According to the 2012 edition of the Dietary Guidelines for Chinese Residents, the recommended daily intake of vitamin C for Chinese residents is 100mg, which is, of course, the amount for the whole country.
If you live in the city, you are surrounded by electronic products, automobile exhaust, air pollution, work pressure and so on "negative nutrients" too much, vitamin C intake should be increased to about 500mg ~ 800mg. It is worth noting here that the maximum daily intake of vitamin C is 1000mg, if this amount is exceeded, the human body may appear such as diarrhea and other discomforts.
Because vitamin C is a water-soluble vitamin, intake within the maximum intake of 1,000mg is generally not harmful to the body, and can be quickly excreted through the urine.
Expanded Information:
Supplementation of vitamin C precautions
1, and pig liver at the same time, failure
Vitamin C is easily oxidized inactivation, especially copper, iron ions, which will accelerate the rate of oxidation by thousands of times. And pig liver is rich in copper, iron ions, therefore, vitamin C and pig liver at the same time, will make vitamin C generate other substances, and failure.
2, not with eggs
Milk and other vitamin B2 rich in food at the same time. Vitamin B2 has redox properties, and its oxidation is stronger than the reduction. Both at the same time, not only will make the vitamin C failure, but also affect the role of vitamin B2 in the body to play, can be said to be a "lose-lose".
3, take vitamin C at the same time do not eat a lot of cucumbers, carrots and other vegetables
Because these vegetables contain vitamin C decomposition enzyme, this enzyme can promote the decomposition of vitamin C, and then can not play a role.
4, smoking less vitamin C
While in the smoker's body vitamin C content is lower than that of non-smokers, they need to be supplemented, but studies have shown that smoking will make the saliva of the vitamin C to change the nature of the body into a harmful substance.
People.com - Who needs to take vitamin C supplements?The dos and don'ts of vitamin C supplementation