The Fundamental Importance of Vitamin C for Health: An In-Depth Look

Vitamin C, also known as L-ascorbic acid, is widely recognized, especially since the 16th century when scurvy began to be prevented with citrus fruit juice. But then, what exactly is ascorbic acid for?

Image 1: Structural formula of ascorbic acid with ketone

Main features

First, let's start by evaluating its main features. The term L in its name is related to its optical activity, since it has a chiral carbon in its structure. This substance is characterized by:

• At room temperature, it is a crystalline solid;
• It comes in white or yellow;
• It is quite soluble in water;
• It is soluble in ethanol;
• It has no solubility in organic solvents of the Hydrocarbons , ethers It is ketones ;
• It is a denser compound than water;
• Its flavor is sour;
• In the solid state, it is a very stable substance;
• In aqueous or alcoholic solutions, it always undergoes oxidation, that is, it is not stable.

Okay, all very interesting, but that's probably not what you wanted to know, right?
So let's move on to what really matters when it comes to human beings.

Main functions and benefits of Vitamin C

The main features and benefits of Vitamin C for the human body are:

• Participation in tissue growth (bones, tendons, muscles, skin, among others);
• Participation in the regulation of the central nervous system ;
• Defense of the body against infections ;
• Helps maintain the integrity of blood vessels ;
• Participation in the wound healing process ;
• Influence on increasing iron absorption in the intestine;
• Participation in the production of neurotransmitters (such as dopamine and noradrenaline), etc.

Vitamin C is essential for the functioning of the immune system and acts as a cofactor in collagen synthesis, being crucial for the health of the skin, blood vessels, tendons and bones. Its antioxidant properties protect the body against oxidative stress, helping to prevent various chronic conditions.

We already realize that vitamin C has immense benefits for our body, but does it really help in the treatment and prevention of diseases?

Efficacy in the Treatment of Colds

Although many turn to vitamin C in hopes of avoiding colds, scientific evidence shows that it is more effective in reducing the duration of symptoms than in preventing them from occurring. Recommended doses for these effects vary between 200 mg and 2000 mg .

Antioxidant Potential

Vitamin C has been studied in the context of diseases such as Alzheimer's disease and cancer, and it has been observed that patients with Alzheimer's have reduced levels of this nutrient, even with adequate intake, which suggests the role of oxidative stress in the development of the disease. .  As an antioxidant, the main role of vitamin C is to neutralize free radicals by donating electrons to them, reflecting its reducing capacity and ability to reduce oxidative stress . However, some controversial studies suggest that this nutrient may have a preventive and therapeutic role in cancer due to its possible pro-oxidant activity, promoting the formation of reactive oxygen species that can induce cell death in cancer cells. Some results from studies in rodents indicated that vitamin C may promote oxidative stress in cancer cells, resulting in cytotoxic effects.

In addition to its therapeutic potential, the presence of this vitamin in our diets prevents a series of problematic conditions.

Problems due to lack of Vitamin C

A lack of vitamin C in the body can cause a series of effects, depending on the duration of the vitamin deficiency and the severity of the situation:

• Increased susceptibility to infections ;
• Decrease in the speed of the healing process ;
• Anemia , due to decreased iron absorption;
• Fatigue, paleness and dizziness , due to anemia;
• Purple spots on the body , also due to the fragility of blood vessels;
• Bone deformities and increased risk of invoices , especially in children;
• Hair loss , weakening of nails, cartilage and joints;
• Softening and possible loss of teeth , as it alters the formation of dentin, the matrix of the teeth;
• Sadness and difficulties in reasoning , since a lack of this vitamin can produce chemical changes in the brain;

Recommended Dosage

The daily intake of vitamin C recommended by the World Health Organization is 45 mg for most adults. However, in the US and EU, the suggested minimum daily doses are slightly higher. More recent studies demonstrated that this amount was too low.

The minimum was set at 75 mg for women and 90 mg for men in the USA, and at 95 mg for women and 110 mg for men in the European Union. For specific objectives, such as supporting the immune system or relieving the duration of colds, doses of up to 2000 mg are recommended. Additionally, a 2022 study that used 110 mg as a starting number recommended adding 10 mg for every 10 kg (22 lb) over 60 kg (132 lb) of body weight.

But pay attention ! If you take too much vitamin C, it can cause some side effects.

Secundary effects

Vitamin C supplementation is safe within recommended doses, although high doses can cause side effects such as:

• Diarrhea;
• Nausea;
• Vomiting;
• Abdominal pain;
• Allergic reactions;
• Excessive absorption of iron;
• Rarely, nephrotoxicity.

Furthermore, research from the Karolinska Institute in Sweden showed a greater possibility of kidney stones in people who consumed high doses of the vitamin. The study published in 2013 looked at men between 45 and 79 years old for 11 years. Volunteers who ingested twice the recommended total vitamin C had a higher risk of kidney stones compared to those who did not use this type of nutrient, but more data would be needed to establish a correlation.

It is recommended to seek medical advice before consuming Vitamin C supplements.

Foods Rich in Vitamin C

To ensure an adequate intake of vitamin C, it is recommended to include a variety of foods rich in this nutrient in your daily diet. Among them the following stand out:

• Citrus: oranges, grapefruits, lemons and limes.
• Berries: strawberries, raspberries, blueberries and currants.
• Kiwi: known for its high concentration of vitamin C.
• Peppers: red and green, both are excellent sources.
• Broccoli and Cabbage: including Brussels sprouts and cauliflower.
• Tomatoes: fresh and in juice.
• Green Leaves: spinach, turnip greens and kale.

Incorporating these foods into your diet not only contributes to the recommended daily intake of vitamin C, but also offers a diverse range of other essential nutrients, promoting a balanced and healthy diet.

Conclusion

Vitamin C is an essential pillar in promoting health and preventing disease. Including foods rich in vitamin C in the diet, along with conscious supplementation when necessary, can be an effective strategy to improve overall health. It is always recommended to consult a healthcare professional before starting any supplementation regimen.

References

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