, which are then used to make monoamine neurotransmitters like serotonin, norepinephrine, epinephrine, and even the hormone melatonin. It’s an important component for brain health. It’s so good at making you feel good, it’s even a part of many popular energy drinks [10-12].

Food sources: meat poultry, eggs, fish, bananas, berries, peaches, carrots, spinach, sunflower seeds, brown rice.

Vitamin B7 - Biotin

Biotin could be called the Beauty B Vitamin. Like all the others, it has its role in energy production – fatty acids, amino acids, and glucose metabolism. You’ll most often find it in supplements to improve hair, nail, and skin health. Actually, B7 was discovered as a solution to brittle horse hooves. The same Germans who named vitamin K for “koagulation” originally named B7 vitamin H, for Haar and Haut (hair and skin). Its role in preventing hair-loss is inconclusive, but hair health and growth are definitely improved with biotin. Beyond beauty, however, it also plays a role in brain health, supports thyroid and adrenal function, as well as building muscle [13-15]

Food Sources: liver, eggs, yeast, salmon, cheese, avocado, raspberries, cauliflower, whole grain bread.

Vitamin B9 - Folic Acid (Folate)

Also known as folate, this one has some very special considerations. In general, folate helps regulate immune,  digestive and cardiovascular health. Deficiencies have been linked to mental health problems like depression, as well as neurodegenerative conditions like Alzheimer's and dementia. Folate is also critical to the the development of the nervous system in a fetus. It is very important that pregnant mothers get enough folate, either through their diet or by supplementation.

But what’s most interesting about folate is its role in “methylation.” In this process, an enzyme abbreviated “MTHFR” takes a methyl group from one molecule and puts it on another one. Folate is necessary for that reaction. This is used to clean the cardiovascular system of homocysteine, which can cause atherosclerotic plaques.

The twist is that an estimated 20 - 30% of the world’s population carries a mutation in the MTHFR gene. It doesn’t efficiently react with folate. This puts many people in certain health risks. Because it is so inefficiently used, people with this polymorphism require much more folate.  [16-18]

Food Sources: dark green leafy vegetables, organ meats, beets, dates, avocados, beans, salmon, and bulgur.

Vitamin B12 - Cyanocobalamin

This B vitamin, also known as cobalamin, is one of the most important of the B vitamins for brain performance. Studies suggest it may actually improve memory and reverse mental fogginess. It also partners up with B9 to create the oxygen-carrying protein hemoglobin. B12 is not found in plant food sources, so vegetarians and vegans are at risk for deficiency and may want to consider supplementation [19,20]

Food Sources:beef, poultry, fish, pork, and clams.


Where are They Now?

So whatever happened to those lost B vitamins? The reclassified ones that went on to have their own careers separate from the B-Team?

B4 was always a little confused and somehow split into 3 separate compounds: choline, adenine, carnitine.

B8 was recognized as adenosine monophosphate, or AMP – a key piece in the metabolic cycle. It’s close friends call it inositol.

B10 became a sunscreen superstar known as para-amionobenzoic acid, or PABA.

The B-Team: Working Together For Optimal Health

The important thing to take away here is that the B-vitamins are not just isolated single nutrients with one function. They are each involved with different parts of the same processes.

And they work best together. They are a team.



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*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.