VC is a highly effective antioxidant in human body, which has antioxidant and anti-free radical effects, and can inhibit the formation of tyrosinase. Tyrosinase is the key enzyme to promote melanin metabolism. Simply put, there are more tyrosinase, and the activity of melanin is high, and the number will increase, leading to blackening of the skin. After inhibiting tyrosinase with VC, melanin metabolism slows down and the skin becomes whiter. This is the key evidence that VC can whiten skin.
In addition to whitening, VC can also enhance the stress and immunity of the body and promote the production of collagen in the skin, thus making the skin healthier and younger.
The structure of vitamin C is similar to that of glucose, and it is a polyhydroxy compound. The second and third adjacent enol hydroxyl groups in its molecule are easy to dissociate and release H+, so it has the nature of acid, also known as ascorbic acid. Vitamin C has strong reducibility and is easily oxidized to dehydrovitamin C, but its reaction is reversible. Ascorbic acid and dehydroascorbic acid have the same physiological function. However, if dehydroascorbic acid continues to oxidize to diketones, the reaction will be irreversible and lose its physiological function completely.
taboo
● Vitamin C should be taken on an empty stomach, but it should be used with caution in patients with digestive tract ulcer, so as not to stimulate the ulcer surface and lead to ulcer deterioration, bleeding or perforation.
● People with poor renal function should not take more vitamin C. Long-term overdose of vitamin C may cause hyperacidity, gastric reflux and even urinary calculi. Especially people with kidney deficiency should eat less vitamin C.
● Don't suddenly stop taking vitamin C after taking a large amount. If the sudden withdrawal of vitamin C will cause withdrawal reaction, which will aggravate or recur the symptoms, it should be gradually reduced until the withdrawal is complete.
● Vitamin C should not be combined with isoniazid, aminophylline, streptomycin, penicillin and sulfonamides; Otherwise, the efficacy of the above drugs will be reduced or ineffective due to acidic environment.
● Vitamin C has a destructive effect on vitamin A, especially after taking a large amount of vitamin C, it will promote the excretion of vitamin A and folic acid in the body. Therefore, while taking a large amount of vitamin C, we must pay attention to the sufficient amount of vitamin A and folic acid.
● Vitamin C combined with aspirin enteric-coated tablets will accelerate its excretion and reduce the curative effect.
● Don't take ginseng when taking vitamin C. ..
● The combination of vitamin C and folic acid will also weaken their respective effects. If you need to treat anemia, you can use it intermittently and not at the same time.
● taking medicine indiscriminately will lose vitamin c in the body. If you take medicine without the doctor's permission, it will not only damage your health, but also cause the loss of vitamin C in your body.
● Vitamin C tablets should be stored in a cool and dark place to prevent deterioration and failure.
● Vitamin C cannot be taken in large quantities with crustacean seafood such as shrimps and crabs, which will produce arsenic trioxide (arsenic) and even poisoning. (This article is an online rumor, and its "mass" means that you need to consume about 50 kilograms of fruit rich in vitamin C and 200 kilograms of seafood at the same time within 24 hours. )
● Take vitamin C and avoid eating animal liver. Vitamin c is easily oxidized. If copper ions are encountered, the oxidation speed can be accelerated. The copper content in animal liver is very high. If you eat animal liver during taking vitamin C, vitamin C will rapidly oxidize and lose its biological function.
References:
Baidu encyclopedia entry VC