The vitamin B complex: Why are the B vitamins important to athletes, and should you supplement?

Sports nutritionist Stephen Smith explains all you need to know about the different B vitamins and when, or whether, athletes should supplement

Published: March 12, 2020 at 11:14 am

What is vitamin B?

The B vitamins are a group (known as the vitamin B complex) of water-soluble compounds and include: B1 (thiamine); B2 (riboflavin); B3 (niacin); B5 (pantothenic acid); B6 (pyridoxine); B7 (biotin); B9 (folic acid); and B12 (cobalamin).

What is the vitamin B complex responsible for?

Representing such a large group of compounds, the Vitamin B complex plays a part in a large number of bodily functions. For example, thiamine (B1), helps release energy from food while others (B2, B6, B9 and B12) play an important role in maintaining blood health through iron metabolism and red blood cell production. Other functions of the vitamin B complex include promoting cell health, brain function, healthy digestion, nerve function and cardiovascular health.

Why are the B vitamins important for athletes?

While it’s important to make sure you’re meeting the daily requirements for the whole group of B vitamins due to the large number of roles they play, thiamine, riboflavin, and B12 are particularly important in producing energy from food and red blood cells. These are obviously important processes for athletes, as we need energy to fuel and recover from workouts, as well as have sufficient blood cells to carry oxygen to the working muscles.

How much vitamin B do athletes need?

The recommended intakes range from 1.5 micrograms (mcg) for B12 to around 16.5 milligrams (mg) for B3. Being such small amounts, it’s not really necessary for athletes to worry about aiming for specific numbers. Most athletes will be able to meet these recommended doses by following a wide and varied diet.

Which foods are rich in B vitamins?

A wide range of foods contain B vitamins, particularly fruits and vegetables. A phrase I like to use is ‘eat your rainbow’, which means you should always try and include a mix of colours on your plate. Although, some meat, fish, dairy and animal products are also important for meeting your B vitamin needs, such as eggs for riboflavin, tuna and salmon for niacin, and beef, fish and shellfish for B12. You'll also find some foods, particularly breakfast cereals, fortified with B12.

Should you take a vitamin B supplement?

If you're eating plenty of fruit and vegetables, and different sources of animal products, supplementation isn’t necessary. However, there are times where you may want to include a multi-vitamin which meets or exceeds the recommended daily intake of B vitamins, e.g. if you're trying to lose weight (as your overall food intake may be reduced), or blocks of high training volume where you're expending large amounts of energy over several weeks.

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