You’re about to find out.

Your body needs vitamins for optimal functioning, but do you know the specific purpose of each vitamin? What about the B vitamins? While vitamin B was once thought to be one distinct vitamin, further research revealed it was actually eight chemically distinct vitamins often found in the same foods. You may have seen supplements labeled as vitamin B complex. This means the vitamin contains all eight B vitamins. Individual B vitamins are referred to as vitamin B1, B2, B3, etc., but also have different names.

The B vitamins work to convert the food (carbohydrates) you eat into fuel (glucose), which gives you energy. They also help your body break down proteins and fats. To have healthy hair, skin, liver, and eyes, you need adequate amounts of water-soluble vitamin B. B vitamins also keep your nervous system and brain functioning properly. Because B vitamins are water-soluble, you need to constantly replenish your supply of vitamin B, as your body doesn’t store them.

What are each of the eight B vitamins and how do they help the body? What foods contain them and how much do you need?

B1 (Thiamine)
The fist vitamin B to be discovered was thiamine. Since it strengthens the immune system and gives the body strength in stressful conditions, it is known as the “anti-stress” vitamin. Foods that contain thiamine include whole grain pastas, cereals, and breads. Many of these foods are fortified with B vitamins since the refining process destroys thiamine. Thiamine is also naturally found in lean meats and seafood. Small amounts are also found in dairy products, fruits, vegetables, pecans, and Brazil nuts. It is recommended that men get 1.2 milligrams a day and women consume 1.1 milligrams daily of vitamin B1.

B2 (Riboflavin) 
Riboflavin boosts your energy level, immune system functioning, athletic performance, and memory. It slows aging, promotes a healthy reproductive system, helps heal burns, ulcers, liver disease, sickle cell anemia, carpal tunnel syndrome, eye problems, migraines, cervical cancer, blood disorders, acne, and muscle cramps. Riboflavin is found in foods such as meat, eggs, nuts, milk, green vegetables, and enriched flour. Men should consume 1.3 milligrams daily, women should go for 1 milligram.

B3 (Niacin)
The third of the B vitamins, niacin takes the protein from food and uses it to build new tissues and cells. It’s good for your nervous system, skin, and digestive tract, and it is used to treat high cholesterol. Sources of niacin include meat, fish, poultry, eggs, dairy, nuts, and enriched grains. Women need 14 milligrams a day, and men need 16.

B5 (Pantothenic Acid)
Pantothenic acid has many uses. It is proven to help your body use proteins, lipids, and carbohydrates and help your skin be its healthiest. Pantothenic acid is used for many other things, though not all of them are scientifically proven. These include battling allergies, alcoholism, acne, asthma, baldness, autism, yeast infections, carpal tunnel syndrome, colitis, dandruff, depression, headache, insomnia, osteoarthritis, Parkinson’s, anxiety, hypothyroidism, insect bites, and more. Pantothenic acid is found in meat, grains, legumes, vegetables, eggs, and milk. Men and women should each get 5 milligrams each day.

B6 (Pyridoxal; Pyridoxine; Pyridoxamine)
Your body needs vitamin B6 to regulate blood sugar, break down proteins, make hemoglobin (carries oxygen in the blood), make antibodies which fight disease, and for healthy nerves. You can find vitamin B6 in bananas, avocados, dried beans, nuts, meat, poultry, and whole grains. Men and women under 50 need 1.3 milligrams daily. If you’re over 50 and are a woman, you’ll need 1.5 milligrams daily, whereas men need 1.7 milligrams.

B7 (Biotin)
Biotin is a B vitamin, but is also known as vitamin H. Biotin helps to keep your skin, digestive tract, nerves, cells, and metabolism healthy. It is used for brittle nails, diabetes, and treatment of certain types of nerve diseases. Biotin is naturally found in whole grains, eggs, dairy, salmon, and chicken, and everyone should get 30 micrograms of biotin each day.

B9 (Folic Acid)
The natural form of this B vitamin found in food is called folate. The man-made form found in vitamins or fortified foods is called folic acid. This B vitamin prevents birth defects such as cleft lip, cleft palate, and spina bifida. Folate is found in citrus fruits, liver, dark green vegetables, and fortified bread, pasta, and cereal. Vitamin C helps your body absorb folate. It is recommended that men and women get 400 micrograms of folic acid daily, and pregnant or breast-feeding women need even more.

B12 (Various Cobalamins; Cyanocobalamin Supplements) This nutrient keeps nerves and blood cells healthy, helps make DNA, and works to prevent weakness and fatigue brought on by anemia. Vitamin B12 is found in beef liver, clams, fish, poultry, meat, dairy products, eggs, and fortified cereals. Adults need 2.4 micrograms per day.