Vitamin C is one of those micronutrients that your body does not produce on its own. These are called essential vitamins. With proper nutrition, we receive these vitamins and our bodies use them for different functions. For example, Vitamin C is used to treat and prevent scurvy and shorten the common cold. When it comes to your skin, you can't just eat a bunch of oranges and hope that your hyperpigmentation will go away. However, with a topical Vitamin C solution, you can lighten and even get rid of your freckles and sun damage. So how does it work? Basically it blocks an action called tyrosinase, which turns tyrosine into melanin (the thing that gives your skin color).
When your body is producing too much melanin, you can form dark spots. The sun is the biggest culprit in producing high amounts of melanin. It's how your skin tans or burns and is your skins way of protecting you from the harmful UV rays. This is why it is so important that you wear sun protection all day, everyday even if you are only walking from your car to the office. You can visibly lighten your hyperpigmentation with a product that contains Vitamin C and by eating your vitamin C. Be careful not to over-do it with an oral supplement as too much can cause negative side effects. The daily recommended amount of Vitamin C that you should take is 65mg for females over the age of 18 and 75mg for males over the age of 18.