But there are many more, little-known reasons why it boosts our health.
For example, vitamin B6 can help the body manufacture neurotransmitters (brain chemicals that communicate information throughout our brain and body) such as serotonin. This helps the body to cope depression, stress and anxiety.
Meanwhile, a lack of vitamin B2 gives us those unsightly cracks around the mouth and a shortage of B7 can lead to brittle hair and nails.
The good news? Most of us get more than vitamin B through our diet - many cereals, for example, are fortified with it, and it's found in a wide variety of foods.
The bad? Our hectic, stress-filled lifestyles - coupled with a sugary, white-carb and booze-filled diet (something many of us are guilty of) - can deplete our reserves of this vital vitamin.
In addition, the body cannot store B vitamins, so they must be replenished every day (the exception is B12, which can be stored in the liver).
In short, this could be the reason you're suffering from a number of ailments (see below for a detailed breakdown) or general lethargy.
WHAT ARE B VITAMINS?
Unlike other types of vitamin, there are various "sub-types" of B vitamins.
These eight vitamins make up what's known as the B complex group.
Specifically, this is comprised of: Thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate (B9) and cobalamin (B12).
HOW ARE B VITAMINS DEPLETED?
A sugary or high carb diet:
A diet that is high in sugar and white carbohydrate foods (e.g. White bread, white pasta) can take its toll on the B vitamins.
Not only that, alcohol also stops b vitamins from being absorbed by the body, so there's a double-whammy effect.
Stress:
B vitamins play a key role in the maintenance of a healthy nervous system.
While a little stress is common in day-to-day life, excessive stress can put a burden on the body's requirement for B vitamins - it needs more to manufacture neurotransmitters to keep our mood stable.
Stress can also impact on our diet, leading to us skip meals and/or choose foods of poor nutritional quality, which in turn may reduce the number of B vitamins we take in.
Why you need it: This vitamin is required for the break down and release of energy from food. You also need it to maintain a healthy nervous system - vital to prevent low mood.
Signs of deficiency: Tiredness, loss of concentration, irritability, headache, loss of appetite, nausea, constipation
How to eat it: Asparagus, peas, sunflower seeds, green peas, trout, macadamia nuts, pistachio nuts, acorn squash, soy beans, black beans, navy beans
B2 - riboflavin:
Eggs and spinach contain a lot of B vitamins including B12, biotin, B2 and B5. Photo / Getty Images
Why you need it: Required for keeping your skin and eyes healthy as well as maintaining a healthy nervous system and converting the food you eat into energy.
Signs of deficiency: Mouth ulcers, sores and cracks at the corner of the mouth (angular cheilosis), tired, sensitive, gritty, blood-shot eyes, sensitivity to bright light, sore throat and tongue, itching, scaly eczema-like skin rash - especially on the face and nose, insomnia
How to eat it: Mushrooms, eggs, spinach, broccoli, asparagus, almonds, cheese, mackerel, squid, sesame seeds
B3 - niacin:
Chicken is a good source of protein and contains B3, B5, B6 and B12 vitamins. Photo / Getty Images
Why you need it: Research published yesterday revealed it could play a crucial role in plugging a nutrient deficiency that can stop babies' organs developing correctly.
It's also required to convert food into energy, helps to ward off tiredness and fatigue and keeps our mood stable.
Signs of deficiency: Tiredness, feeling weak, loss of appetite, controlled blood sugar and/or cholesterol, headache, nausea
How to eat it: Tuna, chicken, turkey, mushrooms, sea vegetables, peanuts, peas, sunflower seeds, avocados
B5 - pantothenic acid:
Why you need it: So that the body can make and metabolise vitamin D - important for healthy bones, respiratory health (your heart and lungs) and a strong immune system.
B5 also helps to convert food into energy.
Signs of deficiency: Feeling tired, weak and/or unable to deal with stress, indigestion, insomnia, loss of appetite.
How to eat it: Liver, sunflower seeds, salmon, avocados, broccoli, mushrooms, oats.
B6 - pyridoxine:
Banana contains B vitamins such as B6 and biotin. Photo / Getty Images
Why you need it: It helps the body manufacture neurotransmitters, such as serotonin, which aids in the body's ability to cope with depression, stress and anxiety.
Vitamin B6 may also help boost the immune system during times of anxiety.
In fact, and research also shown B6 supplements may prove helpful in relieving the emotional symptoms associated with PMS.
Not only that, it's essential in the formation of hemoglobin, which is the substance in red blood cells that carries oxygen around the body.
Signs of deficiency: Greasy rash on the forehead and around the nose, low sex drive, irritability, anxiety, depression, headache.
Salmon is an excellent source of B12 and other B vitamins. Photo / Getty Images
Why you need it: Biotin is required to help the body to break down fat and is important for healthy hair, nails and skin.
Signs of deficiency: Dry, scaly, flaky skin; rash around the eyes, nose and mouth; brittle hair and nails; tiredness/lethargy; withdrawn behaviour; loss of appetite.
How to eat it: This vitamin is found in a wide variety of foods but in very small amounts. Eat eggs, cheese, dairy, liver, avocado, raspberries, bananas, nut butters, salmon, sardines.
B9 - folic acid:
Mango and oranges contain folates and vitamins such as B6. Photo / Getty Images
Why you need it: Important during the first three months of pregnancy to reduce the risk of neural tube defects such as spina bifida.
Pregnant women are advised to supplement their diet with 400mcg of folic acid up until the 12th week of their pregnancy.
This B vitamin has also been shown to help breakdown an amino acid called homocysteine in the blood.
An excess of this has been linked with an increased risk of coronary heart disease, stroke and peripheral vascular disease.
Signs of deficiency: Red, sore tongue; cracking at the corners of the mouth; tiredness/weakness; irritability; forgetfulness/confusion; insomnia; anaemia; muscular cramps; depression; dementia.
How to eat it: Black-eyed peas, lentils, spinach, asparagus, lettuce, avocado, broccoli, mango, oranges.
B12 - cobalamin:
Shellfish such as crab is a good source of B12. Photo / Getty Images
Why you need it: To produce healthy red blood cells and protect cells from the damage caused by excess free radicals.
Also required to maintain a healthy nervous and immune system.
Signs of deficiency: Sore tongue; tiredness/exhaustion; menstrual disorders; reduced immunity; pernicious anaemia (where not enough red blood cells are present due to a lack of vitamin B12)
How to eat it: Shellfish, liver, mackerel, crab, tofu, red meat, milk, cheese, eggs. As a result, B12 may be difficult to glean from a vegan diet.
HOW TO BOOST YOUR VITAMIN B INTAKE:
Certain foods are clearly richer in B vitamins than others. Including these foods in your daily diet can help to maintain your intake of B vitamins.
Breakfast
• Boiled eggs on wholegrain toast • Greek yogurt with nuts, seeds and berries • Smoked salmon and scrambled egg • Fortified breakfast cereal with milk and chopped banana
