Vitamin C – What is it, Properties and Benefits

Vitamin C, which is also known as ascorbic acid, is a water-soluble vitamin. It is necessary for growth, since it encourages a healthy immune system and helps to preserve the blood vessels and the connective tissue. Human beings are not capable of producing vitamin C, which is why it must be supplied through the diet.

What is Vitamin C?

Vitamin C is one of the main components of a group of micronutrients, called vitamins, which are spread throughout foods of animal and vegetable origin and that owe its name to their condition of essential elements for the viability of human life.

We should mentio that there is a chemical form of that acid, the R isomer, which lacks vitamin activity, unlike the L isomer.

Looking back, the studies that made it possible to define in the metabolic role of Vitamin C 1927 were the trigger for the award of the Nobel Prize for Medicine to the Hungarian scientist Albert Szent-Györgyi, who specialized in the field of physiology and who cemented the findings about the chemical structure of this compound by Norman Haworth, at the time Nobel for Chemistry in 1937.

Szent-Györgyi used paprika as a natural source of the L isomer from ascorbic acid, which proved the existence of a highly effective innate component to combat scurvy. He completed his research by deepening on the bases of cell oxidation, a feature of the metabolism in which he found that a minor element of the diet played a decisive role, which can be understood as the discovery of Vitamin C.

Vitamin C acts basically as an antioxidant agent in the body which catalyzes chemical reactions that produce a protective effect on the cell membranes to face the constant threat of the free radicals, which can harm the DNA of the cell nucleus. These are groups of atoms that are in a highly reactive state because their molecular structure lacks an electron; This electron looks for another element that will replace the missing one to become stable.

Its formation takes place as a result of the metabolization of the different immediate principles (glucose, lipids, etc.) that contain the food through which they are transformed into energy.

But this is not the only threat that the free radicals can entail. In addition, we are exposed to the action of those which are present in the environment in which we live, like the smoke from tobacco, air pollution or ultraviolet radiation, among other factors.

Functions of Vitamin C

In the specific case of Vitamin C, it is mainly involved in a group of reactions called hydroxylation, which consists of introducing an OH radical in a compound that will substitute a hydrogen atom, which oxidizes the original compound. The coenzymes are responsible for exchanging chemical groups between enzymes without integrating permanently into their structures. That is what distinguishes them from prosthetic groups, which are another type of non-protein structures that are intimately linked to enzymes, among we highlight the iron-sulfur pair or the heme group from hemoglobin.

Science also catalogues vitamins, including Vitamin C, as allogenic biocatalysts, a denomination that comes from two characteristics: a functional one, since its task is to catalyze or conduct biochemical reactions; the other is related to its origin, since it must be supplied to the organism through food sources.

This last statement requires a brief reflection on its nature since about 2.5 million years ago, the first bipedal hominids, our most remote ancestors who followed a diet based on vegetables and animal viscera which has high amounts of this vitamin, lost their ability to synthesize Vitamin C, so that its consumption became inevitable.

Later on, the strict external dependence of this nutrient would have severe effects, with the onset of a disease called scurvy, which is only caused by a lack of Vitamin C due to a poor diet.

Properties of L-Ascorbic Acid

Some interesting data may be its high boiling point (553 °C) and a lethal dose of approximately 12g per kilo of weight, an approximation obtained through experimentation with rats.

Its organoleptic properties, that is, those experienced by the sense organs, are basically being insipid and odorless. On the other hand, it has a remarkable ability to dissolve in water, a chemical parameter that can be quantified as 33g/100 ml, that is, 100 milliliters of water are capable of dissolving up to 33 grams of acid.

Its property of being water-soluble contributes to excreting it through the urine after taking it in therapeutic quantities. In fact, the presence of ascorbic acid in a urine analysis is linked to supplementation, since once the body has enough to meet its needs excretes the rest through the urine. This excretion colors the urine a little with a dark tone and gives it a somewhat stronger odor, without this being indicative of any disorder; however, the fact that it has a higher concentration of ascorbic acid in a minority of cases can cause irritation in the bladder and an excessively frequent urination.

The whole complex, dissolved in an aqueous medium can promote the oxidation of fats. And when it is in the oxidized form, it can cross the blood-brain barrier, a virtual “wall” that separates the blood stream from the encephalic mass, and can be distributed in the brain.

There are multiple applications in the field of medicine and in the field of cosmetics, areas in which it is widely used. Doctors and cosmetologists find Vitamin C an extraordinary tool to intervene in several aspects of health and esthetic.

In the organism, the main functions with which it is related are the formation of collagen, the maintenance of the walls of the blood vessels and capillaries, the metabolism of certain amino acids and the synthesis of the hormones of the adrenal glands. These links and others come from the many benefits associated with Vitamin C that we are going to describe now and most of them have been scientifically proven.

Vitamin C helps with…

Vitamin C: Benefits and Properties

There are many parts of the body that need Vitamin C to successfully complete their functions.

All these functions a great antioxidant power, which becomes a scavenger of free radicals that have the ability to deteriorate the blood vessels, skin and other tissues, accelerating the aging process.

Following the line of some scientific journals such as the “Biochemistry of Human Nutrition”, the ascorbic acid stimulates the production of the different cell lines that make up the immune system, mainly granulocytes, lymphocytes, macrophages and plasmocytes. Regarding the latter, their action results in the production of antibodies that circulate in the blood in quantities that effectively fight the antigens that frequently threaten their presence. They also contribute to the synthesis of interferon, a protein with a somewhat non-specific action but that is the only tool available for the body to destroy viruses.

But the relevant tasks of this nutrient do not stop here: it prevents the iron consumed through vegetables from being wasted and, therefore, it is efficiently absorbed in the intestinal tract. It is also a limiting factor in the synthesis of collagen and the formation of red blood cells from stem cells of the red bone marrow.

A deficiency of Vitamin C can be indirectly linked to the onset of several disorders since it is involved in a great number of biochemical reactions. There is enough medical consensus about the fact that higher doses of what is usually advised, also known as therapeutic doses, can enhance the treatment for a great number of disorders, like inflammatory processes such as arthritis, hepatitis and pancreatitis; infections such as pneumonia, herpes, mononucleosis, bladder infections, cold or flu; degenerative processes such as arteriosclerosis, multiple sclerosis, glaucoma and corneal ulcer, as well as cancer, asthenia or chronic fatigue, the effects of alcoholism, diabetes, surgical complications, cardiac alterations and skin striae.

It is also one of the main palliative arguments to buffer the effects of stress along with the B complex vitamins.

Linus Carl Pauling, a biochemist awarded the Nobel Prize in Chemistry in 1954, was one of the main supporters of the treatment with high doses of Vitamin C to fight against colds and other respiratory processes.

In a study led by Dr. James Engstrom, he found that individuals who take 800 milligrams of Vitamin C daily – almost eleven times the Recommended Daily Amount (RDA) – have lowered the risk of suffering a cardiovascular disease and significantly increased their life expectancy (six years) than those that are treated with the conventional dose of 60-80 mg.

Now, we are going to break down the main details of the contribution of Vitamin C in various pathologies.

Vitamin C in the prevention and treatment of Cancer

Those people who take high quantities of vitamin C through food reduce the risk of suffering several types of cancer, particularly lung, breast and colon cancer.

But the interaction of this substance with the mechanisms of genesis and control of cancer is kind of controversial. First of all, its effects seem to be related to the way it is administered, since there is evidence that vitamin C supplementation has a low efficiency in cancer prevention, either if it is isolated or combined with other antioxidants.

In fact, some tests carried out with animals suggest that maintaining very high levels of Vitamin C in the blood could reduce malignant tumors, but the doses that are taken orally are never enough to produce these levels in the blood, which can be reached using the intravenous administration. However, it is necessary to perform an important amount of research to turn a plausible speculation into reality.

A few years ago, the renowned oncologist Bert Vogelstein from the Johns Hopkins University proved how the molecule of L-ascorbic acid with its antioxidant properties, blocks a protein called HIF-1, that has been identified as the elements that allows tumor cells to obtain energy from glucose when there is no oxygen.

On another note, we should keep in mind that vitamin C dietary supplements can react to the therapeutic mechanisms of chemotherapy and radiotherapy. So, it is highly advisable for patients undergoing cancer treatment to consult the oncologist about the plausibility of carrying out the supplementation.

Vitamin C and its implication in cardiovascular diseases

It is quite possible that foods rich in Vitamin C lower the risk of cardiovascular disease, which could be partly explained by the fact that one of the main triggers of cardiovascular disorders is oxidative damage to the cells.

Macular degeneration and cataracts

Macular degeneration and the opacity of the natural lens are perhaps the main causes of sight loss in the elderly.

In relation to this, the researchers indicate that there is a possibility that Vitamin C, in synergy with other nutrients, would be effective in slowing both the increase of macular degeneration linked to old age and the damage to the lens.

A Classic: Colds and Vitamin C

In this chapter, it is worth reviewing the excessive prominence that it has been traditionally assigned to Vitamin C, since most of the conclusions obtained in the research studies refute the belief that using Vitamin C supplements prevents the risk of catching a cold.

The medical basis for these effects is that Vitamin C enhances the ability to synthesize interferon and antibodies, which are ultimately the weapons with which the body fights the viruses of the common cold.

Vitamina C is fundamental synthesizes collagen

Collagen is the main structural protein of the body, which mainly makes up the matrix of subcutaneous connective tissue, bones, tendons, ligaments, gums and mucous membranes of multiple organic elements, such as the wall of blood vessels, the muscles and different viscera.

From the age of 30 onward, the amount of collagen in the body drops considerably, compared with the one we have at birth, accelerating its loss in arithmetic progression.

This makes it essential to have a proper physiological mechanism of endogenous collagen production, since its supply through food as such is practically impossible. However the consumption of the hydroxyproline and hydroxylysine amino acids is quite feasible, and they are involved in the synthesis of collagen as well as Vitamin C; without adequate levels of these, the reactions that lead to this synthesis are not viable, hence the relevance of this vital substance.

But in general, it is necessary to repair all kinds of damaged tissues. In particular, a recent study from the University of Leicester proved its effectiveness in accelerating the healing of skin wounds; This function is based on stimulating specialized connective tissue cells, the fibroblasts, so that they gather around the injured area.

An important stress mediator

Surprisingly, the adrenal glands are the organs that have more vitamin C. But its role in that location is key for the synthesis of the adrenaline and noradrenaline hormones and glucocorticoids. This explains more than enough that during stressful periods the needs of this vitamin are high because they are hormones that are strongly linked to the biochemical cascade of the general adaptation syndrome, commonly known as stress.

On the other hand, adrenaline and norepinephrine are essential neurotransmitters for the functioning of the brain and keep an intense link with the mood and the attention spawn.

Vitamin C against oxidative stress

In situations of high organic demand, such as the intensive practice of sport, it produces a metabolic imbalance that favors the production of free radicals, in which Vitamin C plays a crucial role by inhibiting the cascade of reactions that these cause. In situations of constant aggression by these free radicals (contaminated environments, an excess of ultraviolet radiation …), the needs of Vitamin C increase, since it is the best tool to stop them.

It is interesting to mention that, in particular, it prevents the DNA of skin cells from becoming denatured when they are exposed to excessive ultraviolet radiation.

A bulwark within the immune system

L-ascorbic acid provides a solid support for the immune system, strengthening the population of the several lines of white blood cells (especially neutrophils, lymphocytes and macrophages), as well as optimizing the synthesis of immunoglobulins or antibodies.

In case of a Vitamin C deficiency, the lymphocytes are used to fix it at the expense of that demanded by the tissues.

Other implications of Vitamin C for health:

Main sources of Vitamin C

There is a highly extended myth that states that oranges are the fruit that contains the highest concentration of this micronutrient. But this is not true, since one piece of this citrus provides 69 milligrams of Vitamin C, a bowl of strawberries provides 85, a slice of mango 122 and if we are talking about a piece of red pepper, about 200.

On the other hand, although to a lesser extent, it is interesting to know that some processed cereals and other processed foods that are enriched or enhanced with Vitamin C.

However, it should be taken into account that, as it has been already mentioned with regard to the properties of ascorbic acid, it is an extremely labile substance. This means that it should not be too cooked or manipulated or stored for a long period of time. Humid cooking is lethal to the viability of Vitamin C, so microwave or steam cooking can reduce its deterioration, although there is always some loss.

Recommended Amounts of Vitamin C

For this purpose, we have created a table with information that always refes to healthy people, depending on their age:

Babies

• 0 to 6 months: 40 mg/day
• 7 to 12 months: 50 mg/day

Children

• 1 to 3 years: 15 mg/day
• 4 to 8 years: 25 mg/day
• 9 to 13 years: 45 mg/day

Adolescents

• Girls 14 to 18 years: 65 mg/day
• Boys 14 to 18 years: 75 mg/day
• Pregnant adolescents: 80 mg/day
• Lactating adolescents: 115 mg/day

Adults

• Men: 90 mg/day
• Women: 75 mg/day
• Pregnant women: 85 mg/day
• Lactating women: 120 mg/day

But there are some people who have more problems to get enough Vitamin C, for example:

We have to give a special mention to the opinion of the followers of the so-called orthomolecular medicine, led by the Nobel Linus Pauling. They advise a consumption ranging from 3 to 18g daily, divided into five or six servings, since its absorption by the organism is limited. They base this method on the consumption pattern of primate species in general and, on the other hand, in the volume of Vitamin C that is synthesized by non-primate mammal species when they are subjected to stress.

It should be noted, however, that these theory has had a limited approval within the scientific community.

On the other hand, we must bear in mind that Vitamin C has some enemies that can cause its degradation in the body; we talk about certain medications such as the contraceptive pill, some antibiotics and acetylsalicylic acid, the basic compound of aspirin. At the same time, it can be reduced by surgeries, wounds and severe burns, infections, diabetes, digestive diseases and the disproportionate consumption of alcohol or tobacco.

Myths and truths

1. Citrus have to be consumed just after being squeezed to absorb the vitamin C:

True. The citrus fruits must be consumed just after being squeezed to absorb the vitamin C. When they come into contact with oxygen, the vitamin C present in citrus fruits loses its properties. It is also important to keep juices at a moderate temperature and away from light if possible.
Similarly, foods such as peppers, chard, broccoli or strawberries should be consumed raw to absorb the vitamin C properly. This is because the cooking reduces the supply of nutrients.

2. Eating citrus fruit on an empty stomach helps to burn fat:

False. Citrus fruits alone are not enough to burn fat. There is no scientific evidence that directly grants them this property.
It is true that they reduce the cholesterol levels and act as antioxidants, neutralizing the oxidative effect.

3. Taking vitamin C can prevent and cure colds:

This myth, at least to a great extent, is false. Vitamin C does not have the capacity to prevent or cure a cold. It has the potential to reduce the symptoms once the illness has started and to shorten the duration of the cold. The chances of succeeding depend on each person’s body and the conditions of the cold.
The best way to prevent a disease or accelerate the healing process is to eat properly, including, of course, vitamin C sources.

4. Vitamin C is good for the bones:

True. Although we know that bone health is directly associated with calcium, vitamin C enhances its utility and it is also fundamental for the formation of collagen. This production of collagen contributes to the maintenance of a healthy and firm skin and it is indispensable for the connective tissues, joints and tendons.
In addition, the antioxidant properties of vitamin C reduce bone loss, slows down the aging process and helps to preserve the bone density over time.

5. Citrus fruits are the only source of vitamin C:

That’s a lie. While citrus is one of the most important sources of this vitamin, there are foods that contain much more vitamin C than an orange. Some of them are: peppers, chard, broccoli, strawberries and cauliflower.

Conclusions

That is why it is advisable to follow a balanced diet and instead of focusing on some particular foods, we should eat more quantity and variety.

Do you need supplementation?

According to the Dietary Guidelines for American people, it would be ideal to obtain all the indispensable nutrients from their natural food sources. But consuming enriched foods and dietary supplements is a way to make sure that we reach the minimum thresholds of certain nutrients in order to avoid compromising our health.

Certainly, there are many people who do not follow a proper diet and, therefore, do not consume enough fruits and vegetables. In these cases, it is crucial to take Vitamin C supplements, which can be included in a larger supplementation plan to favor a good state of health.

Vitamin C is found in most multivitamin supplements that are sold in herbalist’s shops, pharmacies and parapharmacies, including online stores, and it can also be purchased both alone or combined with nutrients.

In general, these supplements contain the form of L-ascorbic acid, but some manufacturers tend to choose salt formats in the form of sodium ascorbate, calcium ascorbate or other ascorbates, and it is also possible to find a combination of Ascorbic acid with bioflavonoids. In fact, there is no evidence that any of these chemical forms is better than the other.

Perhaps Vitamin C is the best known nutrient because its supplementation is the most widespread. It is available in several formats, such as tablets, capsules, tablets, solid drink blends and crystalline powder. The latter are basically bottles with Vitamin C crystallites, a teaspoon of which contains half a gram of vitamin. L-ascorbic acid powder has a strong bitter taste and can cause gastric irritation in high doses if we have a delicate stomach.

In a hugely crowded market of dietary supplements, it is possible to find variegated forms of Vitamin C, associated with different claims in relation to their bioavailability, which refers to the degree to which a nutrient acquires a sufficient degree of availability in the tissue to which he is destined to exercise its effect after being taken.

Check the best vitamin C supplements available here.

The option of Ascorbic Acid salts

Sodium, calcium and magnesium ascorbates are ascorbic acid salts which are chemically bound to sodium, calcium or magnesium, representing non-acid forms of vitamin C that are easier to tolerate and more efficiently absorbed in the gastrointestinal tract.

The possibility that the bioavailability of L-ascorbic acid from natural sources may differ from the synthetic has been the subject of several studies, without any clinically significant difference between them being observed. On the other hand, forms of ascorbic acid that are eaten with food or the so-called prolonged release formats should increase the absorption because the digestion is slower. There is some uncertainty surrounding these prolonged-release formats, while there seems to be no doubt about the equivalence of the bioavailability of ascorbic acid in the form of chewable powders or tablets.

When we consume salts from ascorbic acid, both the ascorbic acid and the mineral are quickly absorbed almost in their entirety, so the quantity of those minerals that are part of the complex must be taken into consideration when adjusting the doses of ascorbate. Therefore, it is convenient to check the labels of the supplements to have precise knowledge of the dose of ascorbic acid and each mineral.

Sodium Ascorbate

One gram of sodium ascorbate contains 111 milligrams of sodium.

People who suffer hypertension usually follow a low sodium diet and should keep their sodium intake under 2.5 mg/day. Therefore, these people would not be able to benefit from this format.

Calcium ascorbate

In this way, calcium seems to be absorbed quite well. The recommended intake for adults is from 1 to 1.2 mg/day, not exceeding 2.5 mg/day for those between 19 and 50 years and 2 mg/day for those who are 50 or older.

Magnesium Ascorbate

The recommended daily dose of magnesium for adults is 400-420 mg/day for men and 310-320 mg/day for women. While the threshold for magnesium supplements lies at 350 mg/day.

Manganese Ascorbate

We specifically mention it because it is an ingredient of some formulations that contain glucosamine or chondroitin sulphate as the main ingredient, and adapting the dose according to the label of the product, the tolerable level of manganese, which is 11 mg/day, could be exceeded.

Vitamin C with Bioflavonoids

The bioflavonoids are phenolic compounds present in the vegetable kingdom, coinciding in many occasions its abundance with that of Vitamin C. But according to the results of several clinical studies that compared how Vitamin C was absorbed alone and on the other hand contained in flavonoids. There seems to be a difference in the bioavailability of ascorbic acid. In conclusion, the effect of bioflavonoids on the biological availability of Vitamin C seems to be irrelevant.

Ascorbyl Palmitate

It is an antioxidant that is mainly used is to prolong the durability of vegetable oils. But its biomedical utility should not be overlooked, since it has the ability to enter the cell membranes due to its dual solubility, that is, in water and fats. In particular, although this effect is still waiting to be confirmed, when it is fixed in the membrane of red blood cells they are protected against the oxidative damage from the free radicals, knowing that it also does the same with vitamin E.

When taken orally, it is suspected that it is broken down in its two constituents, palmitate and ascorbic acid (this also bioavailable that ingested in isolation), in the digestive tract before its absorption and it never becomes part of the cell membranes. However, it is assumed that the presence of palmitate in supplements will always be a protective factor for the water-soluble antioxidants contained in the formulation.

As can it be deduced from all these facts, the main problem to assess the suitability of vitamin C supplementation is the enormous disparity between doses and administration patterns.

Some mandatory precautions for Vitamin C supplements

It is worth pointing out a couple of situations related to taking medicines in which we present some of the possible effects of Vitamin C dietary supplements of and unwanted interactions:

Four reasons why we should include vitamin C in the diet

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