The fundamental role of vitamins in health is well known but there are many doubts about how to obtain them properly and in fair doses.

What are vitamins? Vitamins are substances that the body needs in negligible amounts per o that are essential for the metabolic processes on which life depends.

The way to ensure that they are obtained in the necessary quantities is to follow a varied diet with lots of fresh fruit and vegetables, but nevertheless we have become accustomed to imagining them as remedies for sale in pharmacy or in health food stores.

It is true that serious vitamin deficiencies have virtually disappeared in our society but, contrary to what our current food abundance may suggest, mild deficiencies are not rare.

At the opposite pole, vitamin excesses occur in the vast majority of cases due to an unbalanced consumption of supplements.

These are data that reveal that popular knowledge about vitamins is inaccurate and that many doubts persist about them. In this article we intend to solve the most common ones.

HOW TO GET THE NECESSARY VITAMINS THROUGH FOOD?

Many different diets can provide the desirable dose of vitamins, but in general a balanced diet that includes vegetables, fruits, protein foods, quality cereals, dairy and fats is enough for a healthy person.

Hence, in developed countries there are few problems due to vitamin deficits.

Another thing is to ingest the ideal level of vitamins to prevent certain diseases, exert antioxidant power or optimize the performance of the immune system. The vitamin dose needed to obtain these possible effects is being investigated.

WHAT MAKES A FOOD LOSE VITAMINS?

Vitamin C, for example, soluble in water and present in vegetables, is very labile to light, temperature and oxygen. So, when storing a vegetable or fruit, vitamins are already lost.

In general, to preserve the maximum vitamins, especially water-soluble vitamins (group B and C) you have to take fresh food, subject them to minimum cooking, store them as little time as possible and avoid peeling and chopping them too much.

HOW ARE VITAMINS BEST USED IN FOOD?

The ideal thing is to eat fresh food, keep it as little time as possible and in optimal conditions, and not cook it or do it briefly, but it is also important to know how to combine them.

A diet too rich in fiber can make it difficult to absorb some vitamins and minerals. On the other hand, the presence of vitamin E makes vitamin A better preserved.

Keep in mind that different nutrients influence and interact with each other.

As it is a complex issue, it is best to vary the type of food in the diet and always keep in mind that none provides all the vitamins.

Without forgetting that for the correct absorption of all vitamins you have to have a healthy digestive system.

CAN VITAMIN DEFICIENCIES BE SUFFERED WITH A BALANCED DIET?

Yes. Some circumstances can increase vitamin requirements. An example is people who smoke, drink high doses of alcohol, are subjected to a lot of stress, take medications continuously or practice sports with a certain intensity and regularity.

In addition, as already explained, the choice of food, its conservation, cooking and, ultimately, handling are factors that influence the final vitamin content that the body absorbs and that should be taken into account.

ARE SOME VITAMINS MORE IMPORTANT THAN OTHERS?

All vitamins are substances that the body needs, essential for life.

However, some such as vitamin D or vitamin K are obtained, apart from food, by internal synthesis.

For example, solar radiation causes an endogenous production of vitamin D, essential for calcium absorption. Therefore, in countries with more sun, a lower dose of vitamin D is needed.

For its part, vitamin K, which is directly involved in blood clotting, is obtained in part by a process of endogenous synthesis in the intestinal flora (although it is necessary to obtain a complement of green leafy vegetables).

Vitamin K deficiency is suffered by people with chronic and severe intestinal diseases.

WHY ARE CERTAIN VITAMINS ANTIOXIDANTS?

Antioxidant is the name given to a substance that prevents oxidation and, in this case, refers to vitamins that prevent or reduce the consequences of oxidation in the body.

The body needs to use oxygen in thousands of reactions, such as cellular respiration, which produces “waste substances,” some of them called free radicals. These substances can cause harmful effects in the body.

In fact, it is known that some diseases (arteriosclerosis, some types of cancer …) have their origin in oxidation.

The body has its own resources to neutralize and deactivate these toxic free radicals and uses, for example, some of the vitamins it obtains from the diet, specifically provitamin A, C and E, as well as minerals such as zinc or selenium.

The problem is that with age or simply in the face of increased oxidation, antioxidant resources may be insufficient. It is rightly said that aging is a process of oxidation … Hence the importance of adequate antioxidant vitamins.

WHAT FOODS HAVE ANTIOXIDANT VITAMINS?

An antioxidant diet includes foods rich in all three antioxidant vitamins (A, C, and E).

• Vitamin C is present in fruits and vegetables, especially orange, kiwi, strawberry, mango, raw red pepper or cabbage;
• vitamin E, in vegetable oils, cereals and nuts;
• and provitamin A, in yellow or orange fruits such as apricot, peach, yellow melon, etc. and especially in carrots, sweet potatoes and pumpkin …

Keep in mind that for antioxidant vitamins to exert this effect they have to be present in the diet not only in sufficient doses to avoid deficiencies but in much higher quantities.

DOES A HYPOCALORIC DIET PROVIDE ENOUGH VITAMINS?

It is possible but not always easy. It depends on how the hypocaloric diet is. If it provides less than 1,200 Kcal it is difficult to provide the necessary vitamins. This is one of the reasons why it is advised that diets always provide more than 1,200 Kcal.

On the other hand, the diet has to be balanced and varied. If it is very repetitive or only allows eating certain food groups can lead to significant vitamin deficits.

An example is that of diets that suppress fats: it is quite common that they present significant deficits because provitamin A, vitamin D and vitamin E are transported by fats. The same can be said of diets that advocate “fruit day”, or any other food.

DOES A PREGNANT WOMAN NEED VITAMIN SUPPLEMENTS?

On this point there is a disparity of criteria.

Before a pregnancy, the body takes its “measures” so that the vitamin intake is adequate for the mother and the baby. One of these measures is that it increases the mother’s appetite and vitamin absorption from the diet, since vitamins are absorbed in different proportions according to needs.

The problem is that it is not always clear what it means to “eat well”, and also that there are pregnant women who have already been pregnant recently, or that they may be people who have followed diets, have been heavy smokers, have been taking drugs …

In summary, although the need to prescribe supplements during pregnancy is not proven, there are many circumstances that make it very advisable.

What is proven is that taking folic acid in the periconceptional era can be a way to prevent future problems in the baby’s neural tube. Even so, phallic acid is not always prescribed to women who want to get pregnant.

ARE VITAMIN SUPPLEMENTS FATTENING?

Vitamins are essential substances for the proper functioning of the body but do not provide energy.

It is often believed that vitamins can make you fat or increase appetite and it is not true.

What is true is that certain vitamins or vitamin complexes can elevate mood, including those of the B complex, and this can indirectly cause a physiological increase in appetite. In any case, it would be a normal sensation, not increased.

What happens is that in some deficiency states or in people who eat unbalanced, appetite is decreased. Having an appetite is physiological and normal. It is the extremes, due to excess or deficit, that can be pathological.

CAN AN ANTI-CHOLESTEROL DIET BE DEFICIENT IN VITAMINS?

Not necessarily, if it is well designed. It is true that it reduces animal fats (fatty meats, dairy products, etc.), so its contribution of vitamins A and D can be reduced, but fortunately it can be compensated with vegetables that provide provitamin A (carrot, sweet potato, tomato …), dairy products enriched with vitamins A and D and regular exposure to the sun.

In general, combining food well can always compensate for possible shortcomings. Hence, good advice is essential.

DO VEGETARIANS SUFFER FROM VITAMIN DEFICITS?

If the vegetarian diet includes eggs and milk, it provides everything you need. If it is strict, it may present some deficiency, especially vitamin B12. But, well designed, it does not usually lead to problems.

It is important to be well advised on the choice and combination of foods, and resort to a supplement if necessary.

Many healthy people follow strict vegetarian diets, although there is no doubt that it is much easier to get all the nutrients with other diets.

DOES AN OLDER PERSON NEED MORE VITAMINS?

There are no major differences between the vitamin needs of each stage of life, but older people may absorb vitamins worse than younger people. This means that your diet should be taken care of much more since the use of vitamins and other nutrients may be lower.

To this we must add that older people can suffer from chronic diseases that modify vitamin requirements, or they can follow a medication that interferes with the absorption of nutrients.

People over 65 should generally follow a more vitamin diet than young people, contrary to what is usually the case.

ARE VITAMIN-ENRICHED FOODS ADVISABLE?

They can be a help for people who have to follow special diets. Now, this does not mean that a person can make up for their lack of vegetables and fruits in the diet by drinking an enriched refreshing drink or something similar.

Do not forget that the vitamins that are best absorbed are those of food, much better than vitamins in supplements. Hence, the best medicine is a balanced diet.

On the other hand, many of the fortified foods provide minimal doses of vitamins. It would be necessary to ingest them in a very high amount.

ARE VITAMIN SUPPLEMENTS ADVISABLE?

In general, if you follow a balanced diet, vitamin supplements are not needed. In addition, there are studies that indicate that the effectiveness of vitamins in food is superior to that of these supplements.

Yes, they may be advisable in some pregnant women, convalescent people, people with intestinal diseases, who follow very strict or unbalanced diets, elite athletes, children, the elderly, people with a lot of stress, swallowing or alcohol problems.

There are doses of vitamins considered optimal and maximum recommended doses that vary depending on the source. It is always advisable to know how much vitamins you are taking and not abuse them: excesses can lead to as many problems as deficits.

ARE LARGE DOSES OF VITAMINS DANGEROUS?

An excess of vitamins can be harmful, especially if it is fat-soluble vitamins (A, D, E and K), which can accumulate.

Overdose of vitamin A can cause vomiting, dizziness, headache and muscle disruption. In addition, an excess of vitamin A for a long time can also have teratogenic effects, that is, produce malformations in the embryo or fetus.

CAN TAKING TOO MUCH VITAMIN C CAUSE PROBLEMS?

That’s right. Even this vitamin, which is water-soluble and therefore easily eliminated in the urine, can cause problems if taken excessively.

There are studies that show that an excess of vitamin C can cause abdominal swelling, a tendency to renal lithiasis, an increase in uric acid and a decrease in vitamin B12, among other consequences.

It is interesting to note because, due to its great popularity, vitamin C is taken freely in large doses, when in fact a more or less conventional diet already provides considerable amounts of this vitamin.

CAN YOU TAKE MORE VITAMINS THAN RECOMMENDED WHEN TAKING A SUPPLEMENT?

Quality supplements should always indicate how much vitamins they provide and especially at what dose or proportion of the recommended daily requirements each tablet is equivalent. It is not usual for vitamin supplements to provide more than recommended as a minimum dose. What is possible is that they are taken in a high dose.

WHAT ARE THE SYMPTOMS OF A VITAMIN DEFICIENCY?

In our environment, diseases caused by vitamin deficiencies are very rare, but there are nonspecific symptoms, such as fatigue, headache or apathy, which may have their origin in insufficient doses.

It is not always easy to know if sufficient doses of vitamins are taken (routine medical examinations do not usually consider this data), but when they are clearly lower than desirable, the following symptoms appear:

• Vitamin A: decreased visual acuity, loss of night vision, growth retardation, skin disorders, dry skin, increased sensitivity to infections.
• Vitamin B1: growth abnormalities, muscle weakness, neuralgia, beriberi.
• Vitamin B2: alterations of vision, alterations of the skin, alteration of the mucous membranes, fatigue, malaise.
• Vitamin B3: mental disorders, diarrhea, dermatitis (pe-! agra), lack of appetite, fatigue, depression.
• Vitamin B5: cramps, hypersensitivity, neurological alterations.
• Vitamin B6: dermatitis, acne, arthritis, weakness, depression.
• Folic acid: mega megaloblastic anemia, neural tube alterations in newborns (when the deficiency is in pregnant women),
• Vitamin B12: anemia, nervous disorders.
• Vitamin C: bleeding gums, difficulty healing, cartilage alterations, musculoskeletal pain.
• Vitamin D: osteomalacia, rickets, musculoskeletal disorders, osteoporosis.
• Vitamin E: muscle disorders, alterations in fertility, dermatitis in children, rupture of red blood cells.
• Vitamin K: bleeding, coagulation disorders.

DEFICIENCY DISEASES

Problems due to insufficient vitamin intake are, fortunately, a rarity in our environment. There are usually no cases of scurvy (lack of vitamin C), or beriberi (lack of B1) or rickets (lack of vitamin D). This does not mean that vitamin doses are always recommended.