What is vitamin B?

Vitamin B is a group of vitamins that help your body’s metabolism function better. The B group of vitamins include thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate (B9) and cobalamin (B12).

The ‘B-group’ or ‘B-complex’ of vitamins make up 8 out of 13 essential vitamins and are all water-soluble (dissolves in water). This means that they cannot be stored in the body and must be consumed regularly as part of a healthy diet.

Why is vitamin B important for your health?

Vitamin B is considered an essential vitamin. Your body needs it to work properly, including for many different cellular processes, such as building DNA components and proteins.

Each of the B-group vitamins plays a critical role in keeping you healthy. For example, B12, B6 and B9 are important vitamins for healthy brain and nerve function, while vitamin B2 is important for skin health and good vision.

What are the natural sources of vitamin B?

Vitamin B is naturally found in animal-based products, such as chicken, fish, meats and dairy products. Other natural sources of vitamin B include wholewheat bread, green leafy vegetables, nuts and yeast.

Some B vitamins are added to food. For example, vitamin B9 is added to wheat flour used in bread, and B12 is added to plant-based vegetarian meat alternatives.

Because many proteins contain vitamin B, watch your protein intake. Australian Dietary Guidelines recommend the following:

• Female adults should eat 2 to 2.5 serves of protein daily.
• Male adults should eat 2.5 to 3 serves of protein daily.

On average, each of the following is 1 serve:

• 65 grams lean red meat
• 80 grams salmon
• 100 grams tuna
• 170 grams tofu
• 1 cup baked beans and other legumes
• 2 eggs

Go here for more information on foods high in vitamin B.

Should I take vitamin supplements?

Some people may not get enough vitamin B in their diet, including those on a restrictive diet (such as vegans) or a specific diet due to a health condition. Others may not be able to properly absorb B vitamins due to illness or after gastrointestinal surgery.

The Australian Dietary Guidelines recommend that people with a vegan diet take a B12 supplement, since deficiency is more common in this group of people.

If you are planning pregnancy, take a vitamin B9 (folate) supplement at least 1 month before conception and for the first trimester of pregnancy to help prevent foetal neural tube defects.

Before taking any vitamin supplement, speak with your doctor or an accredited dietitian. While vitamins can supplement your diet, you should still eat healthily.

What is the recommended dosage for vitamin B supplements?

Many over-the-counter multivitamins include B vitamins. Each type of vitamin B has its own dosage. The recommended dose of a specific vitamin B may depend on your life stage — for example, pregnant people, breastfeeding people, older adults and children all need different doses of each individual vitamin B.

If you use over-the counter supplements, choose the supplement that suits your life stage and circumstance, and always read the doses on the bottle. Do not double up on supplements without first speaking with your doctor, dietitian or pharmacist — for example, if you take a multivitamin, check before you take a specific vitamin B supplement.

People with general vitamin B deficiency may be prescribed a 2mL vitamin B injection by their doctor.

Can taking vitamin B supplements cause side effects?

Vitamin supplements can interact with other medications. It is important to speak to your healthcare professional before taking supplements or starting a new prescription medicine.

If you have received the vitamin B injection, there is a small chance you may have a side effect such as nausea, headache, fatigue or hives.

Can I take too much vitamin B?

Vitamin B12, like other B-group vitamins, is water-soluble. This means that in most cases, the extra vitamin B in your body will pass naturally out of the body. However, there are some cases where toxicity can occur. For example, if you take too much B6, it can result in nerve damage.

The best way for healthy people to avoid taking too many supplements is by eating enough vitamin B in natural food sources. Most people can get enough vitamin B by eating a range of healthy fresh foods.

If you are concerned that you have taken too much of a vitamin B supplement, call the Poisons Information Centre (13 11 26) immediately.