"Drink the juice quickly because the vitamins are gone." How many times have we heard this phrase, especially from our mother's mouth, as if vitamins could run out of a glass of freshly squeezed juice. No, vitamins do not run away anywhere while they are in the glass, but... what are vitamins so that, since we were little, we have been told that they are so important?
Vitamins are essential micronutrients for cell function, growth and development of the body, they are obtained through the food we eat daily, hence the importance of a balanced, healthy and complete diet. There are 13 essential vitamins: Vitamin A or retinol, vitamin B, vitamin C, vitamin D, vitamin K, vitamin B1 or thiamine, B2 or riboflavin, B3 or niacin, B5 or pantotheic acid, B6 or pyridoxine, B7 or biotin, B9 or folic acid, and vitamin B12 or cyanocobalamin. Each of the 13 vitamins fulfills a certain function in the body and its deficiency can cause health problems.
Vitamins are grouped into two categories based on their solubility: water-soluble vitamins and fat-soluble vitamins.
Fat-soluble vitamins are those that can be dissolved in fats. They are obtained through foods such as beef, oily fish, eggs, liver, fruits and red and green leafy vegetables. The body easily absorbs them thanks to the fat that these foods contain and they are stored in the liver, fatty tissue and in the muscles of the body, they are vitamins A, D, E and K.
Water-soluble vitamins are dissolved in body water and are therefore easily eliminated through urine or sweat. They are vitamin C and those of group B. Water-soluble vitamins are not stored in the body, so it is important to consume foods that provide the body with these vitamins, such as egg yolk, cereals, nuts, fish, meat, fruits and fresh vegetables.
Vitamin B12 is an exception among the water-soluble ones since it can be stored in the liver for many years. It has a fundamental role in the formation of red blood cells, cell metabolism, the proper functioning of the nervous system and the brain, as well as in the production of DNA and in the formation of some fundamental proteins for the organism. It is naturally present in many foods of animal origin such as meat, fish, poultry, eggs, milk, and dairy products. Clams and beef liver are some of the best sources of vitamin B12. Sometimes it can be added to some breakfast foods.
Being a vitamin that is obtained from foods of animal origin, people who follow a vegetarian or vegan diet may have a B12 deficiency since vegetables do not contain this vitamin. Some older people, with chewing problems or problems that affect the ability to absorb this vitamin from food, may be susceptible to a vitamin B12 deficiency.
The body absorbs vitamin B12 from food in two phases: first, when food reaches the stomach, hydrochloric acid in gastric juices separates the vitamin B12 from the protein to which it is bound and once released it attaches to intrinsic factor, a protein produced by the stomach, and in the distal small intestine (ilium) the body absorbs the amount it needs into the bloodstream and the rest is excreted in the urine.
Some people do not produce enough Intrinsic Factor or have a problem that destroys it, which can lead to the development of a type of vitamin B12 deficiency called pernicious anemia. Ramon Salinas, Head of the Hematology Service at Hospital Universitari Sagrat Cor, Hospital Universitari General de Catalunya and Hospital Quirónsalud del Vallès explains that “a deficiency of this nutrient can cause tiredness, weakness, constipation, loss of appetite or weight, anemia with increased size and red blood cell deficiency (megaloblastic anemia) as well as neurological problems or poor memory. For children, signs of a vitamin B12 deficiency include delayed growth and development, movement problems, and megaloblastic anemia."
If the food products consumed weekly include meat, fish or shellfish, in addition to a balanced daily diet, the vitamin B12 needs are covered. However, people who follow a vegetarian, vegan or ovolacteovegetarian diet should take a B12 vitamin supplement. The recommended daily amount of vitamin B12 depends on age and stage of life.
It is recommended that children between the ages of 9 and 13 consume 1.8 micrograms per day. Adolescents between 14 and 18 years and adults, 2.4 mcg daily; and pregnant women, 2.6mcg daily. A chicken egg, for example, fried or boiled, has 0.4 micrograms of vitamin B12, therefore, in a lacto-ovo vegetarian diet, 7 eggs should be consumed to cover the basic needs of this nutrient. “In case of following a vegetarian or vegan diet, it is important to find out from a specialist about how to supplement vitamin B12 and carry out analytical controls to avoid this deficit. For example, there are breakfast cereals and other food products fortified with B12 that are an available source of vitamins”, adds the hematologist at Hospital Universitari Sagrat Cor.
But be careful with enriched products because when they are processed they are usually rich in sugars and other ingredients that make it difficult to achieve the recommended dose of vitamin B12, which is why oral supplements are important, which always require the supervision of a specialist.
