When we think about diet, we tend to focus on macronutrients – carbohydrates, fats and protein. But vitamins and minerals, the micronutrients, are just as essential. Even when vitamins do come to mind, it's usually immune-boosting vitamin C or the "sunshine vitamin," vitamin D, that get the attention. The B vitamins tend to be overlooked – but without them, health would suffer significantly.
Here's a full breakdown of the B vitamins: what they do, where to find them, and what a deficiency can look like.
The What, Where and Why of the B Vitamins
The B vitamins (along with vitamin C) are water-soluble, meaning the body can't store them the way it stores fat-soluble vitamins A, D, E and K. Any excess is eliminated through urine rather than stored for later, which is why regular daily intake matters.
There are eight B vitamins in total, each with a specific role, but collectively they're associated with releasing energy from food, preventing fatigue, and supporting the nervous system. They're commonly found in wholegrain bread, cereals, pasta, brown rice, leafy greens, nuts and pulses. Here's a closer look at each one:
Vitamin B1 – Thiamine
Role: Releases energy from carbohydrates, supports cell growth and development, and helps the immune system, heart and skeletal muscles.
Good sources: Wholegrains, nuts, fresh and dried fruit, fortified cereals and bread.
Deficiency symptoms: Weight loss, muscle weakness, confusion, short-term memory issues.
Vitamin B2 – Riboflavin
Role: Releases energy from fats, proteins and carbohydrates; transports iron; supports the skin, mucous membranes and nervous system.
Good sources: Milk, eggs, brown rice, fortified cereals, beans, mushrooms, green vegetables.
Deficiency symptoms: Dry, cracked skin around the mouth and nose; a sore, red tongue; hair loss; itchy or sore eyes.
Vitamin B3 – Niacin
Role: Releases energy from food; supports healthy skin and immune function.
Good sources: Meat, fish, fortified bread, eggs, dairy.
Deficiency symptoms: Rare, but severe deficiency can cause pellagra, which makes skin extremely sensitive to sunlight.
Vitamin B5 – Pantothenic Acid
Role: Releases energy from food.
Good sources: Meat, eggs, wholegrains, fortified cereals, tomatoes, broccoli, potatoes.
Deficiency symptoms: Extremely rare.
Vitamin B6 – Pyridoxine
Role: Releases energy from carbohydrates and protein; supports haemoglobin formation and amino acid production.
Good sources: Poultry, white fish, eggs, fortified bread and cereals, wholegrains, soya, dairy, potatoes.
Deficiency symptoms: Anaemia, cracked mouth corners, swollen tongue, confusion, low mood.
If you're looking to boost your B6 intake through diet specifically, our guide to foods high in vitamin B6 covers this in more detail.
Vitamin B7 – Biotin
Role: Breaks down dietary fats.
Good sources: Meat, fish, nuts, seeds, fortified cereals, sweet potatoes.
Deficiency symptoms: Extremely rare.
Vitamin B9 – Folic Acid
Role: Supports formation of healthy red blood cells and nervous system cells.
Good sources: Fortified cereals, brown rice, chickpeas, Brussels sprouts, broccoli, spinach, peas, oranges, bananas.
Deficiency symptoms: Anaemia, tiredness, low mood, insomnia. Deficiency during pregnancy is linked to spina bifida risk, which is why folic acid supplementation is recommended during the first trimester – our folic acid gummies are one option worth considering if advised by your GP or midwife.
Vitamin B12 – Cobalamin
Role: Releases energy from food; supports red blood cell production and the nervous system.
Good sources: Meat, fish, eggs, dairy, fortified cereals, Marmite.
Deficiency symptoms: Anaemia, tiredness, abdominal pain, a swollen or burning tongue. B12 deficiency is particularly common among vegans and vegetarians, since it's primarily found in animal products – see our vegan B12 food sources guide if this applies to you. If you suspect a deficiency, a B12 blood test can confirm your levels.
Overall, B vitamin deficiencies are relatively rare in a varied diet, but they can occur and typically present as tiredness and low energy. Eating a wide range of wholegrains, vegetables and fortified foods covers most needs – if you suspect a deficiency, particularly if you don't eat red meat or animal products, a B complex supplement is worth considering alongside dietary changes.
