Vitamins form a group of organic compounds that the body needs in small quantities, and it is characterized by its ability to be soluble either in water or fat, and it is easy for the body to store fat- soluble vitamins compared to those dissolved in water, and at the present time there are about 13 known vitamins, and food is the main source To obtain these vitamins, but in some special cases a person may be advised by a doctor to take nutritional supplements. 
The importance of vitamins
Vitamins do not have a specific function. Rather, their importance stems from the fact that each vitamin has a special function that it performs to avoid a decrease in its levels in the human body and thus exposure to health problems, for example, maintaining normal levels of vitamin C helps to avoid anemia, Also, maintaining the normal level of vitamin A protects against night blindness, and the rise in vitamin levels above normal levels as a result of excessive consumption may result in some health problems. 
Sources of vitamins
Various vitamins can be obtained from multiple sources as follows: 
- Vitamin B1: It is present in all food sources in moderate quantities.
- Vitamin B2: found in dairy products, milk, green leafy vegetables, fortified breads, and whole grains.
- Vitamin B3: Meat of all kinds, including poultry and fish, vegetables, fortified breads, cereals, and peanut butter.
- Vitamin B6: meats of all kinds, in addition to vegetables and fruits.
- Vitamin B12: It is not found in plant foods, but is found in all kinds of meat in addition to seafood, dairy products, and eggs.
- Vitamin A: eggs, fortified milk, cheese, cream, margarine, and liver, as well as dark green vegetables, apricots, cantaloupe, carrots, sweet potatoes and squash.
- Vitamin D: Available in the liver, egg yolks, ghee, milk, fatty fish, and sunlight also helps the skin to form vitamin D when exposed to it.
- Vitamin K: It is found in green leafy vegetables, vegetables of the cabbage family, and milk, and is also produced by gut bacteria.
- Vitamin E: green leafy vegetables, wheat seeds, unsaturated vegetable oils, liver, egg yolks, and nuts.
- Vitamin C: It is found in citrus fruits such as oranges, kiwi, strawberries, papaya, cantaloupe, and vegetables such as those belonging to the cabbage family, tomatoes, potatoes, and peppers.
- Biotin: It is found in many types of foods, in addition to being produced in the intestine by bacteria.
- Folic acid: It is found in green leafy vegetables, legumes, seeds, orange juice, and liver, in addition to being included in most refined grains.
- Pantothenic acid: widely found in foods.
- Christian Nordqvist (26-9-2017), "Vitamins: What are they and what do they do?" , Www.medicalnewstoday.com The , Retrieved 3-1-2018. Edited.
- "Vitamins" , www.medlineplus.gov , 4-10-2017, Retrieved 3-1-2018. Edited.
- "Vitamins: Their Functions and Sources-Topic Overview" , www.webmd.com , Retrieved 3-1-2018. Edited.