Since nearly half of U.S. adults fail to consume minimum requirements of vitamin C daily, it’s unlikely that the average person will overdo it on vitamin C.
So what are those minimum daily requirements? Per the National Academies, the recommended daily intake of vitamin C is 75 milligrams for women (85 and 120 milligrams if pregnant or lactating, respectively) and 90 milligrams for men, or about 1.5 oranges.
However, those baseline starting levels are debated. Michels says a daily minimum of at least 200 milligrams is actually needed to maximize blood concentrations of vitamin C. He recommends 400 milligrams daily, though evidence suggests that even higher doses can help bolster vitamin C status and promote optimal cardiovascular benefits.*
When it comes to safety, those taking higher potency vitamin C supplements shouldn’t worry—up to 2,000 milligrams of vitamin C daily is considered safe. Beyond that, the side effects listed above may begin to occur, but are generally mild and short lived, Michels says.
That’s because vitamin C is water soluble, meaning it’s transported through the bloodstream and doesn’t need another mechanism to move around, like a fat-soluble vitamin does. Thanks to vitamin C’s water solubility, “the body can easily remove any excess through the kidneys,” Michels explains.