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Vitamin B complex: benefits and dosage 

Your body needs eight essential B vitamins for optimal health and brain function. Explore the benefits in this guide.

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Sophie Medlin
Sophie Medlin
Head of Nutritional Research
May 11, 2020
9 min read

We all require a continuous flow of nutrients, and B vitamins are some of the most important for keeping our brains and bodies healthy.

While you can find B vitamins in many foods, Harvard Medical School warns that running low on your B vitamins can be a “sneaky” problem. Many people don’t get enough B vitamins from their food, especially if they follow a strict diet. For instance, up to 86.5% of vegetarians and vegans are low on vitamin B12, which is only found in animal-based foodstuffs.

Other people might consume the recommended B vitamins, but their bodies simply have a hard time absorbing them effectively. 

Whether you’re trying to add more B vitamins to your daily meals, or you’re trying to figure out the source of your brain fog, the following supplement guide will outline everything you need to know about B vitamins, including:

  • The eight different types of B vitamins 

  • The important roles that each B vitamin plays in your body and brain

  • How B vitamins support, enhance and strengthen your brain, your immune system and your general well-being

  • How much of each B vitamin you need every day, and how to hit those targets

  • What to look for in a B-complex vitamin supplement

Article breakdown

The functions of each B vitamin

There are eight specific B vitamins that you’ll want to focus on:

You can find all eight B vitamins in a B-complex supplement, but each vitamin has a distinct role to play:

Vitamin B benefits

You need various B vitamins for core processes like DNA formation, gene expression (the process by which your cells take action based on instructions from your DNA), and the production of blood cells. That’s how integral they are in every single process and system in your body. 

Below are just a few highlights of the vitamin B benefits to support your health.

Benefits of B vitamins on the brain 

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Benefits of B vitamins on the body 

B vitamins aren’t just good for your brain and cognitive function. They may also:

How much vitamin B complex do you need?

For optimal braincare and general wellness, aim for the following daily nutritional targets: 

  • B1 (thiamine): 1mg 

  • B2 (riboflavin): 1.3mg 

  • B3 (niacin): 16.5mg 

  • B5 (pantothenic acid): 6mg 

  • B6 (pyridoxine): 1.2-1.4mg 

  • B7 (biotin): 0.9mg 

  • B9 (folic acid): 0.2mg 

  • B12 (cobalamin): 0.002mg

Deficiency symptoms of B vitamins

If you aren’t getting enough B vitamins, you may experience B vitamin deficiency symptoms like:

  • Anaemia

  • General fatigue or a sense of tiredness

  • Confusion, lack of concentration, poor memory, and other cognitive problems

  • Higher levels of stress and anxiety

  • Lower moods, such as depression or sadness

  • Lower immune system strength (often manifesting as getting sick more often)

  • Gastrointestinal concerns, such as bowel issues or cramping

  • Skin rashes, dry skin, or brittle nails and hair

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Food sources for B vitamins

With the exception of vitamin B12, most B vitamins can be found in plant-based foods or fortified cereals and beverages.

Some of the best foods to add to your diet if you want to boost your intake of B vitamins include:

  • B1 (thiamine): citrus fruits, whole grains, liver and pork

  • B2 (riboflavin): dairy, eggs, leafy greens, and almonds

  • B3 (niacin): fatty fish, peanuts, avocado, and poultry

  • B5 (pantothenic acid): fatty fish, sweet potatoes, dairy and organ meats 

  • B6 (pyridoxine): oats, bananas, peanuts, dairy and fish

  • B7 (biotin): leafy greens, peas, legumes, nuts and seeds, and salmon

  • B9 (folic acid): leafy greens, apples, corn, and many types of seafood

  • B12 (cobalamin): organ meats, beef, salmon, and fortified foods

Vitamin B complex supplements

If you aren’t getting enough of each B vitamin, or if you’re experiencing symptoms of a B-vitamin deficiency, consider taking a B-complex supplement. As its name suggests, a B-complex product provides all of the essential B vitamins you need without requiring you to take eight different supplements. 

For example, the Heights Smart Supplement provides all eight B vitamins along with 12 other essential nutrients. Most importantly, our nutritional team and in-house medical experts formulated it with large enough quantities to help compensate for the fact that many people’s bodies struggle to absorb B vitamins efficiently. By safely increasing your dosage with the Smart Supplement, you can be confident that you’re providing your body with everything that it needs.

What other vitamins and minerals should I take with B vitamins?

Some supplements block the absorption of other nutrients, while others do the opposite and actually improve a specific nutrient's bioavailability. The Smart Supplement contains specific compounds chosen for maximum absorption, and the capsule itself also ensures that none of the B vitamins are wasted.

And don’t forget the importance of timing timing. Because B vitamins can be energising, take your B-complex vitamins in the morning to give yourself a physical and mental boost all day long.

FAQ about vitamin B supplements 

1. What are vitamin B-complex supplements for?

B-complex vitamins protect the healthy functioning of your brain and body by:

  • Generating new red blood cells that carry nutrients and oxygen throughout your body

  • Lowering your homocysteine levels, which protects your blood vessels, your organs, your brain and other important systems

  • Supporting the production of neurotransmitters

  • Contributing to all cellular processes

2. Do vitamin B-complex supplements work?

Numerous studies support the effective use of B vitamin supplementation. For example, patients with Alzheimer’s disease who took a B-complex supplement saw improvements in their cognitive function.

3. Who should take a vitamin B-complex supplement?

Anyone who wants to proactively support their health from the cellular level on up will benefit from taking B vitamin supplements. 

B-complex supplements may also be especially beneficial to people who are more prone to experience a B-vitamin deficiency, including:

  • Older people over the age of 50

  • Individuals who are pregnant or breastfeeding 

  • Those on a strict diet that eliminates entire food groups, including those who are vegan, vegetarian, or keto

  • People who have a pre-existing health condition, such as Crohn’s disease, HIV, kidney health conditions, or alcohol use disorder.

4. Is taking a B-complex supplement safe?

B vitamins are water-soluble, meaning your body flushes it out of your system when it has used up all the B vitamins it needs in a day. Research shows that most B vitamins are safe in high doses, with potential health drawbacks if you consistently take extremely large doses of B3, B6 or B9.

5. Can you overdose on a B-complex supplement?

Because B vitamins are water-soluble, you can’t overdose on B vitamins the way you would with a fat-soluble vitamin.

6. What are vitamin B-complex side effects?

Some people experience rare side effects of consuming too much of a specific vitamin B. Some side effects may include:

  • Increased urination

  • Excessive thirst

  • Nausea, cramping and gastrointestinal discomfort

  • Blurry vision

  • Skin conditions

How we use B vitamins in Heights' Smart Supplement 

At Heights, we've formulated the Smart Supplement with the most bioavailable forms of each B vitamin possible. 

Best of all:

  • Each daily dose contains all eight B vitamins necessary for optimal brain health and cognition. 

  • Each B vitamin is pure and quality-tested.

  • Everything is manufactured in small batches so you can rest assured that your B-complex supplementation is safe and effective.

  • It meets many common dietary and lifestyle practices: It's gluten-free, 100% plant-based, allergen-free and contains absolutely zero GMOs, contaminants, fillers or colourants.

Find out why the Smart Supplement is the highest rated in the world, and how it helps to keep you feeling better, every day.

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Here's a handful of relevant scientific studies on B-complex supplementation:

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