Absolutely, you can take vitamin C while breastfeeding! According to the National Institutes of Health1 , not only is it safe, but the recommended daily allowance for vitamin C is even slightly higher for breastfeeding parents.
But remember, everything in moderation. The body has a limit on how much vitamin C it can absorb at a time. A study in the American Journal of Clinical Nutrition found that absorption decreases when intake is around 400 mg a day or higher.
Don't forget that fruits and vegetables are great sources of vitamin C. Oranges, strawberries, bell peppers and many other foods are rich in this essential vitamin.
Of course, even though vitamin C is generally safe, it's still wise to discuss any dietary changes or supplements with your healthcare provider.