There are many brands and types of whitening tablets on the market, whose whitening principle is mainly to promote the skin’s own metabolism of melanin and inhibit the activity of skin tyrosinase, with common ingredients such as vitamin C, vitamin E, vitamin B, L-cysteine, tranexamic acid and plant extracts. Nowadays, there are almost no authoritative studies to prove the effectiveness of the various types of skin whitening tablets. Tranexamic acid is commonly used clinically as a hemostatic drug, and overdose can have the risk of blood clots. And for patients with a history of cerebrovascular disease and thrombotic disease, there may be a risk of life if tranexamic acid-containing whitening tablets are taken freely. Vitamin C is a very common ingredient in all kinds of whitening tablets. Scientific research shows that if you want to rely on vitamin C to achieve whitening, antioxidant and promote collagen synthesis, you need to take at least 1000mg of vitamin C every day, but the maximum intake of vitamin C recommended by the Chinese Nutrition Society is 1000mg/day. If you overdose vitamin C for a long time, it may cause high iron erythrocyte anemia, as well as gastrointestinal discomfort such as diarrhea, abdominal pain, gastrointestinal bleeding, etc. Some people may also cause hyperuricemia and accelerate the formation of kidney stones or bladder stones, etc. Healthy whitening can be done from basic sun protection, and you should try to choose safe and effective whitening methods to avoid side effects.