VC is vitamin C. The structure of vitamin C is similar to glucose, and it is a polyhydroxy compound. Two adjacent enol hydroxyl groups at the second and third positions in its molecule are easily dissociated to release H+, so it has the property of acid, also known as ascorbic acid.

vitamin c has strong reducibility and is easily oxidized to dehydrovitamin c, but its reaction is reversible, and ascorbic acid and dehydroascorbic acid have the same physiological function. However, if dehydroascorbic acid continues to be oxidized to generate diketonate, the reaction will be irreversible and lose its physiological efficacy completely.

vitamin c is necessary for the formation of antibodies and collagen, tissue repair (including some redox actions), metabolism of phenylalanine, tyrosine and folic acid, utilization of iron and carbohydrates, synthesis of fat and protein, maintenance of immune function, hydroxylation of 5- hydroxytryptamine, maintenance of blood vessel integrity and promotion of non-heme iron absorption.

At the same time, vitamin C also has the functions of antioxidation, anti-free radical and inhibition of tyrosinase formation, thus achieving the effects of whitening and lightening spots.

Extended information:

Symptoms of insufficient p>VC intake:

1. General symptoms

The onset is slow, and vitamin C deficiency takes about 3 ~ 4 months before symptoms appear. There are no specific symptoms in the early stage, and patients often have pale face, fatigue, loss of appetite, depression and other manifestations. Children are irritable and do not gain weight, which may be accompanied by low fever, vomiting and diarrhea.

2. Hemorrhage symptoms

Skin petechiae is its prominent manifestation. When the patient's skin is slightly squeezed, it may appear scattered bleeding spots, and the skin is prone to purpura and ecchymosis after being hit or pressed. With the progress of the disease, the patient may have keratinization and bleeding around the hair follicle, and the hair roots are curly and brittle. The gums often swell and bleed, which is easy to cause secondary infection, and the teeth may loosen and fall off due to alveolar necrosis.

There may also be nosebleeds and orbital subperiosteal bleeding, which may cause exophthalmos. Occasionally, gastrointestinal bleeding, hematuria, intra-articular bleeding and even intracranial bleeding are seen. The patient may suddenly have convulsions, shock and even death.

3. Anemia

Due to long-term bleeding, in addition, vitamin C deficiency can affect the absorption of iron, and patients are often accompanied by anemia and pale in the late stage. Anemia is often moderate, usually cellular anemia with normal hemoglobin, and in a series of cases, 1/5 patients may be megaloblastic anemia.

4. Skeletal symptoms

Subperiosteal hemorrhage or metaphyseal dislocation of long bone can cause pain in the affected limb, leading to pseudoparalysis. One of the early symptoms of infants is that their limbs are in a frog position, and any movement of their limbs will make them cry, mainly because the joint capsule is full of bloody exudates, so their limbs can only be in a flexion state but not straight.

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