Medically reviewed by Mary Choy, PharmD Key Takeaways High doses of vitamin C, especially above the tolerable upper limit of 2,000 mg per day, can lead to serious side effects such as kidney stones, ...

Vitamin C plays a crucial role in the function of immune cells. Individuals with infections tend to have lower levels of vitamin C. However, research has not found conclusive evidence that taking ...

Now that flu season is here, a lot of people are stocking up on vitamin C in hopes of warding off a cold. At the first sign of a sniffle, they start downing mega-doses of the vitamin. Is this really ...

As cold and flu season ramps up and holiday travel begins, many people reach for vitamin C supplements to help prevent getting sick on the road.

A prolonged vitamin C deficiency can cause severe and potentially life threatening symptoms. Eating a variety of fruits and vegetables can help maintain optimal levels of this important nutrient.