L-ascorbic acid is the most common, active form of Vitamin C. This water-soluble antioxidant supports immune function, collagen synthesis for skin and joints, and iron absorption from plants.
Many people take L-ascorbic acid for general immunity, skin health, wound healing, and to lower oxidative stress. Some take higher doses when cold symptoms first appear, but the evidence for this is mixed.
You can take it as a tablet, capsule, or powder. Since L-ascorbic acid is acidic, take it with food or a full glass of water to reduce stomach upset. Buffered or time-release versions are easier on the stomach.
High doses, above 2,000 mg a day, can cause diarrhea or stomach upset. If you’ve had kidney stones or take blood thinners, talk to a doctor before using high doses.