Vitamin C—How Is It Beneficial for the Skin? Daily Recommendations, Content in Foods

Vitamin C (ascorbic acid) is one of the essential nutrients in the human diet, necessary for the normal functioning of connective and bone tissue. It is not produced by the body and must be obtained from food. Rose hips, red bell peppers, sea buckthorn, and black currants, as well as various citrus fruits, are the richest sources of vitamin C.

Meeting the daily requirement for vitamin C is essential, first and foremost, for maintaining healthy skin. A deficiency of this vitamin is associated with impaired collagen synthesis, leading to damage to the gums and other body tissues. In addition, ascorbic acid affects the absorption of iron and a number of vitamins (primarily B vitamins and fat-soluble vitamins).

Consuming the recommended daily intake of vitamin C improves the ability of cell membranes to resist various damaging factors—ranging from pathogenic viruses and sunlight, to combating inflammation in muscle tissue after exercise. In medical practice, ascorbic acid is used to treat intoxication and to accelerate the healing of minor wounds.

Vitamin C for the Skin

One of vitamin C’s most important functions is its role in collagen synthesis—collagen is the primary structural protein of connective tissue, ensuring the functionality and strength of the skin, bones, tendons, and blood vessels. This substance is widely used in the cosmetics industry—when applied directly to the skin, vitamin C helps brighten it and combat dark spots.

What Is Vitamin C Used For?

• to maintain the health of the skin and other body tissues
• fights free radicals
• is involved in the synthesis of a number of hormones
• improves the absorption of vitamins and minerals

Vitamin C Deficiency: Symptoms

The main cause of ascorbic acid deficiency in the body is usually a lack of fresh fruits and vegetables in the diet—the vitamin is destroyed during heat treatment. Unhealthy habits also play a role—alcohol and nicotine significantly accelerate the elimination of ascorbic acid from the body. The daily requirement for vitamin C for smokers increases by one-third—approximately 20–30 mg¹.

Typical symptoms of a deficiency in this vitamin include slow wound healing, increased nail brittleness, brittle hair and hair loss, a weakened immune system (and thus a higher risk of catching a cold), and chronic fatigue. Since the body needs this vitamin to absorb iron, the symptoms of a deficiency in both often overlap.

Daily Recommended Intake of Vitamin C

• for men — 90 mg
• for women — 75 mg
• For adolescents — 65–75 mg
• For children under 13 years of age — 35–50 mg

Ascorbic Acid for the Common Cold

Although a lack of vitamin C in the diet weakens the body’s defenses and increases the risk of catching a cold, taking ascorbic acid alone cannot cure viral illnesses or speed up the course of an infection. The laws of many countries prohibit the use of the term “cures” on the packaging and in advertisements for vitamin C supplements intended to treat acute respiratory viral infections (ARVI).

Scientific studies show that even high doses of ascorbic acid are not effective in curing the common cold. Only in some cases was a slight reduction in the duration of the illness observed—about 8% in adults and 14% in children². However, this was observed only with regular use.

Vitamin C Overdose

A one-time dose of up to about 3,000 mg (3 g) of ascorbic acid can be taken without harm to health—which is equivalent to one kilogram of rose hips or 6 kg of oranges or lemons. In other words, it is possible to overdose on ascorbic acid only by taking supplements, not by consuming regular foods—no matter how rich in vitamin C they may be.

It should also be noted that vitamin C is water-soluble (unlike the fat-soluble vitamins D, E, K, and A)—it does not accumulate in the body’s tissues and is not toxic. The harmful effects of an overdose mainly manifest as symptoms of food poisoning—for example, stomach problems, diarrhea, nausea, and excessive sweating.

Symptoms of a Vitamin C Overdose

• Sharp pains in the stomach
• Izgozha
• Vomiting
• Diarrhea
• Insomnia

Vitamin C Overdose in Children

In children, the symptoms of vitamin C overdose resemble those of a food allergy. They include itching, redness on the body, and digestive problems.

Foods Containing Vitamin C

Although oranges, lemons, and other citrus fruits do contain ascorbic acid, they do not contain it in as significant amounts as is commonly believed. The foods richest in vitamin C are fresh rose hips, sweet red peppers, sea buckthorn berries, black currants, green parsley, and spinach leaves.

It should be noted that the vitamin C content figures for foods are always approximate—the actual content depends both on how a particular plant is grown and on how the food is consumed. Another factor is that ascorbic acid breaks down during storage and when subjected to heat treatment (especially during cooking).

Vitamin C Content in Foods

Vitamin C is one of the most important substances for health; it is not produced by the body and must be obtained from food. Ascorbic acid is essential for immune function, tissue regeneration, and nutrient absorption. Although it is important to meet the daily recommended intake of vitamin C, this does not mean that taking additional vitamin C in pill form can boost the immune system or help fight the common cold.

Scientific sources:
Vitamin C for preventing and treating the common cold, source
What is vitamin C and what does it do?, source
Vitamin C Supplement – A Science-Based Review of Benefits, Dosage, Side Effects, source