“Drink the juice quickly because the vitamins are gone.” How many times have we heard this phrase, especially from the mouth of our mothers, as if vitamins could run out from a glass of freshly squeezed juice. No, vitamins don’t escape anywhere while they’re in a cup, but… what are vitamins, since we’ve been told, since we were little, that they’re so important?
Vitamins are essential micronutrients for cell function, growth and development of the body, and 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 pantothenic acid, B6 or pyridoxine, B7 or biotin, B9 or folic acid, and vitamin B12 or cyanocobalamin. Each of the 13 vitamins performs a specific function in the body and deficiency can cause health problems.
Two classes of vitamins
Vitamins are classified into two categories based on their solubility: water-soluble vitamins and fat-soluble vitamins.
Fat-soluble vitamins are those that can be dissolved in fat. It is obtained through foods such as beef, oily fish, eggs, liver, red and green leafy fruits and vegetables. Easily absorbed by the body thanks to the fats contained in these foods and stored in the liver, adipose tissue, and body muscles, these are vitamins A, D, E, and K.
Water-soluble vitamins dissolve in body water and are therefore easily eliminated through urine or sweat. They are vitamin C and those in group B, and water-soluble vitamins are not stored in the body, so it is important to eat foods that provide the body with these vitamins, such as egg yolks, grains, nuts, fish, meat, fresh fruits and vegetables.
Vitamin B12, an exception
Vitamin B12 is an exception among the water-soluble types as it can be stored in the liver for many years. It has an essential 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 essential proteins for the organism. It is found naturally in many foods of animal origin such as meat, fish, poultry, eggs, milk and dairy products. Clam liver and beef are some of the best sources of vitamin B12. Sometimes it can be added to some breakfast foods.
Being a vitamin obtained from foods of animal origin, people who follow a vegetarian or vegan diet may suffer from a deficiency of vitamin B12 because vegetables do not contain this vitamin. Some elderly people, who have problems chewing or problems that affect the ability to absorb this vitamin from food, may be at risk of vitamin B12 deficiency.
The body absorbs vitamin B12 from food in two stages: First, when the food reaches the stomach, hydrochloric acid in the stomach juices separates the vitamin B12 from its bound protein.
Some people do not produce enough intrinsic factor or have a problem destroying it, which can lead to the development of a type of vitamin B12 deficiency called pernicious anemia. “A deficiency of this nutrient can cause fatigue, weakness, constipation, loss of appetite or weight, anemia with an increase in volume, lack of red blood cells (neuromegaloblasts) or poor red blood cells. For children, signs of vitamin B12 deficiency include delayed growth and development, movement problems, and megaloblastic anaemia,” explains Ramón Salinas, Head of Hematology at Sagrada Cor University Hospital, University Hospital General of Catalonia and Quirónsalud del Valles.
If the food products consumed weekly include meat, fish, or shellfish, in addition to a balanced daily diet, vitamin B12 needs are covered. However, people who follow a vegetarian, vegan, or ovo-vegetarian diet should take a vitamin B12 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 mcg per day. Teens ages 14 to 18 and adults, 2.4 mcg per day; And pregnant women: 2.6 micrograms daily. Chicken eggs, for example, fried or boiled, contain 0.4 μg of vitamin B12, therefore, on a vegetarian diet, 7 eggs should be consumed to cover the basic needs for this nutrient. “In case of a vegetarian or vegan diet, it is important to know from a specialist about how vitamin B12 can be supplemented and to do analytical controls to avoid this deficiency. For example, there are breakfast cereals and other food products fortified with vitamin B12 which are an available source of the vitamin,” adds the hematologist at Sagrat Kaur University Hospital.
But be careful with enriched products because they are usually high in sugars and other ingredients when processed that make it difficult to get the recommended dose of vitamin B12, which is why oral supplementation is so important, which always requires professional supervision.