The importance of vitamin C, also known as ascorbic acid, in our diet cannot be overstated. There are many health conditions that will simply run rampant through our bodies without this key component of our immune system. However, vitamin C also plays an important role in the growth of new cells in the body, including those that develop in hair follicles. For those struggling with alopecia areata, a vitamin C-rich diet is essential if they want to slow down or reverse the effects of this condition. Some of the best foods that will help you stock up on vitamin C include strawberries, kelp, pineapples and broccoli.