There are eight B vitamins, each with their own unique properties and recommended amounts. That can be a lot to remember when choosing which supplements to include, let alone which foods to put in your next meal—which is probably why many people end up looking into a B Complex Vitamin. But what is the best B complex vitamin to take? Why isn’t just one vitamin B enough? What is vitamin B good for? We’ve got the answers to that and more when it comes to the benefits of vitamin B complex.
Take our quiz and find out which vitamins and supplements best support your lifestyle and nutritional needs. Also see our blog for more nutritional resources and to answer questions like, why do we need vitamins?
What Are B Vitamins Good For?
There are eight B vitamins: Thiamin (Vitamin B1), Riboflavin (Vitamin B2), Niacin (Vitamin B3), Pantothenic Acid (Vitamin B5), Vitamin B6 (Pyridoxine), Biotin (Vitamin B7), Folate (Folic Acid, Vitamin B9) and Vitamin B12 (Cobalamin). Scientists have grouped the eight B vitamins together as a “complex” because they share three major similarities: they’re water-soluble, act as coenzymes (helper molecules for biochemical reactions), and most are involved in cellular energy processes. Beyond their shared traits, however, every B vitamin serves a unique role in the body and should be considered separately to support a healthy diet and overall health .
Here’s a quick overview of what makes each B vitamin a unique and essential vitamin, what their RDAs are, and where to find them in food—because the best source of nutrients always starts with your diet.
Thiamin (Vitamin B1) helps break down carbohydrates
Thiamin is involved in several functions in the metabolism of carbohydrates, certain amino acids, and fatty acids.1 Like all vitamin Bs, Thiamin helps break down the food you eat into the energy you need.2 Thiamine also plays an integral role in the brain and central nervous system.1
Women ages 19 years and older should consume 1.1 mg / day, and men ages 19 years and older should consume 1.2 mg / day.2 Thiamin is found in many foods (fortified or not), including lentils, peas, long-grain brown and white rice, pork, spinach, and even cantaloupes.1
Riboflavin (Vitamin B2) supports antioxidants3
Riboflavin not only helps convert food into cellular energy, but it also helps several antioxidants neutralize free radicals. Free radicals are those pesky unstable molecules we generate when the body is under various everyday stresses, and that can cause a lot of problems if left alone.
Women ages 19 years and older should consume 1.1 mg / day of Riboflavin, and men ages 19 and older should consume 1.3 mg / day.4 Riboflavin is found in various foods including fortified cereals and breads, milk, almonds, salmon, chicken, broccoli, spinach, and even asparagus.5
Niacin (Vitamin B3) supports over 400 metabolic pathways6
Let’s talk turkey. Tryptophan, that amino acid in turkey that makes you sleepy? Your body can turn some of that into Niacin. And it wants to because Niacin supports over 400 metabolic pathways—more than any other B vitamin. Its roles stretch from cellular energy production to helping with DNA replication.6
Women ages 19 years and older should consume 14 mg / day of Niacin, and men ages 19 years and older should consume 16 mg / day.7 Niacin is found in chicken, turkey, salmon, beef, peanuts, pasta, lentils, lima beans, and even coffee.8
Pantothenic Acid (Vitamin B5) helps make and break down fats9
Like all the other B vitamins, pantothenic acid helps convert food into usable energy. But its unique traits are that it also helps make and break down fats, make neurotransmitters (brain chemical messengers), and assists in the synthesis of important hormones like melatonin.10
Adults ages 19 years and older should consume 5 mg / day of Pantothenic Acid.10 Pantothenic acid can be found in sunflower seeds, yogurt, avocado, sweet potatoes, milk, and pork.10
Vitamin B6 (Pyridoxine) helps process protein
Like we said, B vitamins play a role in cellular energy production and B6 is no exception. This vitamin is essential to over 100 reactions in the body, most of which are involved in protein metabolism.11,12 Vitamin B6 plays a unique role in helping make neurotransmitters like serotonin and dopamine that play an important role in regulating mood.12
Adults ages 19–50 years should consume 1.3 mg / day of Vitamin B6. Women age 51 and older should consume 1.5 mg / day, and men should consume 1.7 mg / day.11 Vitamin B6 can be found in many foods, including fortified cereals, salmon, turkey, avocado, chicken, spinach, and bananas.11
Biotin (Vitamin B7) helps make glucose13
Biotin helps make sure our body has enough of the most critical cellular energy ingredient available to function—glucose.13 You’ve probably heard of glucose before, and while yes—glucose is a simple sugar, it’s a necessary sugar that bodies and brains need as fuel.
Adults ages 19 and older should consume 30 mcg / day of Biotin. Thankfully, this vitamin is found in many foods, including egg, salmon, avocado, pork, cauliflower, and even raspberries.14
Folate (Folic Acid, Vitamin B9) is needed to make DNA15
Vitamin B9 is an essential nutrient for those building blocks of life we call DNA.15 While Folate is essential for brain development and function at all ages, it’s best known for its critical role in the proper development of fetal nervous systems and to help prevent neural tube defects.
Adults ages 19 and older should consume 400 mcg Folate/ day.15 Many green leafy vegetables contain rich amounts of Folate, but you can also find it in lentils, garbanzo beans, asparagus, spinach, and even orange juice.16
Vitamin B12 (Cobalamin) helps keep nerve and red blood cells healthy
Vitamin B12 is widely known for its role in energy processes. Not only does it help transform the food we eat into cellular energy, but it also helps make the red blood cells that carry oxygen that is needed to carry out these high energy processes. Vitamin B12 teams up with Folate (and Vitamin B6) to drive some of the most important functions in the body, from making DNA to supporting a healthy brain and nervous system.17
Adults 50 years and under should consume 2.4 mcg / day of Vitamin B12. This vitamin is mostly found in animal byproducts, such as beef, salmon, milk, turkey, brie, chicken, and egg.17 For adults over 50 years, experts recommend a dietary supplement of 100 to 400 mcg/day of vitamin B12 due to age-related decline in absorption.17
There’s a reason why some of the first vitamin B deficiency symptoms appear to be low mood, stress, and mental or physical fatigue.18,19,20 Your brain and nervous systems must get enough of these crucial B vitamins to function.19,20
Here are the specific roles of key B vitamins that help support brain health:19
Supports neurotransmitters (Thiamin, Biotin, Vitamin B6, Folate, and Vitamin B12)
Neurotransmitters are the brain’s signaling molecules which help regulate mood.
Supports energy metabolism (Thiamin, Riboflavin, Niacin, Vitamin B6, and Vitamin B12)
Energy metabolism is how the body turns food into fuel, which helps power almost everything in the body, including your brain.
Supports oxygen transport (Folate, Vitamin B6, and Vitamin B12)
These B vitamins help make red blood cells, which carry the hemoglobin that transports oxygen and nutrients to the organs, including your brain.
Supports DNA biological processes (Folate and Vitamin B12)
Folate is a key driver of gene regulation that is essential for healthy brain function.
B Vitamins For Cellular Energy20
The B vitamins for cellular energy include every B vitamin (except Folate).20 So, if you’re looking to for cellular energy support, make sure either your diet or your vitamin B complex includes the RDAs for the following B vitamins:20
Thiamin (Vitamin B1)
Riboflavin (Vitamin B2)
Niacin (Vitamin B3)
Pantothenic Acid (Vitamin B5)
Vitamin B6 (Pyridoxine)
Biotin (Vitamin B7)
Vitamin B12 (Cobalamin)
We say “cellular energy” because your body can’t directly use the energy in the form that is stored in the foods you eat. It must be converted first into a specific type of energy that can be used by the body aka cellular energy. But this conversion can’t happen until something comes along and kicks it into gear. That’s where the B vitamins come in. B vitamins help transform the stored energy in the foods we eat into active energy that drives our cells to function.20
Why Some Women Take Vitamin B6 For Nausea During Pregnancy
If you’re suffering from nausea and vomiting during early pregnancy, you’re not alone.12 Morning sickness can affect up to 85% of women during early pregnancy and can last anywhere from 12–16 weeks.12 The exact cause of this is still unknown, but Vitamin B6 has long been used for helping with nausea.12
Even today, according to the American College of Obstetricians and Gynecologists and American Academy Family Physician, Vitamin B6 is a good “first-line” choice for nausea and vomiting during pregnancy.21, 22 The dosing for vitamin B6 for morning sickness is higher than what’s found in a prenatal vitamin, so it’s always important to work with your health care provider.
Generally speaking, it’s recommended women consume 1.8 mg / day of Vitamin B6 while pregnant.12 Vitamin B6 can be found in a variety of foods, including, fortified breakfast cereals, salmon, russet potatoes, avocado, spinach, bananas.12
Why Folate (Vitamin B9) Is Found In So Many Prenatal Vitamins
Folate, as its synthetic form Folic Acid, is often found in many prenatal vitamins and for good reason. Developing fetuses need Folate to form new cells, tissues, and organs in both the brain and spine.23 Supplementing with Folate or Folic Acid can help prevent brain and spinal birth defects.24
Women who are pregnant (or looking to become pregnant) are recommended to supplement with 400–800 mcg / day of Folic Acid.24,25,21 That’s 680–1360 mcg / day of Folate DFE (Dietary Folate Equivalents). Folate can be found in many foods, including spinach, asparagus, lentils, lima beans, and citrus fruit juices. Folic acid can be found in some fortified foods.
Why Vegans And Vegetarians Should Pay Special Attention To Vitamin B12
Vitamin B12 is essential for everyone, no matter what their diet is. But because Vitamin B12 is found predominantly in animal byproducts, vegans and vegetarians can particularly be at risk of a Vitamin B12 gap or even a deficiency. This is why it’s often recommended anyone following a diet which restricts those foods should supplement with Vitamin B12.
What About Vitamin B Yellow Pee Side Effects?
Yellow pee is a common and harmless side effect of taking Riboflavin (Vitamin B2), which is often found in a Vitamin B Complex.5 In fact, the term “flavin” comes from the Latin term “flavus,” which means "yellow."
Why Booze Is Bad For Your B Vitamin Intake
It’s probably no surprise that alcohol has a negative effect on how well your body uses B vitamins.4,7,11,15 Chronic alcohol intake can affect how well the body absorbs and uses B vitamins, specifically Thiamin, Niacin, Vitamin B6, and Folate.4,7,11,15 Although having a drink every once in a while probably won’t have an effect, drinking on a consistent basis for even a few weeks may impact B vitamin status. These vitamins are called “essential” for a reason. Any missing amounts over any length of time will have an effect on our physical and psychological health.4,7,11,15
So, What Is The Best B Complex Vitamin To Take?
The best B complex vitamins contain at least the recommended dietary allowances (RDAs) for all of the eight B vitamins and are vetted by third-party organizations.
You can find RDAs listed on the supplement labels as the Daily Value. You can also usually find if the supplement was vetted by a third-party organization, such as US Pharmacopeia (USP), by looking on its label or the product’s website. These third-party organizations often check for things like purity, strength, and composition. Because these organizations don’t have a stake in whether the product sells or not, they’re able to be more objective when it comes to the purity and quality of your vitamins.
What Is The Best Time To Take Vitamin B Complex?
B vitamins are water-soluble and easily absorbed, so generally, you don’t need to take them with food to help with absorption. However, it’s best to take all your vitamin supplements with meals to reduce the chance of stomach upset, ensure absorption of other key nutrients, and make sure you’re getting the most out of your dietary supplements
Consistency is key. Generally speaking, the B vitamins should be consumed on a regular basis because the body doesn’t have long-term storage for water-soluble vitamins. Deficiencies of B vitamins can develop quickly, so pay attention that you are meeting your daily B vitamin requirements.26
Be Confident In Your B Vitamin Complex
As you can tell, the answers to questions like “what is vitamin B good for” or “what is the best B complex vitamin to take” are as varied as the roles of the individual B vitamins themselves. Ultimately, the B vitamins are essential nutrients, meaning your body needs adequate intake to sustain its basic everyday functions and, as such—sustain yours. The best B complex Vitamin will reflect this by offering all eight of the B vitamins in their respective RDA quantities, while also having undergone strict manufacturing processes.
Now you’re armed with all the details about which specific B vitamins to look out for if you want your vitamin B complex supplement a bit to address your specific needs.
This information is for educational purposes and is not medical advice or intended as a recommendation of any specific products. Consult your health care provider for more information.
Corrie became a nutritional nerd the second she learned about trans fats in college. Ever since then, she’s been trying to figure out easy life hacks for staying healthy without making her entire world about workouts and kale. She’s dedicated the last few years of her career to writing fun, educational content to help make good nutrition a little less boring and a little more accessible to non-scientists like herself. When she’s not scrolling through new research on gut health, you can find her playing Magic the Gathering or tending to her many (somehow still living) plants.
Carroll is a nutrition scientist and communicator with over 25 years of experience as a clinician, researcher, and educator at major universities, medical centers, and nutrition industry settings. She is a passionate advocate of nutritional health and established the nutrition education and science platforms at Pharmavite. Carroll is an expert in personalized nutrition and has published several scientific papers on vitamin and mineral inadequacies and the impact on health and wellbeing. Prior to joining Pharmavite, Carroll taught nutrition at UCLA Medical School and Santa Monica College and was a chief clinical dietitian and researcher.